FOOD SAFETY EXAM I and II

lag phase

"flat" period of adjustment, enlargement; little growth

$77.7 billion. • Estimates are that foodborne illness costs the food industry between _ annually

$152 billion and $1.4 trillion

• Annual health-related costs for foodborne illnesses are

$51 billion to $77.7 billion.

Bacteria most often grow in food with aw

0.85

Most fresh foods: aw

0.97 - 0.99

The body has some defense mechanisms...

1. An acidic stomach 2. An active, intestinal immune system 3. Residential intestinal flora 4. Highly concentrated bile salts and digestive enzymes 5. Mucus coating 6. Peristaltic action—able to reduce the ability of certain pathogens to colonize

Two ways of expressing the water content of food

1. Moisture content • Amount of water/total weight 2. Water activity • Water available for chemical reactions and microbial growth

Controlling chemical hazards involves what two things?

1. Naturally occurring hazards that are potentially in the food 2. The types of chemical hazards that may be present in a facility • Develop a plan to eliminate and/or minimize these hazards

Top five pathogens contributing to domestically acquired foodborne illnesses

1. human norovirus 2. nontyphoidal Salmonella spp. 3. Clostridium perfringens 4. Campylobacter spp. 5. Staphylococcus aureus

Top five pathogens contributing to domestically acquired foodborne illnesses resulting in death

1. nontyphoidal Salmonella spp. 2. Toxoplasma gondii 3. Listeria monocytogenes 4. human norovirus 5. Campylobacter spp.

Top five pathogens contributing to domestically acquired foodborne illnesses resulting in hospitalization

1. nontyphoidal Salmonella spp. 2. human norovirus 3. Campylobacter spp. 4. Toxoplasma gondii 5. Shiga toxin-producing E. coli (STEC) O157:H7

In each year, how many people get die from foodborne illnesses?

3,000

Pathogenic bacteria grow well in food that is slightly acidic or nearly neutral ph is

4.6 to 7.5

"Temperature Danger Zone" (Fahrenheit and Celsius just in case)

40˚F and 140˚F (4.5˚C and 60˚C)

In each year, how many people get sick from foodborne illnesses?

48 million

Vegetative Cells

Active Normally growing and functional Easier to destroy and control via sanitizers/disinfectants, temperature, pH, etc.

_ raw foods normally contain microorganisms that will eventually cause spoilage unless they are controlled or destroyed

All

CONTROL BY FOOD PRESERVATION TECHNIQUES

Canning/thermal processing Pickling Curing Dehydration Fermentation

Chemical Contaminants (definitions)

Definitions: • Chemical hazards associated with food include: • Naturally-occurring chemicals (Toxins) • Unintentional or incidental chemical additives • Intentionally-added chemicals Naturally-occurring chemical hazards: • Toxins in some species of mushrooms • Toxins found in or produced on certain types of fish and shellfish • Mycotoxins produced by molds Unintentionally Added Chemicals: • Agricultural chemicals such as pesticides, herbicides, animal growth regulators, and antibiotics used in the production of the food product. • Cleaning chemicals • Maintenance chemicals such as lubricants Intentionally Added Chemicals: • Examples include preservatives, colorants, nutritional additives

bacterial spore

Dormant or resting stage (i.e., no metabolic activity) formed in response to adverse environmental conditions. • Help ensure the survival of the organism in times of environmental stress. • Can return to active bacteria when proper conditions exist. • Highly resistant

True or False: Cooking reduces or eliminates the chances of a person with a food allergy having a reaction to the food eaten.

False Cooking does not reduce or eliminate the chances of a person with a food allergy having a reaction to the food eaten.

Bacterial Spores'

Inactive Dormant structure produced as a result of unfavorable environmental conditions Hard to destroy by sanitizers/disinfectants

Infiltration is easy due to...

Large surface area of the GI tract Presence of large amounts of nutrients for survival and growth Absorptive capacity of GI tract

'infectious dose'

Organism must have multiplied in food to a high enough level to cause illness • ≥ 10 cells for Shigella • ≥ 18 viral particles for human norovirus • ≥ 1,000 cells for Salmonella spp.

