NFSC112 Exam 3
What is the effective agent in Electrolyzed Oxidizing (WO) water?
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What are examples of food toxins from industrial contamination?
-Beer, fish, meat products, deep fried potatoes
Why food labeling is necessary?
-Compare one food with another -Choose foods that provide the balance of nutrients your body needs -Plan meals
Which substance is responsible for the toxicity of Cyanogenic Glycosides? What are the factors affecting the release of this substance in food?
-Amygdalin is responsible for the toxicity -presence of enzyme -water -physical conditions
What are different factors affecting freezing rate?
-Driving force: temp of freezing medium, thermal conducting characteristics that transfer of medium, contact velocity of heat transfer of medium with product -Resistance: product thickness, product geometry, composition, resistance to heat transfer of the food packaging
What is Pulsed Electric Fields? How does PEF inactive microorganisms? What are some issues associated with PEF concerning microbial inactivation?
-High voltage pulses electricity between electrodes to treat fluid foods. -Inactive microorganisms by continuous process -spores, air bubbles, particulate matter
What is inactivation mechanism for cold or non-thermal plasma? What are their applications in food industry?
-It is the damage of cell membrane wall
What foods are associated with acrylamide? How can we reduce the exposure to acrylamide?
-Potatoes (french fries, chips), grains (breakfast cereals, cookies, toast) -Roast potatoes instead of frying, boiling instead of frying
Why do you think consumers are hostile towards biotechnology-derived foods?
-Potential risk for human health: toxins and allergens -Environmental safety: passing altered genes to wild/weed plants
What are the different recommended thawing methods? Should thawing be rapid or slow? Why?
-Thaw in cooler/fridge: relatively slow -Microwave -Cold running water -Cook from frozen state: rapid
How to interpret the sentence "dose makes the poison"?
-chemicals that are naturally present in foods are fine, but too much is bad vitamin a: good at small dose, toxic at high dose
What are the detrimental changes that could occur in foods during refrigerated storage?
1) Chill injury: physical damage caused to fruits and vegetables from too low fridge temps 2) Storage temp below 13°C slow down the activities of natural ripening enzymes and result in poor colors in tomatoes and bananas 3) Exchange of odor/flavors between food: butter/milk absorb odors from fish & fruit 4) Nutrient loss: Vit C (broc, asparagus) loss of sugar in sweet corn 5) Texture: loss of firmness in fruits & veggies 6) Color changes 7) Fat oxidation 8) Flavor losses 9) Lumping & caking powders 10) Microbial deterioration
What are the different methods for accelerating cooling process?
1) Evaporative cooling: spray w/ water, subject food to vacuum (ex: leafy vegetable) 2) Nitrogen Gas: from evaporating liquid nitrogen for produce 3) Heat exchangers: thin platers where warm bulk liquid foods pass next to chilled, cooling coils in vat of liquid food
Describe the general process of gene cloning
1) find organism with the desired gene 2) cut genome into fragments 3) insert fragments into vector 4) insert vector into host cell 5) isolate cells with the desired gene
How major food allergens are listed? How food allergen advisory statement is written?
1) in parenthesis following the name of ingredient ex: flour (wheat) 2) immediately after the list of ingredients with the word "contains" ex: contains wheat Advisory statement: ex --> "may contain (allergen) or "produced in a facility that also uses (allergen)
What is the difference between absolute and relative nutrient claims?
Absolute:defined in the 9 CFR for meat & poultry products and 21 CFR for FDA products Product must meet requirement for the claim or you can't use the claim on your label Relative: claims compared to another product & % difference is on the label. Comparison product depends on which claim use
What is the Acceptable Daily Intake of Aspartame set by FDA? For an adult (150 lbs), how many cans of diet soda (12 oz) is needed to reach the ADI of Aspartame?
Acceptable intake is 50mg/kg 20 cans of soda
What are some examples of naturally occurring animal toxins? What are the sources of each toxin?
Animal toxins (seafood) -scrombroid poisoning: spoiled fish -saxitoxin: harmful algal bloom -ciguatoxin: symptoms within hours, vomit, diarrhea -tetrodotoxin: puffer fish
Define food biotechnology
Applying technology to modify genes of animals, plants, and microorganisms to create species which have desired product marketing or nutrition related properties
What are the advantages of rapid freezing over slow freezing?
Better quality
What are different categories of food additives?
