2196
Fourier transform infrared spectroscopy combined with Partial least squares (PLS) regression
Can be used to predict the presence of beef in pork meatballs.
Control points - Defined by regulation when product *identity* is of concern. Critical control points - Defined by regulation when *public health* is of concern.
Critical control points vs control points - defined by:
chemical, physical and microbiological
Critical, major and minor attributes are usually from key _________, ________ and __________properties.
1) Determine the critical descriptors - those that change the most during storage. 2) Produce samples with increasing levels of the sensory defect (using sampling design) 3) Use a trained panel to determine intensity levels of descriptors 4) Determine acceptability of samples with a consumer panel 5) Calculate the COP (calculate level of significant reduction of acceptability, then plot acceptability against the critical factor tested 6) Conduct sensory for samples at different storage times 7) Use COP to predict shelf-life
Cut off point method steps (7)
Popular in daily QC. For where there is inherent variability - baked and snack products.
DFC (Difference From Control)method uses:
Shipping
Final step where the organisation can have any direct control on product quality.
Appearance (colour) Flavour (and odour) Texture Size Freedom from defects
Five quality parameters associated with sensory factors:
engage improvements ownership
Key is to _______ production personnel in addition to quality control personnel. Consider ___________ suggested by employees. Key is to ensure employees follow the instructions - sense of __________.
Time Temperature Equipment needed Order of addition Weight
Key points for processing operations: (5)
*control points.* (These are where if something changes there is a consequence.)
In-process measurements usually based on:
1) Reference Number 2)Cause & Effect (Fishbone) chart. 3)Action 4)Champion 5)Target Date 6)Effectiveness 7)Current Status
Included in a corrective action matrix: (7)
Transitions between vibrational energy states: stretching Bending
Infrared analysis depends on:
1) Name of Ingredient 2) Internal Code Number 3) Effective Date 4) Basic Description of Ingredient Specifications categorized as: Critical Major Minor 5) Action and Reject Levels 6) Ingredient Statement
Ingredient specifications should include: (6)
A consumer rejects samples between two sampling points other than the first and last sampling point
Interval-censoring:
Water activity (aw) (avail. H2O). Natural microflora & surviving microbiological counts. pH value - total acidity; acid type Available oxygen. Redox potential (Eh). Nutrients. Natural biochemistry of the product formulation (enzymes, chemical reactants). Use of preservatives (e.g. salt)
Intrinsic factors to be considered that will alter shelf-life: (8)
*censoring*
It is often not possible to systematically observe the failure time for all samples - this is called __________ (estimates of lifetimes that are known to have occurred only within certain intervals)
Name of the product. Internal code number. Effective date. Listing of the ingredients. Listing of the ingredient code. Percentage formula. Batch formula. Batch yield. Ingredient statement.
Key aspects of any formula document (Product Formulation/Recipe Specification) are: (9)
1) External Failure cost > Lost sales, customer complaints, returns and warranty costs 2) Internal Failure cost > Scrap cost, rework, downtime, downgrading
TQM - What is involved in conformance costs? (2)
The standard for quality should be "defect free"
TQM - standard for quality should be:
*Proactive* - identify problems before they happen. Make *continuous improvements* on Quality. Properly *manage quality*. *Plan and organise* quality improvements. Goals should be based on *requirements*
TQM should: (5)
*Spoilage organisms*: storage of the product at different temperatures and determining spoilage by sensory evaluation or microbial count. *Pathogens*: challenge testing - inoculate the product with the 'risk' organism prior to processing, storage and distribution and microbial analysis at intervals. To see what happens to the organism.
Testing for pathogens vs Testing for spoilage organisms
Procedures for recruitment and selection The degree of training required by the assessors The type of assessors and the number of assessors
The *type* of sensory test selected affects: (3)
Quality Function Deployment (QFD)
The 4 stages of quality planning form part of a quality framework known as:
Say what you do - clearly and accurately Do what you say Prove it Improve it
The Motto of ISO Continuous Improvement: (4)
functional groups
The __________ ________ present in a molecule can be deduced from an IR spectrum
*If* there is a possibility that a given policy or action might cause harm to the consumer, *and* there is still no scientific consensus on the issue, *then* the policy or action should not be pursued.
The precautionary principle states that:
Stratified defect check sheets. These check sheets stratify a particular defect type according to logical criteria. Helpful to identify root cause/s of a problem.
The following is an example of?
Survival Curve a curve of probability of survival with time. Can be done for survival or rejection
The following is an example of?
This is a normal distribution, but there is data outside of specification - so not capable of meeting specification - adjust process
The following is an example of?
Triangle Test Ballot
The following is an example of?
ballot sheets for semi-quantitative descriptive testing for specifications
The following is an example of?
Showing a Weibull model - use best fit model from different statistical models for the best parametric survival curve.
The following is an example?
control limits
The intensity measures from the panels can be used in a SPC with sensory specification as _________ _________
normally distributed or if it is skewed
The shape of the histogram is studied to identify if data is:
False - these controls do help
True or False SPC cannot be deployed in the food industry because of the number of variables for food quality control
True
True or False SPC is already being used in the food industry
False
True or False SPC is only a reactive system of quality control allowing the organisation to comply with food regulation
True
True or False SPC is a system to identify excessive variation in a process and to help optimise the process
False
True or false The errors in measurement systems used in SPC are of little importance.
GMPs are regulations defining procedures to minimise contamination of food by people in manufacturing, processing packaging and storage.
What are GMPs?
Histograms used to graphically summarise and display the distribution of a process dataset.
What are Histograms used for?
Cause-and-Effect Diagram (Cause Enumeration)
What is defined by the following? All possible causes of a given problem grouped according to rational categories
*Critical attributes*
What is defined by the following? Failure to meet regulation, policies or standards of identity is illegal. Government-controlled attributes of food are an important measure of food quality. A category of food quality including factors that affect safety, wholesomeness or legality.
•Chart Type •Chart Champion - Person(s) responsible to collect and chart the data •Chart Location •Measurement Method •Measurement System Analysis (Acceptable Error?) •Reaction Plan •Gauge Number - Tied in with calibration program •Sampling Plan •Process Stability Status •Cp & Cpk
A control plan should be maintained that contains all information on each process control chart. Include: (10) HOWEVER A CONTROL PLAN CAN BE MODIFIED TO FIT LOCAL NEEDS
A *control point* is a step in process or formulation where small changes can cause the finished product to be illegal or rejected by the consumer. A *critical control point* is a step in process or formulation where small changes can cause the finished product to be a health hazard.
A control point is: A critical control point is:
Proactive Reactive
2 Main Categories of reasons to use SPC in the food industry
1%
% of consumers that correctly answered that date labels are regulated only for specific foods
Useful where a small number of different products are made - so panellists are familiar with 'A'. Used where two samples are not identical in appearance - but differences only noticeable if the two are presented together. Only used if differences are very small (or would have mass rejection)
'A' not 'A' method is useful when:
1) Identifying the customers and their needs 2) Designing the product based on customer needs 3) Design the processes needed to produce the product requirements 4) Implement controls that ensures product are manufactured in conformance to product and process requirements
(4) Stages of Quality Planning
1) Storing product at the appropriate temperature 2) Measuring the microbial load at selected stage intervals 3) *Storage life is 70% of the time to spoilage*
*"Time to spoilage"* is determined by (3)
*Pareto Diagram* *Cause & Effect Diagram* *Flowcharts* *Control Charts* *Histograms* *Scatter Diagrams* *Check Sheets*
*7 Quality Control Tools*
Review control procedures and standards
*Act* stage of PDCA: (1)
Monitor control procedures
*Check* stage of PDCA: (1)
Implement effective control measures Minimise the risks
*Do* stage of PDCA: (2)
*Use of process step charts Use of Cause-and-Effect (fish-bone) diagrams Use of scatter plots (linear regression)*
*If an out-of-control condition is noted, the next step is to collect and analyse data to identify the root cause:* (3)
Identify process steps critical to your standard Identify the hazards
*Plan* stage of PDCA: (2)
*Flow Charts Cause-Effect Diagrams Check Sheets Histogram Pareto Chart Scatter Plot Control Chart*
*The 7 Quality Control Tools used in TQM*
detection prevention
*The SPC process is implemented to move a company from ___________ based to _________ based.*
*Quality planning* 1) Pursue new strategic thinking 2) Know your customer 3) Set true customer requirements *Quality Assurance and control* 4) Concentrate on prevention, not correction 5) Reduce chronic waste *Quality Improvement* 6) Pursue a continuous improvement strategy 7) Use structured methodology for process improvement 8) Reduce variation 9) Use a balanced approach 10) Apply to all functions
10 Steps to TQM:
*Quantitative* measures for sensory can be costly. *Qualitative* testing using taste panels as alternative
2 main categories of sensory testing:
Two presentation orders: A then B B then A Designed so both orders are presented an equal number of times. Both samples presented together and panellist identifies which is higher in the chosen attribute.