Spoilage Microorganisms

Organisms that cause food to go 'bad' or become inedible ▪ include molds, yeasts, and bacteria

Some of the factors that influence development and severity of infections are:

The immune status of the person Efficiency of the pathogen in attaching to and penetrating the target tissue The number of pathogenic organisms entering the body The differing symptoms, duration, and severity of foodborne diseases makes diagnosis and tracking of occurrences difficult

log phase

The period of exponential growth of bacterial population.

generation time

The time that a single cell takes to divide into two Bacteria have the shortest followed by yeasts and molds Dependent on types of bacteria and environmental factors

True or False: Absolute safety is unattainable.

True • Great gains at modest cost, but further gains become increasingly expensive • No amount of money will buy complete safety

Intoxication occurs when

a person eats a food containing a toxin

Food handling employees should be _ work if they are sick, vomiting, have diarrhea or are showing symptoms of a sore throat or fever.

absent from

• Potable water must _ be used when water is an ingredient.

always • Even though some processing procedures might be sufficient to eliminate any contamination that might be in the water, this is not always the case and should not be relied on to assure safety. • Water may be added as an ingredient in the form of ice or steam. • Anytime this is the case, these products should be produced, handled, and stored to protect them from contamination.

"bacterial growth"

an increase in the number of bacteria present, not to an increase in the size of individual cells • Reproduce by splitting in two; therefore, numbers double rapidly. • For many bacteria, this splitting occurs on an average of every 20-30 minutes and is known as the 'log phase'

physical hazard

any potential harmful extraneous matter not normally found in food Examples: • metal fragments • glass particles • wood splinters • rock fragments • stones • bone fragments (meat and poultry)

Most troublesome microorganisms for food processors since they can grow without a living host are called what?

bacteria

Which of the following is not a physical hazard? (2 answers) bacteria hair fingernails plastic wood viruses glass rock fragments

bacteria, viruses

The microorganisms of primary concern to the food processor are

bacteria, yeasts, and molds • They can grow in the food or the processing environment under suitable conditions Other microorganisms of concern • Viruses • Parasites

Because bacterial spores can survive adverse conditions, they can be present in food _ processing treatments are applied.

before, during, and after Therefore, the time it takes to heat and/or cool product during processing is important

• Bacteria can be classified as spore formers non-spore formers

both

facultative anaerobic

can live with or without oxygen

Infection

caused when a pathogen present in food is ingested and then multiplies in the body E.g., Salmonella, Campylobacter, norovirus

Toxicoinfection

caused when a pathogen produces a toxin in the bod E.g., Clostridium perfringens, Shiga toxin-producing E. coli

Intoxication

caused when certain toxin-producing microorganisms present in food multiply, sporulate, or lyse, thus releasing the toxin in food E.g., Staphylococcus aureus, Bacillus cereus, Clostridium botulinum

If the product remains in a temperature range favorable to bacterial growth too long, the spores will

change to vegetative state and start reproducing (outgrowth of spores)

Foodborne disease (causes)

damaging host cells interfering with metabolism of host inducing a response in host that is harmful

Pathogens

disease-causing microorganisms that cause illness Foodborne pathogens (e.g., viruses, bacteria, parasites) are biological agents that can cause a foodborne illness event.

Microorganism acts directly on the intestine

either infecting it or invading the intestine to infect other body parts

Toxin disrupts a particular target such as

gastrointestinal tract central nervous system Symptoms vary from diarrhea and vomiting (Staphylococcus aureus toxin) to severely disrupted muscle and nerve function (Clostridium botulinum toxin)

Foodborne disease

illness contracted from eating contaminated food or beverages

Control by temperature

keep product temperatures above or below the temperatures where bacteria grow.

Foodborne illness can result in _

legal action and damaged reputation

anaerobic

live and grow in the absence of oxygen

The more time bacteria spend at temperatures optimum for their growth, the more opportunity MID levels. What does MID stand for?

minimum infective dose

• The source of potable water to your facility must be from what two things?

municipal supply or private well

_ water should be identified and should have a separate system for distribution, storage, etc.

non-potable

When does a foodborne disease infection occur?

occurs when a person eats food containing pathogens

If a plant receives water from a well, the well should be tested a minimum of how often?

once a year

stationary phase

period of equilibrium; microbial deaths balance production of new cells

• aw of food can be lowered by:

physically removing the water adding ingredients that bind water

death phase

population is decreasing at a logarithmic rate

aw = 1

pure water

Control by pH

reducing the pH below the minimum level for growth

aerobic

require oxygen to survive

Keep raw foods _ ready-to-eat or cooked foods

separate from • Inspect all raw materials coming into the facility to determine if they are acceptable • Use equipment specifically designated for working with raw materials and use this equipment only with these items. • Train staff on appropriate procedures for handling of raw materials.