Colorants, flavoring, flavor enhancers, antioxidants, chelating agents, antimicrobials, curing agents, fat substitute, nutrient substitute, enzymes, anti caking agents, texture improving agents, pH control agents, sweeteners
What do you understand by "recombinant DNA technology"?
Deliberately modifying the characteristics of an organism by manipulating its genetic material
What are the four components of risk assessment? Briefly explain
Hazard identification Hazard characterization Exposure assessment Risk characterization
How do you define "hazard" and "risk"? What do you mean by "hazard-based" and "risk-based" food safety systems?
Hazard: biological, chemical or physical agent in food with potential to cause adverse health effect Risk: a function of the probability of an adverse heath effect and severity of that effect in food Hazard based: presence of a hazard is ground for considering a food unsafe Risk based: consider the probability and likely consequences of an exposure to determine if a food is unsafe
What is the difference between a law and a regulation?
Law: congress votes to approve bills, president signs approved bill into laws, agencies (FDA and USDA) write rules to implement laws Regulation: rules based on interpretation of law, has force of law
What is the lethal mechanism of HIP Polychromatic Light? What are the challenges when applying in food industry?
Lethal mechanism involves energy absorption by conjugated C=C bonds in proteins & nucleic acids
What is the mechanism of inactivation for High Pressure Processing? What are the critical process parameters in HPP?
Mechanism of inactivation: disruption of cellular membrane, denaturation of proteins. Critical Process: pressure magnitude, treatment temperature and treatment time.
How are foods produced using genetically engineered plants regulated in the US?
No labeling requirements for transgenic crops
What is nutritional panel? What does it contain?
Nutritional panels are required on all products unless it falls under one of the exemptions It contains guidelines for the format and serving size
What is risk communication?
Ongoing process with different skate holders throughout the process of analysis
What are Principal Display Panel (PDP) and Information Panel (IP)? Where are these located?
PDP: statement of identity --> the panel that consumers see first IP: where you find nutrition facts, ingredient statement, place of business --> first usable panel to the right of PDP
What is the difference between qualitative and quantitative risk assessment?
Qualitative: descriptive model, presents evidence to support a statement about risk Quantitative: mathematical model, evaluates and estimates the health risk
What is the difference between refrigeration and freezing? Is the freezing temperature of our water and food the same? Why or why not?
Refrigeration: preservation with the least change in taste, texture, nutritional value Frozen Stage: proper freezing without causing major changes in size, shape, texture, color/flavor The water component of a food freezes first and leaves the dissolved solids in a concentrated solution
What is Risk Analysis? What are the three components of risk analysis process? Briefly describe those and give examples of actions performed for each component.
Risk analysis: gathering and evaluating data related to a hazard, then using that knowledge to manage the risks associated with the hazard Risk assessment: scientific inputs Risk management: decisions involving policies and values Risk communication: interactive exchange of information and options concerning risks
What is the difference between risk management and risk assessment?
Risk management CONTROLS the risk Risk assessment MEASURES the risk
What is a guidance document?
Suggestions to industry based on interpretation of laws
Why foods should be regulated?
To ensure consumer safety
Why is it important to perform risk analysis in food safety area?
To improve the quality of our thinking before a decision is made. To assure a safe domestic and international food supply to protect public health
What are toxins? What are the sources of food toxins?
Toxins are harmful to a specific organ/system Processed foods that are full of chemicals and additives.
What are transgenic plants? Name 5 plants and describe the modifications that make them different. What are the benefits of these modifications?
Transgenic plants: plants that have been genetically engineered, plans with new characteristics Examples: Tomato: delayed ripening Corn: control over starch structure Corn, canola: control over lipid profile Rice: increased provitamin A Peanut: elimination of allergens Benefits: improved quality, promote human health, improved flavor
What are the top two federal agencies that regulate food safety in the US?
US Code (Public & Private Laws) Code of Federal Regulations (CFR)
Describe two food processes that rely on microbial biotechnology. List two applications of diagnostic biotechnology.
Xanthin Gum: -prepare feed -inoculate with xanthamonas campestris -purify xanthan gum -use as food ingredient Conversion of Starch: -gelatinize starch -add microbial amylases -convert starch to various products (ex: glucose) -use as food ingredient
What are the advantages of non-thermal processing?
preservation, safety, retain color, flavor, improve texture