2-AFC Method presentation:
Discriminative tests Descriptive tests Preference and acceptability tests
3 Types of sensory assessment
1) In-house laboratories 2) Outside independent laboratory 3) Combined use of in-house and independent laboratories.
3 main types of lab analysis
1) Customer requirement 2) Technical requirements 3) Product requirement 4) Process requirement
4 Phase Quality Function Deployment QFD Model Requirements:
1) An effective simple *product coding system* (date of manufacture, date code plus shiftcode, lot code) 2) *Record keeping system* to identify specific product, product code, carrier and destination. 3) *Recall management team* and the primary contact - 'recall coordinator' 4) *A communication system* (within organisation, with distribution and legal counsel - and to minimise rumour and exaggeration) 5) Established procedures for evaluating and correcting situations.
A recall plan should include: (5)
Used when the actual storage period is long It evaluates product stability at a significantly shorter period than the actual shelf-life Is used when deterioration processes can be modelled by a kinetic model (e.g. Arrhenius model for time to fail with temperature) Factor/s are chosen that can increase the rate of reaction
Accelerated shelf life testing: (4)
In very *simple systems* and where the *mechanisms* involved in the acceleration test are *well known*.
Accelerated shelf-life tests should only be carried out:
by changing temperatures, humidity, pH by reducing the amount of salt or other food
Accelerated storage can occur more rapidly by: (2)
packaging, lot size, regulatory constraints, net weight, package count per batch, etc.
Additional information for any formula document (Product Formulation/Recipe Specification) can be: (5)
Long supply chains to enable cheapest possible purchase leads to greater difficulty in controlling
Advantage of long supply chains (1) Disadvantage of long supply chains (1)
1) Allows organisations to realise what level/s of performance is possible and to set goals. 2) Allows organisations to understand their strengths and weaknesses. 3) Allows documenting reasons as to why differences exist. 4) Helps organisations improve their competitive advantage. 5) Is a cost effective and time efficient way to establish a pool of innovative ideas
Advantages of Benchmarking: (5)
Design actions to eliminate special causes or out-of-control processes. Implement actions to improve process stability. Use tools to organise and track actions (On control charts, Gantt chart, Corrective action matrix) Must identify actions and persons responsible and target dates and completion
After identification of a root cause: (4)
Use pareto chart to identify next highest priority
After successfully reducing process variability , how would the next process be identified?
Maximise productivity while minimising cost. The goal is customer satisfaction.
Aim of TQM (Total Quality Management)
USL - LSL/6 σest
Calculation for Cp
Minimum of x - LSL/ 3σest x - USL / 3σest
Calculation for Cpk
PDCA Plan/ Do/ Check/ Act
Also known as 'The Virtuous Circle'
End Of Shelf Life Parameters Sensory Chemical Functional Microbiological Physical
An acceptable shelf life allows the following desired characteristics of the product to be retained - the ESOLs - what is meant by this and what are the parameters?
fit for purpose
An individual food product specification is used to ensure your product is:
Analysis of variability - Often the focus is on average values. Understanding dispersion is critical for understanding processes.
Analysis of averages must always be accompanied by
1) Ingredient Name and Internal Code . 2) Supplier Name, Address, Key Contact and Phone Number. 3) Trade Name of Ingredient. 4) Supplier Code Number.
Approved supplier list must include: (4)
Literature study Distribution Turnover time Distribution Abuse Test: End point study: Accelerated shelf life testing:
Basic Approaches to Shelf-life Determination (5)
To facilitate trade Also for the purposes of *brand protective competitive advantage*
Brand specific standards normally exist for what purpose? (2)
*Variable data* e.g.: temperature, time, distance, weight (good quality information) *Attribute data* discrete distinctions such as good/bad, pass/fail, number defective per hundred (sometimes relies on arbitrary distinctions)
Categories of data which may be collected for SPC? (2)
1)A box drawn on the far right-hand side display 2)A horizontal arrow pointing to the box. 3)The description of the problem you are trying to solve written inside the box 4)Names of the categories above and below the horizontal line with arrows point towards the horizontal arrow 5)Detailed causes are connected to each category
Cause and effect diagram consists of: (5)
Fishbone Diagram
Cause and effect diagram is also known as
Milk as example: skimmed <0.5% fat whole is at least 3.25% fat
Certain foods or food products are defined by regulations or policies called standards of identity. Such as:
*Lists* of items and some *indicator* of how often each item on the list occurs.
Check Sheet consists of : (2)
Confirmation check sheets.
Check sheets direct the attention of the data collector to items of importance. Simple check sheets are known as:
Quantitative evaluation of nutritive values Quantitative evaluation of composition related to product quality (e.g. moisture content)
Chemical methods can evaluate: (2)
1) Exterior facility and grounds. 2) Internal facility including floors, walls, ceilings and ventilation system. 3) Equipment and all food contact areas.
Cleaning and sanitation programme Three basic areas to address:
All processes exhibit intrinsic variation - *common cause*. Sometimes processes exhibit excessive variation - *special cause* that produces undesirable or unpredictable results.
Common cause vs Special cause
1) foods are heterogeneous 2) chemical reactions involved in food deterioration have complex kinetics 3) composition of the food continues to change during storage 4) food deterioration likely to result from a range of simultaneous processes
Conducting an accelerated shelf-life test that is reliable and accurate is not easy because: (4)
3σ ± mean.
Considering that not all distributions are normal, control limits are set at:
1) Determine the classifications (Pareto categories) for the graph. If the desired information does not exist, obtain it by designing check sheets and log sheets. 2) Select a time interval for analysis. The interval should be long enough to be representative of typical performance. 3) Determine the total occurrences (i.e., cost, defect counts, etc.) for each category. 4) Compute the percentage for each category by dividing the category total by the grand total and multiplying by 100.
Constructing a Pareto Graph (4)
Collect pairs of data with suspected relationship. A plot of one variable versus another. Independent variable is usually shown on the horizontal (bottom) axis. Dependent variable is shown on the vertical (side) axis Not always obvious which variable is dependent and which is independent
Constructing a scatter diagram: (5)
Data plotted in sequence that are taken from samples drawn from a process. Two horizontal lines known as "control limits" are drawn that describe the inherent variability of the process when it is stable (tolerance).
Control Chart consist of: (2)
1) Sampling plan to collect data (subgroups) 2) Random and a determined frequency 3) Rational for variation to be between samples and not those taking samples (i.e. different shifts) 4) Select type of control chart needed
Control charts - After deciding what is being measured and measurement system to be used: (4)
0.3% So outside this limit indicates a process has shifted or become unstable.
Control limits - For normal distribution __% chance of finding a value outside 3σ ± mean
99.7%
Control limits - For normal distribution __% of the population would lie in the curve
Compliance cost Conformance cost Life cycle cost
Cost of Quality - 3 main categories
*The process potential*/The process range
Cp is?
Variability of process AND where is it centered. Consider Cpk as a Cp calculation that is handicapped by considering only half the distribution that is closest to the specification.
Cpk is?
Depends on set criteria for a judgement These being the parameters and criteria of the purchaser - the consumer.
Definition of quality depends on
Consumer perception of quality (consumer panel) Objective quality measurement of sensory attributes (trained panel)
Different sensory methods can evaluate: (2)
1) *Conformance to set standards and specifications*: - does production ever go out of specification or not meet the standards, with what frequency, actions taken to meet standards. 2) *Performance*: - do primary operating characteristics meet specifications 3) *Reliability*: - will the product fail within a certain time 4) *Performance*: - do primary operating characteristics meet specifications 5) *Durability*: - stability on storage - shelf life 6) *Serviceability*: - how quickly can a product be repaired or the competence of the supplied service 7) *Features*: - those features of the product that enhance the product's appeal. 8) *Aesthetics*: - are individual personal preferences met 9) *Perceived Quality*: - indirect subjective measure of quality. not based on the actual product itself, but for example on the reputation of a company and its products.
Dimensions of quality (9)
Some panellist training to understand the attribute - and to judge the difference. If the difference in one attribute affects several others (sugar level in biscuits affects sweetness and hardness) then not a good choice of test.
Disadvantages of 2-AFC (2)
Need for a "control" product ("control" cannot be stored for long) Need to select new product that is representative each time - use of specification to choose a "control".
Disadvantages of DFC (Difference From Control) method (2)
subjective - judgement. Especially if one panellist No information why "out"
Disadvantages of the In/ out (pass/fail) method: (2)
partial pattern
Electronic nose - The sensors have _______ specificity and an appropriate _______ recognition system.