Bacteria are ______________ celled organisms.

single

Under microscope appear in a variety of shapes or forms, but those of primary concern are mainly what two shapes?

spherical (cocci) or rod-shaped (bacilli)

When conditions are adverse, some bacteria form

spores Dormant or resting stage in the normal growth cycle of some bacteria Help ensure the survival of the organism in times of environmental stress Can return to active bacteria when proper conditions exist Highly resistant

Why is the human body a good place for microorganisms to live and grow?

the human body is a warm and moist • Employees who do not follow sanitary practices contribute to contamination of the foods they touch. • Employees that are ill or have been exposed to certain illnesses may transfer the microorganism involved to food.

foodborne disease outbreak

the occurrence of two or more cases of similar illness resulting from the ingestion of a common food

Contamination

the presence of harmful substances in food

Microbiology

the study of all living organisms that are too small to be visible with the naked eye. This includes bacteria, archaea, viruses, fungi, prions, protozoa and algae, collectively known as 'microorganisms' or 'microbes'.

Cross contamination

the transfer of harmful microorganisms or other contaminants to food from other foods, cutting boards, utensils, hands, etc. Prevention: Although the growth of microorganisms is slowed in refrigerators and freezers, it is not stopped. These areas need to be cleaned regularly.

aw = 0

totally dry

• If water is re-circulated for re-use, it should be _ so it is not a safety risk.

treated and maintained

True or false: bacteria Cannot be seen, smelled, or tasted

true

Just like food processing equipment, employees must keep clean by _.

washing their hands frequently and wearing clean clothes

Potable Water

water that can be consumed without concern for adverse health affects, i.e. drinking quality water. By definition, potable water does not have to taste good but obviously a plant does not want to use water that would add an undesirable taste to the product(s)

Cross-contact

when an allergen is inadvertently transferred from a food containing an allergen to a food that does not contain the allergen.

Clostridium perfringens

• A spore-forming bacterium that is found in many environmental sources as well as in the intestines of humans and animals. • C. perfringens is commonly found on raw meat and poultry. • It prefers to grow in conditions with very little or no oxygen, and under ideal conditions can multiply very rapidly. • Some strains of C. perfringens produce a toxin in the intestine that causes illness. • Illness is caused by eating food contaminated with large numbers of the bacteria that produce enough toxin in the intestine to cause illness. • During cooling and holding of food at temperatures from 54°F-140°F, the bacteria grows. • If contaminated food is served without reheating to kill the bacteria, live bacteria may be eaten. • The bacteria produce a toxin inside the intestine that causes illness • Characteristics • Causes foodborne infections • Requires little or no oxygen • MID = greater than 108 (100,000,000) cells • Prevalence • Beef, poultry, gravies, and dried or pre-cooked foods are common sources of C. perfringens infections. • C. perfringens infection often occurs when foods are prepared in large quantities and kept warm for a long time before serving. • Outbreaks often happen in institutions, such as hospitals, school cafeterias, prisons, and nursing homes, or at events with catered food. • Often caused by eating temperature abused leftovers such as meat, poultry, or beans. • Control • Proper heating, cooling, and holding of foods

Sources of Microbial Pathogens

• Animals • Raw foods, such as: • meat and poultry • fish • eggs • vegetables • Water • Air and dust • People • Pests • Dirt, garbage and trash

Major spore-formers are:

• Clostridium botulinum • Clostridium perfringens • Bacillus cereus These organisms are present everywhere in environment. Therefore, difficult to control in food processing environment.

• Most effective means of preventing contamination from air are what three things?

• Good sanitation practices • Filtering air entering processing and preparation areas • Appropriate packaging techniques and materials

Pest

• Insects and rodents transfer contaminants from contaminated areas to food. • Are often inhabitants of garbage dumps, sewers, and other areas high in contamination. • May carry contaminants on their bodies as well as in their excrement.

• Raw, untreated sewage can contain organisms excreted by humans and other animals as well as other materials in the environment. • Sewage may contaminate food and equipment through faulty plumbing in the facility. • If raw sewage drains into potable water lines, wells, ponds, rivers, lakes, and oceans, the water and living organisms in these systems (such as seafood) can be contaminated. • To prevent contamination by sewage what three things?