*Sampling system* (headspace) *Sensor array* (chemosensors, semi conducting, catalytic field-effect, acoustic, optical and colourimetric sensors) *Data acquisition system* (including signal processing) *Pattern recognition algorithm*
Electronic nose is comprised of (4)
A *pre-determined level of microbial count* (total count and level of individual microbes)
End-point determined as the time to reach:
*Bug detection in food stores* Infestations usually detected by visual inspection, which is time-intensive and slow. If the bugs live inside the grains, then no visual observation possible. We can listen for the signature noises from the bugs. *Crispy foods* Crispy foods are brittle and noisy
Example uses for ultrasound - methods based on listening (2)
Determining solid fat content in emulsions (melting curve and spreadability). Phase transitions in oil-water emulsions. Solid Liquid Phase Separation. Emulsion behaviour. Enzyme activity (e.g. starch degradation by amylases) Monitoring of composition: sugar content in fruit juices; Hardness/softness of materials: fruit ripeness; food quality Chemical structure of fats: sensitivity to hydrocarbon bond length and degree of bond saturation in fats Solid fat content: melting properties of chocolate Size measurement: measurement of droplet size in emulsions such as salad cream, milk and margarine
Examples for uses of Ultrasound - methods based on low amplitude sound
Product quality. Quality management procedure. Customer services. Manufacture processes. Marketing. Organisation image. Costs. Product development
Examples of aspects that can be Benchmarked (8)
moisture fat protein ash fibre CHO Salt/Na
Examples of chemical characteristics in a product specification (7)
Ingredient Specifications Approved Supplier List Product Formulas Product Standards (Specifications) Manufacturing Procedures (Specifications) Critical Control Point Identification/Sampling Program In-Process Analysis, Records and Reporting Packaging Specifications Label Specifications Cleaning and Sanitizing Program Good Manufacturing Practices (GMP) Requirements Recall Program Warehousing, Shipping and Receiving Program Laboratory Analysis
Examples of key elements for QC (14)
size shape dimensions weight volume count per package
Examples of physical characteristics in a product specification (6)
enzyme reaction rates, enzyme concentration, moisture content, solid concentration, pH
Examples of quick/ rapid methods that can be used on the manufacturing floor during processing: (5)
Weight, pH, temperature, moisture, salt.
Examples of simple physical measurements, on- or at-line include: (5)
product weight temperature size and shape ingredient usage product yield scrap or waste material balance rework
Examples which may be recorded by in process records: (8)
visual tests
Except from ________ ______, all laboratory analysis must be carried out in a room away from the processing area.
1) Time-temperature profile or control during processing, storage and distribution; 2) Relative humidity (RH) during processing, storage and distribution. 3) Exposure to light (UV and IR) during processing, storage and distribution 4) Environmental microbial counts during processing, storage and distribution. 5) Composition of atmosphere within packaging. 6) Subsequent heat treatment (e.g. reheating or cooking before consumption). 7) Consumer handling.
Extrinsic factors affecting shelf-life (7) (Factors the final product can encounter as it passes through the food chain)
1) *Raw materials/Ingredients* used to make the food - specification of the raw materials. 2) *Substance/s that comes into direct contact* with the food at any stage of production. 3) *Design of the production process* and equipment used. 4) *Process conditions* meeting process specifications 5) *Packaging, storage and distribution* systems
Factors affecting food quality (5)
TIme Microorganisms Enzymes Insects/ rodents Chemical reactions Environmental factors
Factors affecting food spoilage (6)
raw material type, quality, product formulation food structure
Factors affecting shelf-life: (4)
*Food Quality* is "the extent to which all the established requirements relating to the characteristics are met. *Food Safety* is "the assurance that food will not cause harm to the consumer when prepared and eaten according to its intended use".
Food Quality Assurance includes *both* Food Quality and Food Safety. Define Food Quality: Define Food Safety:
Protects the product during transport Impression of food quality
Food packaging is used for: (2)
Food quality = conformance to standard (i.e. the specification) High quality = high conformance Low quality = low conformance Quality being "... of the nature, substance and quality demanded by the consumer ..."
Food quality = High quality = Low quality =
Used daily to ensure consistency between batches.
For each food product need written information of formula/recipe. What is this used for?
2.0 double
For many products Q10 is __, so every rise of 10C causes the reaction to ________
Standard plate count
General indicator for bacterial quality:
• Choose your team • Call the kick-of meeting • Define areas for improvement • Follow the simplified process in the flowchart • Choose and apply the basic analytical tools • Analyze and report the results • Make the modifications required for improvement
Getting started in TQM (7)
Hazard = Danger Risk = Probability
Hazard = Risk =
Vitamin and mineral content, nutritional content, oxidation of fats/oils, separation characteristics, rancidity.
How are Chemical methods used in shelf-life?
culture media (selective to identify) and grown for counts, Immunoassay, PCR.
How are Microbiological methods used in shelf life?
Texture analysis, pH, water activity, moisture content.
How are Physio-chemical methods used in shelf-life?
appearance, odour, taste, texture. Often assessed by 8-10 experienced panellists (but designs also for customer requirements). Shelf life study typically ends when a product is unacceptable to panellists.
How are Sensory methods used to test for shelf life?
1) Developing a flow chart of the area to be improved 2) Defining the problem to be solved 3) Conducting a Brainstorming session to find all possible causes of the problem 4) The diagram organises the brainstorming results into rational categories
How are cause and effect diagrams constructed? (4)
Defined by *regulation* when product *identity* is of concern. Control points are *self-imposed* because of desired label statements to ensure that specification is met
How are control points defined? (3 key words)
Defined by *regulation* when *public health* is of concern.
How are critical control points defined? (2 key words)
1) Segment the range of the data into equal-sized bins (i.e., segments, groups, classes) 2) The vertical axis of the histogram is the frequency (i.e., the number of counts for each bin) 3) The horizontal axis is labelled with a range of the response variable 4) The number of data points in each bin is determined and the histogram constructed
How are histograms constructed? (4)
Quality control and production personnel maintain a daily manufacturing log.
How are in process records kept?
Using *descriptive techniques* and *trained and screened panels* a sensory specification is produced - the standard against which the product is tested for QC.
How are sensory targets defined for sensory specifications?
By ensuring that process parameters are within specifications so that final product characteristics are met
How is waste minimised in QC?
There are *seven quality control tools* and *eight management and planning tools* that can be used for problem-solving and process improvements in TQM
How many quality control tools & how many management and planning tools are used in TQM ?
yield quality production efficiency
Identify key process steps that impact on: (3) (Manufacturing Procedures - Specifications)
1) Bimodal distribution 2) Unitary distribution 3) Negatively skewed 4) Positively skewed
Identify the types of distribution
Benchmarking
If you are the industrial leader with multiple sites, ____________ is against the best production in the company.
Planning Commitment across several functional boundaries. Construct a flow chart
Implementation of SPC requires: (3)
Visually depicts which situations are more significant
In Pareto Analysis The lengths of the bars represent frequency or cost (time or money), and are arranged with longest bars on the left and the shortest to the right. Why is this useful?
Plan
In Process Records are a part of which stage of PDCA?
What is happening during manufacture.
In Process Records obtain information about:
spider plot
In QC If asked to compare two products: Use of a descriptive test can lead to SPC or plotting graphs such as a _______ ______ which allows answers to which has more lemon odour / most sour
Right-censoring: At end of the study: A consumer still accepts the sample stored for the maximum time In the middle of the study: a consumer no longer wants to taste samples stored for successive times even though the product is still acceptable
In Right Censoring At the end of the study: In the middle of the study:
Quality planning Quality improvement Quality control
In all quality management systems there are (3) key elements:
Doing analysis Reporting results Managing the QC Record test results and compare to specifications or standards Communicate deviations from standards for additional actions to be considered and planned
In lab analysis, qualified staff are required for which processes? (5)
sound speed
In mixtures, measurement of the _______ _______ can tell us the concentrations.
Conformity of raw materials, intermediate and final products Batch to batch consistency Detection of contamination, spoilage, adulteration Origin or vendor selection Monitoring of storage conditions
In quality control laboratories, electronic nose can be used for (ĕxamples):
1) Outline specific activities to be performed 2) Any corrective measures 3) Schedules for cleaning and sanitizing 4) Identify approved cleaning compounds, sanitizers and baits and define a standard. 5) Keep and maintain proper records.
In the cleaning and sanitation programme, the quality program should: (5)
LECTURE 4 - TQM
LECTURE 4 - TQM
LECTURE 5 SPC
LECTURE 5 SPC
LECTURE 6A
LECTURE 6 A
LECTURE 6B
LECTURE 6B
LECTURE 7A SHELF LIFE
LECTURE 7A SHELF LIFE
specialised facilities and expertise.