• Large animal production areas, privies, and septic tanks should be well away from wells, streams, and other bodies of water. • Raw sewage should not be applied to fields where fruits and vegetables are grown. • Assure all sewage removal systems within the plant are working properly.

MESOPHILES

• Mesophiles are adapted to moderate temperatures • With optimal growth temperatures ranging from room temperature 20°C to 45°C. • Normal human microbiota (37°C/98.6°F) and many pathogens are mesophiles • Examples: • E. coli, Salmonella spp., and Lactobacillus spp.

Product Packaging

• Packaging should be clean and free of all contaminants such as dust. • Store packaging under conditions that prevent contamination • Packaging should be suitable for its purpose. For example, it should be strong enough to not break under conditions of filling, processing, or storage

PSYCHROPHILES

• Psychrophiles are adapted to VERY cold temperatures • With optimal growth temperatures ranging 0 to 15°C.

• Bacteria are categorized within groups that bear names that indicate their relationships to temperature • These groups are:

• Psychrotrophic (psychro = cold) • Mesophilic ("middle loving") • Thermophilic ("heat loving")

PSYCHROTROPHS

• Psychrotrophs are adapted to cold temperatures • With optimal growth temperatures ranging from 4°C to 25°C. •Examples: •Listeria monocytogenes

Preventing physical hazards involves what two things:

• Regular equipment maintenance and inspection • Detection equipment

• Contamination of equipment occurs both during production and when the equipment is idle. • Product contamination from equipment is reduced by:

• Sanitary design of the equipment • Effective cleaning and sanitizing

THERMOPHILES

• Thermophiles are adapted to hot temperatures • With optimal growth temperatures ranging from 50°C to a maximum of 80°C • Examples • Streptococcus thermophil us, Bacillus spp.

Biological Contaminants (5 examples)

• These are typically microorganisms and include: • Bacteria • Molds • Yeast • Viruses • Protozoa • Methods for control of biological hazards must be used during processing, handling, and storage of food products.

• Food processing plants need an adequate supply of potable water to be used when what three things:

• Water is in contact with food. • Water is an ingredient. • Water is used to make ice and steam.

Clostridium botulinum

• Widely distributed in nature including in soil and water. • Foods often associated with include: • Canned products (proteolytic C. botulinum) • Some refrigerated low-acid products (non-proteolytic C. botulinum) • Causes foodborne intoxication • Produces the deadliest toxin known to humans. • Grows in the absence of oxygen (anaerobic bacteria) • Foods have all the nutrients this microorganism needs to grow. • Spores are everywhere. • Spores are often found on the surface of fruits and vegetables and seafood. • In canned foods, air is excluded so anaerobic conditions allow spores to germinate and become vegetative. • In some oxygen-deprived refrigerated products, non-proteolytic C. botulinum spores can germinate and become vegetative. • During vegetative growth, C. botulinum produces a deadly neurotoxin. • Illness is caused by eating foods containing this toxin. • Characteristics • Toxin produced by vegetative cells can be destroyed by heating to 176oF or higher for 10 minutes • MID = small amount of the toxin • Reducing the pH to 4.6 or less (for both proteolytic and non-proteolytic) • Addition of an acidifier (e.g., vinegar, lactic acid, citric acid) • Fermentation (lactic fermentation) • Commercial sterilization (proteolytic C. botulinum) • Cook the product at 250oF for at least 3 minutes • Pasteurization (non-proteolytic C. botulinum) • Heat the product for a prescribed time in boiling water.

Bacteria require certain nutrients to grow and survive. These include what three things?

• carbohydrates • proteins • small amounts of other materials, such as phosphates, chlorides and calcium

• Non-potable water may be used in a plant for what three things?

• fire control, • refrigeration (cooling towers), • steam production (not used with food), • and other purposes where the water is not in contact with food and so quality doesn't matter.

• There is increased risk of contamination from microorganisms associated with the following products. What are they?

• red meat • poultry • untreated milk • raw eggs • shellfish

• Air may be contaminated by what two things?

• unclean air surrounding the plant, or • improper sanitation practices in the plant.

BENEFICIAL MICROORGANISMS

⚫ Used to produce foods via fermentation: ⚫ brewing, wine making, baking, pickling, fermented products like yogurt ⚫ Help people digest their food ⚫ Some synthesize vitamins ⚫ Break down organic wastes and return them to the soil