Lab analysis can vary from simple comparison to colour charts to specialised instrumental analysis. Microbiological analysis is ____________ and needs _________ and _________
specifications
Laboratory analysis or an evaluation programme is essential to establishing _______________.
Only the time of the event is known - start is not at end of production - this time is unknown
Left-censoring:
Ensure that foods are fit for human consumption and protect consumers from harm resulting from unsafe foods. To protect consumers from deception resulting from misrepresentation or fraud. Also establishment of specific processing conditions so that foods are not contaminated.
Legal standards are mandatory and set up through law. They are designed to: (3)
Moisture loss Moisture uptake Chemical reactions Microbial growth Enzyme action Oxidation
Main deterioration mechanisms in foods: (6)
Simple way via 'cookbook' approach.
Manufacturing Procedures - Specifications approach
Include special instructions to *line worker*. Include special instructions to *quality control personnel*. Once a manufacturing procedure is prepared provide to *production personnel*. (Document can be used as a training tool.)
Manufacturing Procedures - Specifications should include instructions for: (3)
using colour charts Use of reflectance spectroscopy.
Measurement of colour can be carried out
by the standard deviation (σ) - easily calculated
Measurements recorded can be represented in a histogram showing the distribution. Shows the spread of data - can be shown by the lowest value to highest value. How is this better expressed?
Chemical methods
Measuring methods used for legislation and labelling
1) Sensory methods 2) Physical methods 3) Chemical Methods 4) Microbiological Methods 5) Quick or rapid methods
Methods for Measuring Quality (5)
Quantitative evaluation of food poisoning organisms Quantitative evaluation of food spoilage organisms
Microbiological Methods can evaluate: (2)
1. microbial growth, which leads to the spoilage of a food product. 2. the growth of microbial pathogens that affect the safety of the product
Microbiological stability depends on: (2)
product
Microbiological standards are _______ specific
Mid-infrared cannot penetrate far into a sample and sample preparation is required. Near-infrared can penetrate a sample and so can be done with no sample preparation - can probe bulk material
Mid Infrared vs Near Infrared
IR spectroscopy, NIR spectroscopy, Raman spectroscopy. Reflectance spectroscopy. Ultrasound Imaging - multivariate image analysis, laser backscattering. Rapid microbiological methods
More sophisticated on-line measurements using rapid method technologies using sensors: (5)
Safety and wholesomeness
Most important attributes of food quality (2)
Makes replication from day to day easier.
Need to document processing procedures. What use does this have?
100
On average there are over ___ food recalls per year
product name ingredient statement manufacturing or distribution location.
On food packaging, the law requires display of (3)
All check sheets are submitted to supervisory management for review to identify problem areas and to plan and make changes to prevent reoccurrence.
Once process check sheets have been completed:
Line of Best Fit.
One way to show the strength of a correlation in scatter graphs is to use the:
1) Individuals with infectious diseases, wounds, boils cannot work in areas where food can be contaminated. 2) Food handlers must follow good personal hygiene practices 3) Train employees effectively in hygiene, sanitation and pest control
Overview of GMP (3)
1) Composition of packaging and material 2) Dimensions 3) Strength of the container (and suitability for stacking, freezing or microwaving) 4) Strength of seals or fit of the lid. 5) Ability to restrict or allow air flow, moisture or light. Permeability, thickness, flexibility and temperature resistance. 6) Graphics 7) Label format and legal requirements.
Packaging considerations: (7)
Dairy products require UV blocking and non- permeable to oxygen packaging.
Packaging required for dairy products
require packaging that provides *protection* while allowing *air flow* for proper cooling and respiration.
Packaging required for fruit & veg
Difference tests
Paired comparison, duo-trio and triangle test are which type of sensory test ?
*Product attributes* - Size, texture, colour, consistency, and imperfection *Process variables* - Headspace, fill weight, drained weight, vacuum, etc.
Physical quality measurements can evaluate: (2)
analytical or sensory
Prediction of shelf life can be through _________ or ________ methods.
The use of mathematical models to describe microbial responses to the environment.
Predictive microbiology is:
Price is determined by market forces, by supply and demand Price is not the same as cost
Price is determined by: Price vs Cost
1) Customer focussed 2) Total employee involvement 3) *Process* centered 4) Integrated system 5) Strategic & systematic approach 6) Continual improvement 7) Fact based decision making 8) Communications
Primary Elements of TQM:
Formulation + Processing Details determine the process specification
Process Specification Includes (2)
Pathogens Toxins Contaminants Allergens
Product *safety* factors (4)
Sensory + Physical + Microbiological + Chemical + Nutritional profile determine the product specification
Product Specification Includes (5)
Establish *acceptable methodology* for each product standard. Establish a *reject level* for each product standard. Minimum reject levels based on *regulatory requirements AND practical production experience*. If no method of measurement then no standard. Include statement of ingredients.
Product specification must include: For each product standard
physical, chemical and microbiological characteristics. Sensory properties of a food product are keys to the consumer acceptance
Product standards define the food by which characteristics? (3)
Pros: Gives full cost, shows breakdown and helps understanding of factors that increase cost. Cons: Not easy to do or design, time consuming, difficult to estimate operational and maintenance costs
Pros and Cons of Life Cycle Cost
To determine whether the quality and safety requirements are fulfilled by detecting whether unacceptable levels of hazards or defects exist in foods
Purpose of quality control
Q10 = (R2/R1) ^(10/(T2-T1)) R is the time it takes for a product to spoil T is the temperature for the test
Q10 is unitless and can be calculated with the equation:
The factor by which the rate of spoilage increases when the temperature is raised by 10C.
Q10 is:
Quality = conformance with specification Quality management = assuring conformance
Quality = Quality management =
Preventing any quality defects and food safety hazards - to ensure that the food product is fit for purpose.
Quality Assurance is aimed at
QA has QC at its core to control the quality But also considers related activities or processes (such as training, document control and audits).
Quality Control vs Quality Assurance
*Consumer perception* - different criteria/parameters and judgements about what quality is. *Product characteristics* - What features or attributes enhance product quality - the specifications? *Production requirements* - Is our product in conformance to specifications? *Value* - Is the product at an "acceptable price"? - Is the cost to achieve quality at an "acceptable cost" ?
Quality is defined from (4)
*Critical attributes* *Major attributes*: necessary for the food but not essential for safety and legislation (eg fat content in minced meat) *Minor attributes*: wanted for the food, but not essential to the product - or not easily determined
Quality of Foods - 3 Main Attributes (categories)
Gives instructions for out-of-control or out-of-specification condition. Often use of a flow chart (with a reference number - the flow chart must then be referenced on the SPC chart)
Reaction plan in SPC used for?
Sampling plan, and an analysis frequency is required.
Required for lab analysis (2)
Commitment + Awareness + Teamwork + Communication + Quality Control = Safe, Wholesome and Consistent Food Products
Requirements for safe, wholesome food products (5)
control
SPC is means to help optimise and so _______manufacturing processes.
variation
SPC is used to reduce _________ to achieve the best target value.
The strength and direction of the linear relationship between two variables.
Scatter diagrams - The R Value, which is also called Pearson's Correlation Coefficient is a measure of:
Used when you have paired numerical data Used when trying to determine whether the two variables are related
Scatter diagrams are used when: (2)
Few chemical/physical methods are available for fast assessment.
Sensory analysis is required in quality control because:
1) First detectable change or just-noticeable difference: Using difference tests and a suitable reference sample. 2) Measured attribute change: A fixed level of change is considered as a cut-off point. 3) Change in consumer acceptability
Sensory criteria for shelf-life determination (3)
Descriptive specification In/ Óut (ŏr pass/fail) Difference from control In house methods DIY methods Quality scoring/grading/rating
Sensory tests with *high relevance* to QC
Product category, type, nature Risk of spoilage Chemical reactions Physical changes Organoleptic, sensory, consumer Packaging protection/ transport and storage/ consumer Usage
Shelf life factors (*not* safety related) (7)
If suppliers or formulations are changed shelf-life should be confirmed. Even with no change, confirm shelf life several times each year.
Shelf life should be confirmed when: (2)
1) Remain safe. 2) Be certain to retain desired sensory, chemical, physical and microbiological characteristics 3) Comply with any label declaration of nutritional data
Shelf-life is the time, when stored correctly, during which a product will: (3)
1) determine the shelf-life of *existing products*. 2) *study the effect of specific factors and combinations of factors* such as storage temperature, package materials, or food additives on product shelf-life. 3) tests designed to determine the shelf-life of *prototype or newly developed products*.
Shelf-life testing can be divided into three categories:
Cp is in excess of one (>1) However the process is not centred. This means that the process will still fail to consistently meet customer expectations (i.e. product outside of specification) - Hence the need for Cpk
Significance of the value of Cp here?
• *Many deterioration process* - different changes may occur at accelerated conditions. • *Inability to quantify uncertainty* - e.g., using a single accelerated factor. • *Effect of unforeseen variables* - e.g., changes during distribution. • *True critical descriptor incorrectly identified* - reaction rate higher for different factor at accelerated conditions. • *Different deterioration process* - deterioration reactions at accelerated conditions not representative of reactions at actual storage conditions. • *Increasing temperature results in slower deterioration* - enzymatic reactions and microbial activity slows down.
Some problems of ASLT (6)
moving range chart
Specifications are *not* expressed as lines on control charts because the plot point is often an average value, not an individual value. The only exception is the ________ ______ ______, which is based on a subgroup size of one
Specifications are not related to control limits - they are completely separate. (Specifications should be printed on the side, top, or bottom of the chart for comparing individual readings.) *Specifications* - "what the customer wants", *Control limits* - "what the process can deliver".
Specifications vs Control Limits
Food fraud Potential health dangers.
Standards reviewed and changed to prevent: (2)
Different types of check sheets (Manual or automatic)
Statistical Process Control is based on the analysis of data from :
Step 1 - Generate ideas Step 2 - Display ideas Step 3 - Sort ideas into groups Step 4 - Create header cards Step 5 - Draw finished diagram
Steps in creating an affinity diagram (5)
Step 1 - Generate ideas (individually) Step 2 - Display ideas Step 3 - Draw arrows between related ideas (An idea that has arrows leaving it but none entering is a "root idea" or "root cause")
Steps in creating an interrelationship digraph (3)
receiving storage shipping
Storage (warehousing) Three activities in a QC programme:
1) Desirable to have more than one supplier for each ingredient. (at least 3) 2) If ingredient has a manufacturer and a distributer identify both on the supplier list. 3) Evaluate ingredient performance in product - needs to give desired product. 4) Must meet ingredient specification
Suppliers for each ingredient require (4)
A collection of statistical procedures for data analysis for which the outcome variable of interest is *time until an event occurs*. (Failure criterion is judged to be reached)
Survival analysis is:
The length of time after the product has left production until it is deemed unacceptable by the consumer.
Survival is:
All members of an organization participating in improving processes, products, services, and the culture in which they work.
TQM (Total Quality Management) includes which members of an organisation?
Involve customers in the whole product life cycle.
TQM - Customers should be involved at which stage of the product life cycle?
people at all levels.
TQM - Quality is the responsibility of:
1) Prevention costs > Training, quality planning 2) Appraisal costs >Inspection and Testing, operator cost, test equipment cost
TQM - What is involved in compliance costs ? (2)
Targeted Difference from control (TDFC) method ballot
The following is an example of:
The tolerance.
The difference between the upper and lower specification is known as:
Limitations to SPC implementation within the food industry
The following are examples of ? Lack of statistical thinking within food companies Current guidelines 'unable to comprehend' food manufacturing applications Tools considered too advanced for food industry usage 'Too complex' for non-statistical background employees to be applied Food sectors perceived quality improvement initiatives like SPC is costly
Key processes (Manufacturing Procedures - Specifications)
The following are examples of: 'mix for 3 minutes before adding spices' 'cook to a minimum internal temperature of 63C.'
Ballots for 2-AFC and same difference
The following are examples of?
Events that can lead to a food recall
The following are examples of? Illness outbreak linked to a specific food. Food test result identify a possible health risk. FSA inspection activities detect a food safety concern. Consumer complaint about the safety of a food product. Company-initiated Recall in other country Other triggers - can include information from law enforcement about potential food tampering.
Commonly used microbiological lab analysis
The following are examples of? Standard plate count to count the nos. of bacteria in a product. Yeast and mould count to count the number of yeast and mould in food.
Commonly used chemical lab analysis
The following are examples of? pH measurement which determines if a food is acidic, neutral or basic Moisture measurement to determine total water. Protein measurement to determine the protein. Fat measurement to determine total fat.
Typical packaging defects
The following are examples of? smears scuffs colour variations broken seals leaks short fill product infestation spoil age.
Questions on a check sheet posed by the investigator
The following are examples of? "Has everything been done?" "Have all inspections been performed?" "How often does a particular problem occur?"
Reactive reasons to use SPC
The following are examples of? To comply with food regulation and law Customer pressure As diligent defence for prosecution To reduce risk of potential product recall
Proactive reasons to use SPC
The following are examples of? To reduce process variation To increase productivity To gain customer confidence and trust Customer pressure Market competition pressure To reduce cost To improve operational performance To validate effectiveness of QC
Storage (warehousing)
The following are guidelines for? Orderly and correct (temperature, humidity) is essential to quality. Segregation of supplies when appropriate. Rotate inventory.
Guidelines for receiving (Storage (warehousing) )
The following are guidelines for? Storage areas to be clean, date code inventory to ensure rotation of stock. Inspect before unloading - records for refrigerated. Check containers for damage. Collect random samples for analysis to evaluate specification After unloading inspect carrier and note dirt, residues, etc. Do not accept food, ingredients or packaging deliveries combined with chemicals or poisons. Reject all or part of load if specification not met. frozen, chilled directly to storage. date code directly on containers for all incoming for stock rotation.
In-house and DIY methods
The following describes which sensory method Methods for QC - and some have become established (e.g. duo-trio test). Many companies have their own internal gradings based on typicality product quality Often just state good or bad - sometimes informally and entered on check sheets. Although not ideal often have been developed and adjusted over many years: Also have detailed SOP and Work Instructions. Also based on sensory specifications and consumer data. Can give more objective and controlled results.
Duo-trio method
The following describes which sensory method Not ideal for QC as can be sensitive to very small changes. Considered better than triangle test as easier for panellists. Similar to both the triangle and 'A' Not 'A' tests. Reference and 2 samples (3 digit codes) are presented together. Panellists decide which of the 2 samples is the same as the reference.
Magnitude estimation
The following describes which sensory method Very simple but rarely used for daily QC. Exception for specific products such as chilli peppers. Panellists presented with a reference sample and told the score it gives for an attribute. (e.g. chilli heat).
'A' not 'A' method
The following describes which type of sensory test: *Popular in daily QC.* Easy to train panellists. Only states if batch is different Not how they are different. Not how different they are Present 'sample' for familiarisation - a reminder from initial training Then give a series of 3 digit coded samples - some being 'sample' and some not. Random and different order of presentation to each panellist.
Cut off point method
The following is an example of
Difference from control (DFC) method ballot Panellists presented with control and 3 digit coded samples.
The following is an example of:
'A' not 'A' method ballot Panellist number dependent on the test objective - typically 20 needed - each assesses five 'A' and five not 'A' samples. Can tabulate to indicate how many identified samples correctly or analyse using χ2
The following is an example of?
A *Dendrogram* / Tree diagram
The following is an example of?
A GANTT Chart
The following is an example of?
A control plan
The following is an example of?
A corrective action matrix
The following is an example of?
A food process equipment flow chart for potato slice drying
The following is an example of?
A food process steps flow chart for potato slice drying Process steps flow chart- a display the concrete technology, by specifying the conditions of each step.
The following is an example of?
Activity Network Diagram
The following is an example of?
An affinity diagram
The following is an example of?
An interrelationship diagraph
The following is an example of?
Ballot for In/Out method
The following is an example of?
Cause-and-Effect Diagram (Cause Enumeration)
The following is an example of?
Cause-and-Effect Diagram (Production Process) The production processes (i.e., unit operations) is used as the main categories, or branches, of the diagram.
The following is an example of?
Change in Consumer Acceptability Products of different quality levels can have different cut-off point
The following is an example of?
Defect check sheets In these check sheets defects are listed and the observed frequency recorded and can be used to construct a histogram.
The following is an example of?
Defects location Check sheet A visual representation of where defects occur
The following is an example of?
Drawn sample design A single large batch is held under conditions under which quality changes are effectively zero (e.g., frozen storage). Samples are removed at appropriate intervals and stored under the desired conditions.
The following is an example of?
Duo trio method ballot
The following is an example of?
First detectable change. These tests usually report small differences that have little relevance to sensory quality as perceived by consumers.
The following is an example of?
Flowchart
The following is an example of?
Histogram
The following is an example of?
In Process Records - process recording sheet
The following is an example of?
Manufacturing procedure specification
The following is an example of?
Matrix Diagram (Grids)
The following is an example of?
Measured Attribute Change An increase in a non-characteristic attribute (e.g., rancidity in butter) is often more easily detected than decrease of a characteristic attribute (e.g., diacetyl flavour in butter).
The following is an example of?
Normally distributed histogram - all data within lower and upper specification (LS and US). NS is normal specification
The following is an example of?
Normally distributed, but data not centred between LS and US - a good chance that products would fall outside of the US. So adjustments to be made to process
The following is an example of?
Not normally distributed, process prevents exceeding upper limit, but not for lower limit so process not capable of meeting the specification.
The following is an example of?
Pareto Analysis
The following is an example of?
Partial staggered design Batch/es of product is put on test at time zero, and samples are taken off for testing at intervals determined by the expectation of the probable shelf-life
The following is an example of?
Primary, secondary & tertiary packaging
The following is an example of?
Process Decision Program Chart
The following is an example of?
Process check sheets These check sheets are used to create frequency distribution tally sheets that are, in turn, used to construct histograms.
The following is an example of?
Quality scoring/grading/rating method ballot Only of QC use when correct controls are in placed and backed by industry standard and linked to consumer acceptability.
The following is an example of?
Ranking Test Ballot
The following is an example of?
Reversed storage design Samples with different storage times are all analysed at the same time.
The following is an example of?
Scaling method (including targeted scaling) ballot Can be paper based like this example - or (as with all the ballot papers) PC linked and data collected and can be easily analysed via software.
The following is an example of?
Sensory specification semi-quantitative for panellists to use in judgements
The following is an example of?
Statistical Process Control Chart
The following is an example of?
Stored sample design A large batch is put into storage, and samples are drawn at appropriate intervals and held under non-changing conditions (e.g. frozen) until the required storage time has been reached.
The following is an example of?
A *control programme*
The tool to assure the quality targets can be met
• Affinity diagram • Interrelationship digraph • Tree diagram • Process decision program chart • Matrix diagram • Prioritization matrices • Activity network diagram • Gantt chart
There are *eight* management and planning tools:
Right-censoring Left-censoring Interval-censoring
There are 3 main types of censoring that needs to be considered in evaluation of data:
Process average (x̄) Upper Specification Limit (USL) and Lower Specification Limit (LSL). The Process Standard Deviation ( σest). (This can be calculated directly from the individual data, or can be estimated by: σest = R̄ / d2)
To calculate the Cp and Cpk need: (3)
False Even if the scatter diagram shows a relationship, do not assume that one variable caused the other. Both may be influenced by a third variable
True or false If the scatter diagram shows a relationship, one variable caused the other.
False In-process records can be manual, automatic or both - use of process check sheets.
True or false - All in process records are automatic?
False The program will not prevent an adverse situation from occurring. It will, however, help the business and personnel prepare for a possible recall.
True or false - Recalls plans prevent adverse situations from occuring?
1) a *nonparametric* approach - The Kaplan-Meier (KM) methodology, 2) *parametric* methods - use of statistical tests and models (e.g. Weibull, exponential, log-normal, log-logistic) also available to compare different conditions and more generally deal with comparative studies.
Two classical ways of estimating the distribution of failure (or acceptance) times of a product:
Type of data Subgroup size
Type of control chart selection is based on (2)
Microbiologically stable foods, such as biscuits or mayonnaise, will have their shelf-life defined by the changes in their sensory properties. Many fresh foods, such as yogurt or pasta, after relatively prolonged storage may be microbiologically safe to eat but rejected due to changes in their sensory properties. Shelf life in most food products is determined by sensory issues instead of microbiological or chemical concerns.
Type of foods that will have their shelf life tested by sensory methods ?
1) *Internal Benchmarking*: compare to best within organisation to bring all up to best practice. 2) *External Benchmarking*: Compare to other organisation best practise to identify performance gaps to improve on. 3) *Functional Benchmarking*: Compare similar functions (e.g. marketing, QA) to best in ant industry. 4) *Process Benchmarking*: Focus on specific types of operations and processes
Types of Benchmarking (4)
Chemical methods. Instrumental methods. Non-invasive methods. (Measurement data needs evaluation)
Types of detection/ measurement methods in QC
Type I System used for the classification of liquids using an array of sensors with broadly overlapping specificities that is combined with a pattern recognition system. Type II: Reproduces human taste sensations A multi-channel electronic taste-sensing system of several kinds of lipid/polymer membranes connected to a computer which outputs different patterns for chemical substances which have different tastes and similar patterns for chemical substances with similar tastes
Types of electronic tongue (2)
*Primary level models* which describe changes in microbial numbers (growth) with time with set conditions. *Secondary level models* which describe the responses of parameters of primary models to changes in environmental conditions such as temperature, pH or aW *Tertiary level models* are computer programs that enable users to 'interrogate' primary and secondary level models in order to obtain predictions
Types of models in predictive microbiology:
Scatter diagrams *However the relationship that reveals itself on the graph can only be thought of as a Correlation, not Causation.*
Used to evaluate cause and effect relationships.
63.4 74.6
Values, or measurements, less than ___ or greater than ____ are extremely unlikely. These laws of probability are the foundation of the control chart.
Industry standards are organised group attempts to establish given quality limits for a given commodity. Implemented due to pressure from marketing or by specific commodity groups where legal standards do not exist.
What are Industry Standards and why are they implemented ?
These are elaborate management systems that can be used by any organization to develop and achieve its quality objectives. Systems include quality planning and improvement activities, in addition to quality control and assurance activities. (best example of a quality management system is the ISO 9001:2000)
What are Quality Management systems? What do these systems include?
A - Cp <1 - the 6σ process spread is greater than the tolerance B - Cp = 1 the 6σ process is equal to the tolerance. (If perfectly centered, 0.3%of output will be defective) C - Cp >1 the 6σ process spread fits inside the tolerance with room to spare. The process is capable of producing few if any defects if the process is centered.
What are the estimated Cp values for each of the following?
food *poisoning* organisms
What are the following examples of? Salmonella Clostridium botulinum Staphylococcus aureus Clostridium perfringens
Rectangles - A process step Diamonds - Represents a decision branch. The next activity depends on the outcome of the decision D - Represents a delay Hexagons - Represents set up or preparation activity Circles - Shows the flowchart is continued at (or from) another flowchart with the matching letter
What are the meaning of the following symbols used in flow charts?
over shelf life then excessive additives are the defects to concentrate on first to reduce total defects.
What can be determined from this example?
Scatter diagrams
What could be used in the following situations? When trying to identify potential root causes of problems. After brainstorming causes and effects using a fishbone diagram, to determine objectively whether a particular cause and effect are related. When determining whether two effects that appear to be related both occur with the same cause. When testing for autocorrelation before constructing a control chart.
R Values range from +1 to -1 +1 being a perfect positive correlation -1 being a perfectly negative correlation 0 being absolutely no measurable correlation.
What do R values signify in scatter diagrams?
Food Safety
What do the following ensure? no unacceptable health risk associated with a food. harmful substances have been eliminated. microbes educed to an established acceptable level or prevented from exceeding the acceptable level. Food has been prepared, handled, and stored under controlled and sanitary conditions in conformance with regulations.
Food Quality
What do the following ensure? Compliance with specifications: accepted appearance, flavour, texture, etc. shelf life and packaging. conformance to relevant standards. labelling requirements (declared quantity,etc.) free from adulteration/falsification. acceptable for human consumption (deterioration or decomposition)
A focused methodology for listening to the customer and then effectively responding to those needs in the product. So in QFD, quality is a measure of customer satisfaction with a product or a service.
What is Quality Function Deployment (QFD)?
A method for monitoring, *controlling* and, ideally, improving a process through statistical analysis.
What is SPC (Statistical Process Control) used for ?
Total Quality Management
What is TQM?
A statistical process control chart is a graphical representation of a *quality characteristic* that has been measured or computed from a sample vs. the sample number or time
What is a control chart ?
A control point is a step in process or formulation where small changes can cause the finished product to be illegal or rejected by the consumer. Self-imposed because of desired label statements to ensure that specification is met Defined by regulation when product identity is of concern.
What is a control point?
A critical control point is a step in process or formulation where small changes can cause the finished product to be a health hazard. Defined by regulation when public health is of concern.
What is a critical control point?
A picture of the separate steps of a process in sequential order
What is a flow chart ?
Product recall is to return product from the distribution system.
What is a product recall?
GANTT Charts
What is defined by the following *Relationships among the project tasks, along with time* constraints The horizontal axis of this chart shows the units of time (days, weeks, months, etc.) The vertical axis shows the activities to be completed Bars show the estimated start time and duration of the various activities The chart can be modified to include a milestone symbol that represents an event. These charts are also known as milestone charts.
Total Quality Management
What is defined by the following: A philosophy of perpetual improvement. Seeks to improve the quality of products and services through ongoing refinements in response to continuous feedback
Quality Control
What is defined by the following: Involved with inspecting, testing, and monitoring associated with raw materials control, process control, and finished products control. So evaluation of the quality - does the product meet customers expectations.
Matrix Diagram (Grids)
What is defined by the following: *Used to analyse the correlations between two groups of ideas* Examine relationships between two or more sets of items. It consists of a number of columns and rows whose intersections are compared to find out the nature and strength of the problem. *Quality function deployment (QFD) is an enhanced version.*
Activity Network Diagram
What is defined by the following: An arrow diagram, is a network technique using nodes for events and arrows for activities for project planning, scheduling, and monitoring. It is similar to the Critical Path Method (CPM) and the Program Evaluation and Review Technique (PERT)
Benchmarking
What is defined by the following? A continuous systematic procedure that measures a company's product and process against industry leaders.
House of Quality for voice of customer
What is defined by the following? Identify and classify customer desires - the wants or whats. Then identifies the importance of each what Then identifies processing characteristics (or ingredients) which may be relevant to those desires - the hows. assigns objectives and priorities for the system requirements. Data is entered onto a grid with whats on one dimension and hows on the other dimension. The grid is filled with the weights assigned to the whats where those characteristics are affected by the hows across the top of the matrix. At the bottom of the grid, the column is summed, which allows for the system characteristics to be weighted according to the stakeholder characteristics.
A *Dendrogram* / Tree diagram
What is defined by the following? A technique for mapping out a full range of paths and tasks that need to be done in order to achieve a primary goal and related sub-goals
Interrelationship Digraph
What is defined by the following? Designed as a means of organizing disparate ideas, usually (but not always) ideas generated in brainstorming sessions Used to attempt to define the *ways in which ideas influence one another*, while affinity diagrams seek to simply arrange related ideas into groups.
Process Decision Program Chart
What is defined by the following? Maps out all conceivable events and contingencies to discover feasible countermeasures to minimize nonconformities in the manufacturing process.
1) Moderate correlation 2) Strong correlation
What is demonstrated by the following?
A scatter plot matrix diagram compares more than two variables
What is demonstrated by the following?
High Specification - High Quality High Specification - but Low Quality
What is demonstrated by the following?
House of Quality
What is demonstrated by the following?
Out of Control - If 2 out of 3 successive points fall in the area that is beyond 2 σ from the mean, either above or below
What is demonstrated by the following?
Out of Control - If 4 out of 5 successive points fall in the area that is beyond 1 σ from the mean, either above or below
What is demonstrated by the following?
Out of Control - If 8 or more points fall on either side of the mean (some organisations use 7 or 9)
What is demonstrated by the following?
Out of Control - If one or more points falls outside of the upper control limit (UCL), or lower control limit (LCL).
What is demonstrated by the following?
Out of Control - If there is a run of 6 or more points that are all either successively higher or successively lower
What is demonstrated by the following?
Out of control - If 15 points in a row fall within the area on either side of the mean that is one standard deviation from the mean
What is demonstrated by the following?
Turn the distribution curve sideways, and the lines denoting the mean and ± 3σ are extended. - This gives the basis of the Control Chart.
What is demonstrated by the following?
When an out-of-control condition occurs, the points should be circled on the chart, and the reaction plan should be followed Successful corrective action should also be noted on chart
What is demonstrated by the following?
1) Positive correlation 2) Negative correlation 3) No correlation
What is demonstrated by the following? 1) 2) 3)
Basic concepts of Quality Improvement
What is described by the following Improvement Distinguished from Control (Reduction of waste) All Improvement Takes Place Project by Project (a problem is identified) Is Applicable Universally Extends to All Parameters (product or process redesign, productivity)
Food grading
What is described by the following Involves the inspection, assessment and sorting of various foods regarding quality, freshness, legal conformity and market value
Consumer or Grade Standards:
What is described by the following Represent consumer characteristics in the foods required by the consumer.
Electronic nose
What is described by the following: Now have biosensors based on proteins from the olfactory system. Some can now incorporate GC detection systems.
NIR
What is described by the following: Once set up - inexpensive, non-invasive, rapid and several components can be measured. Proximate analysis for quality - ingredients testing and process checking and product check possible. Research into use for microbiological screening.
Raman spectroscopy
What is described by the following: Some vibrational modes same as IR, some different. Minimal sample prep. Compatible with wet sample. Any sample fluorescence interferes
Select factor/s that are kinetically active during the deterioration process Run kinetic study at levels of selected accelerating factors so that the rate of deterioration is fast enough Estimate values from the most appropriate kinetic model and extrapolating the data to normal storage conditions Use the extrapolated data or the kinetic model to predict shelf-life at the actual storage conditions
What is described by the following?
Pareto diagram
What is described by the following? A technique used to identify the *degree* of importance of quality problems. Used at various stages in a quality improvement programme to determine which step to take next. Ranks the causes of defects in decreasing order based on their percentage.
Check Sheets
What is described by the following? Consists of lists of items and some indicator of how often each item on the list occurs. Answers the questions posed by the investigator: They direct the attention of the data collector to items of importance. Simple versions called confirmation check sheets. Data collection is easier by providing pre-written descriptions of events likely to occur.
Quality Assurance systems
What is described by the following? Provide confidence to stakeholders (customers, regulatory agencies) that the company is capable of meeting the food quality and food safety requirements.
Electronic tongue
What is described by the following? Sensor types (3-12 in arrays): Ion selective glass electrodes (beverages and mineral water) Metal electrodes (tea flavours and heavy metals) Noble metal layers in flow stream arrangement
Ultrasound - methods based on listening
What is described by the following? To analyse food systems based on the noises they produce Sound waves generated by the system may be well outside the auditory range We can make artificial ears that are more accurate and efficient.
Paired comparison methods(e.g. 2-AFC, simple difference test)
What is described by the following? Easy to set up, train panellists and analyse data. Can be very sensitive to small differences. The test can determine simply if the presented 2 samples are different -limited in this mode as other tests better (duo or triangle tests) More usefully the test can determine if 2 samples are different in a particular attribute (2-AFC method - 2-alternative forced choice method)
Histograms
What is described by the following? Graphically summarise and display the distribution of a process dataset. To construct: Segment the range of the data into equal-sized bins (i.e., segments, groups, classes) The vertical axis is the frequency (i.e., the number of counts for each bin) The horizontal axis is labelled with a range of the response variable The number of data points in each bin is determined and the histogram constructed Note : The user defines the bin size
Electronic nose
What is described by the following? Has an array of electronic chemical sensors. Capable (when 'trained') of recognising simple or complex odours
SPC systems
What is described by the following? Requires support from top management Most effective when it is known that senior managers review charts and make comments. Most effective if charts are posted on the "shop floor" so they are visible to operators This also makes them accessible to problem solving teams Complete ownership at all levels. Initial systems set up can be expensive - however the return on the investment can be high.
Initial rate approach -accelerated shelf life testing
What is described by the following? Small changes in deterioration is measured after a relatively short time at actual storage conditions Used when accurate and sensitive analytical methods can be used to measure deterioration processes Kinetic data is obtained from the initial stage of the process Shelf-life is predicted from an equation that models deterioration changes, such as concentration of a component of interest, with time
In/out (pass/fail) method
What is described by the following? Use specification sheet to lessen personal preferences in judgement. Can add a section to give reason for out Best if 25 or more panellist can be used. Can be used with: raw materials, interim products finished products.
Affinity Diagram
What is described by the following? Used to gather and organise ideas, opinions, issues, from a list, usually generated through brainstorming, into groups of related thoughts that make sense and can be dealt with more easily A means of data reduction in that it organizes a large number of qualitative inputs into a smaller number of major categories
In-line is a form of on-line continuous system: An on-line system which takes a portion of material for analysis from the process line by using a sampling branch.
What is meant by 'in - line' measurement?
A sample from the process line is transported (manually or automatically) to a measurement device not connected to the process line, where a wide range of analytical operations can take place.
What is meant by 'near - line'/ 'at line' measurement?
A sample is taken manually from a process line and measured with a device in a laboratory.
What is meant by 'off - line' measurement?
A probe positioned within the line, on the outside surface of the process line or on a transparent window in the line where an observation can be made.
What is meant by 'on - line' measurement?
Environmental conditions are accelerated by a known factor so that product deteriorates at a faster than normal rate.
What is meant by Accelerated shelf life testing?
*the last date of maximum high quality.*
What is meant by Best before or best if used by date?
Extra standards established by various segments of the food industry that give their products a competitive marketing advantage. Represent a consumer image and may become a symbol of product quality. Generally used by private companies or supermarkets and vary - aim to penetrate many more markets based on pricing, consumer preference and tastes.
What is meant by Company/Voluntary Standards? Why are they implemented? Most commonly used by?
*The date on which the product was placed on the shelf by the retailer.* not often seen on packs on shelf sometimes visible on supermarket fresh
What is meant by Display Date?
Product shelf life based on both distribute on and home storage conditions.
What is meant by Distribution Abuse Test?
Average length of time which a product spends in distribution. (measures "required" instead of "true" shelf life)
What is meant by Distribution Turnover time?
Samples taken from distribution channels and laboratory tested to determine the quality.
What is meant by End point study?
Good Manufacturing Procedures
What is meant by GMP?
Total cost throughout product life: planning, design, acquisition and support, and any other costs because of owning the product
What is meant by Life Cycle Cost?
Published data of analogous products.
What is meant by Literature study?
Plan - Quality principles, factors affecting quality Do - Personnel, Policies & Procedure Check - Sample Guidelines, Error Categories Act - Review, Revise, Communicate, Monitor
What is meant by PDCA?
Plan - Plan change Do - Implement the change Study - Impact of the change Act - Make another small change
What is meant by PDSA?
*The date on which the product was packed into its primary package.* It does not provide any specific information as to: the quality of the product when purchased, or how long it might retain its quality after purchase.
What is meant by Pack Date?
The ability of a process to meet specifications (customer expectations) Measured by indexes that compare the spread (variability) and centring of the process to the upper and lower specifications.
What is meant by Process Capability ?
Targeted Difference from control (TDFC) method For when it is known that there are known changes between batches. (If sweetness changes between batches - then TDFC is used to determine the difference in sweetness)
What is meant by TDFC method and when is it used?
*the date after the which the food should no longer be at an acceptable level of quality.*
What is meant by Use by date or expiration date?
*the last date on which the product should be sold in order to allow the consumer a reasonable length of time in which to use it.*
What is meant by pull, display until or sell by date?
Primary package encloses the food and has direct contact with the product and displays information - e.g.: film jar bottle carton box can
What is primary packaging?
Secondary package encloses groups of primary packed products.
What is secondary packaging?
Tertiary packaging encloses groups of secondary packed products for bulk handling, storage and transport
What is tertiary packaging?
The control plan is the centralized document to keep track of the status of all significant process characteristics
What is the Control Plan?
Product Formulation/Recipe Specification
What is the following an example of?
Product Standards - Specification
What is the following an example of?
Statistical process control chart
What is the following?
A plotted point that falls outside the control limits signals a possible change in the process, possibly due to some "assignable cause" The cause of the "out-of-control" reading should be investigated and process adjustments made where necessary.
What is the significance of a plotted point that falls outside the control limits?
Shelf life studies
What should be conducted in the following examples? New product launch Package re-design/New packaging Challenge the lifespan Collect data for validation Change in ingredients Change in supplier materials As part of your QA/QC Program Is your current package still performing?
Every food organisation is susceptible to potential product recall.
What type of food organisations are subject to product recall?
When the process in control and data is normally distributed
When can the process can be compared to the tolerance to see how much of the process falls inside or outside of the specifications?
If the packaging is in direct contact with the food
When might chemical migration be an issue in food packaging?
When it cannot be used... A large number of samples is used when there are many factors and levels in the experiment Difficulty in recruiting a large number (min 100 for statistical models)
When not to use survival analysis:
Coliforms E. coli
When products subjected to heating use _________ and _______ to show and control post process contamination.
Method of choice when... Consumers are used to the task of accepting or rejecting samples. Information obtained is directly related to everyday eating experience
When to use survival analysis:
Can have Action at +/- 3 σ . Warning at +/- 2 σ
When would action be required? WHen would a warning be demonstrated?
1) Variable Data 2) Attribute Data
Which is Variable Data? Which is Attribute Data?
Ion Selective electrodes
Which method is described by the following: Electrochemical sensors ISE can measure specific ions in solution
Quality Control - Detection Quality Assurance - Prevention Quality Management - Direction & Control
Which of the following are associated with Detection, Prevention, Direction & Control? Quality Control Quality Assurance Quality Management
Scaling method (including targeted scaling)
Which sensory method does the following describe? Needs a R&D quantitative descriptive profiling panel. Or extensive training (and monitoring) to other panellists. Not popular in QC if there is training requirement. Select attributes that are known to change in processing for daily monitoring. Targeted if only 1 attribute tested Data analysis is by statistical analysis - so statistical analysis training for test co-ordinator Useful for testing particular attributes that change but are key to consumer liking product. Samples coded with 3 digits and presented to panellists in a randomised balanced design
Ranking Test
Which sensory method does the following describe? Simple to set up, little training for panellists, simple analysis. Not popular in QC due to manner of the questions. Based on some attribute/s the panellist is asked to put samples in order (rank) (BSI, 1989) of e.g. sweetness or creaminess. A potential issue may be linked to several attributes which limits usefulness of the test. If one attribute is the main issue, then useful. Present trained and screened panellists with 4 or 5 samples in a random order and they rank in order of the specific attribute. One of samples is the verified control and often a "hidden" control is included as a check. Minimum number of panellists is 5 , but need 30 for quality data.
Difference from control (DFC) method
Which sensory method is described by the following: Easy to set up Short training for panellists. Monitor by use of a "hidden control" to test (for validity should be scored 0 or 1). Some companies just use mean values. Can employ statistical significance analysis (then 18 panellists) - more tricky.
Triangle Test
Which sensory test is described by the following? Not ideal for QC - sensitive to small changes and so gives false positives. In QC where products affected by very small changes. Panellists are trained and screened. 3 samples (3 digit code) presented and told one is different and need to identify the different one. As there are 6 possible presentation orders (AAB, ABA, BAA, BBA, BAB, ABB) best with groups of 6 assessors. ISO4120:2004 details panellist requirements. Can add a question about what the difference is.
Quality scoring/grading/rating method
Which sensory test is described by the following? Common method for QC. Often developed for specific product in a specific company. Training and experienced panellists used - method relies on panellists memory of the ideal product. Panellist training must include the meaning of the grades, scores or ratings. Often used for commodities (e.g. milk) - which have a supported industry consensus. Disadvantage is expert assessment may not agree with consumer opinion. If panels are small and not well trained then often get panellists opinion Better used in NPD.
Electronic nose
Which technique has been used in the following applications: Differentiation of spices. Classification of green tea. Identifying spices in a 4 spice mixture. Monitoring wine fermentation. Fish freshness. Meat freshness. Classification of vegetable oils. Cheese maturity Differentiation of coffees. Italian vinegar classification. Authentication of wine. Classification of fruit and fruit ripeness. Monitoring of packaging quality
Ultrasound - methods based on low amplitude sound
Which technique is described by the following ? Important for assessing fermentation, emulsions, sugar content in juices
Ultrasound - methods based on *low amplitude sound*
Which technique is described by the following? Capabilities: Monitoring of *online* food processes Detection of *physico-chemical properties* Properties can often be determined analytically, but for complex foods we can resort to empirical approaches
Ultrasound - methods based on *low amplitude sound*
Which technique is described by the following? We can measure the speed of sound accurately, usually to within 0.1 ms-1 Real-time, non-invasive and non-destructive
Ultrasound - methods based on *low amplitude sound*
Which technique is described by the following? Key features: *Does not significantly modify* the material under examination Usually *does not require sample dilution* Can probe *opaque foods* Can be *non-invasive*
Reflectance spectroscopy From this, can calculate chromaticity coordinates X + Y and create a 2D model - can be used for colour matching, colour difference etc.
Which technique uses the following: L a* b* model for colour matching L - lightness of colour A - redness & greenness B - blueness & yellowness
Descriptive tests
Which type of sensory test is described by the following? Appropriate in NPD, and QC, sensory specification. Require the definition, evaluation and understanding of a product's characteristics. High levels of sensory acuity and training for assessors.
Preference and acceptability tests
Which type of sensory test is described by the following? Establish whether product differences are recognised and are improved with respect to liking or acceptability. Assessors representative of target consumers and no training
Discriminative tests
Which type of sensory test is described by the following? Useful in QC, and shelf life testing. Depends on assessor ability to detect an recognise differences
1 - Discriminative 2 - Descriptive 3 - Hedonic
Which type of tests are 1, 2 & 3
Involve everyone - Suppliers, personnel, customers.
Who should TQM involve?
Powerful medium for communication. Corrective actions noted on charts: Process shifts, out-of-control conditions Notes help connect cause and effect in the minds of all who use the chart.
Why are the best SPC charts covered in notes?
Overall graphics must be representative and not misleading.
Why are there many requirements for government regulation on food labelling? (even extend to specifying size and type of printing)
To develop understanding of how a process is done. To study a process for improvement. To communicate to others how a process is done. When better communication is needed between people involved with the same process. To document a process. When planning a project.
Why/ when are flowcharts used ? (6)
moisture
Yeast or mould counts essential with low/restricted ________ levels.
Food *spoilage* organisms
Yeasts/ moulds are examples of:
A basic food process flow chart for potato slice drying • Basic flow chart - a basic organisation of the process without giving details of every step involved or its particular conditions
Ŧhe following is an example of?
Prioritization Matrices
Ŧhe following is an example of?