Zoonoses/food Hygiene Exam 2

Front 1

Be familiar with the three basic requirements for materials used in food plant construction.

Back 1

1. Easy to clean
2. Impervious to liquids
3. Resistant to wear and corrosion.

Front 2

Identify materials that are acceptable and unacceptable for food processing equipment.

Back 2

Acceptable: any material that is nonabsorbent, nontoxic, odorless, and unaffected by food products and cleaning compounds. Mainly rust-resistant metal and approved plastic materials.
Unacceptable: galvanized metal; enamelware and porcelain; wood; lead, cadmium, and antimony.

Front 3

Understand the function of small tool sanitizers in a meat plant.

Back 3

Small tool sanitizers are containers of water maintained at 180F. The purpose is to minimize cross contamination with infectious agents. Ideally, two tools would be in present, one to use and one in the sanitizer, switching tools between each use. This would allow higher contact time in the water between each use.

Front 4

Be able to identify and describe the major preservation methods and the advantages and limitations of each.

Back 4

1. Thermal processing-cooking to 160F eliminates most microbial toxins. Pasturization inactivates organisms, but requires conjunction with other preservative measures, unless ultra high temperature and aseptic processing is used; standard based on Coxiella burnetii (Q fever).
2. Dehydration-removal of water to below that necessary for microbial growth.
3. Refrigeration/freezing-Below 45F and above freezing=refrigeration, used for short term storage or to delay ripening; freezing can be used for storage typically up to several months.
4. Chemical fermentation/additives-May change flavor, color, texture, odor, or nutrition of the food. May work by binding water, lowering pH.
5. Irradiation-Approved for wheat and flour, vegetables and spices, refrigerated and frozen meats, eggs.

Front 5

Discuss the background of the development of modern poultry inspection.

Back 5

Changes induced by:
1. Military buying "ready to cook" meat.
2. Congressional notice of public interest in whole poultry.
3. Vast increase in the poultry industry starting in the 40's.
4. Death of poultry plant workers from psittacosis.

Front 6

Define "New York dressed" and "ready to cook" poultry.

Back 6

"New York" dressed-feathers and blood removed; legs, head and viscera remain.
Ready to cook-feathers, head, blood, feet, and viscera removed.

Front 7

Define, describe and discuss poultry postmortem disposition.

Back 7

Condemned: Tuberculosis, Marek's disease, Lymphoid leucosis virus, Septicemia or toxemia, late stage or multiple joint synovitis, tumor with metastasis, cadavers, overscald, airsacculitis.
Trimmed: Early stage or single joint synovitis, isolated tumor, bruising.

Front 8

Discuss briefly the basic essentials of modern poultry processing.

Back 8

Live holding and handling area separated from dressing area to reduce dust/feather contamination. Live birds loaded on moving chain, pass through electric water stunning vat; bled out; scalding to loosen feathers, then passed through plucking machines.
Transfer to dressing area; hocks removed and then rehung; circle cut around vent, viscera pulled out and left for inspection; Post mortem inspection (3 seconds); viscera removed and giblets transferred to diff line; lung, kidneys, and reproductive organs reoved by vacuum; transferred to chiller until 40 degrees.

Front 9

Discuss the production and standards of eggs for human consumption.

Back 9

Table eggs are typically infertile. No nutritional difference between fertile and infertile eggs, or eggs with different shell or yolk colors.
Egg maturation: Ovulation occurs 30 minutes after prior egg is laid and egg passes into the infundibulum; chalaza and thick white are formed in the magnum; inner and outer shell membrane are formed in the isthmus; thin white is pumped through the shell membranes in the uterus, and cuticle is applied to the shell; the exterior shell hardens and the air cell forms in the vagina.
The portions of the oviduct cannot be differentiated except by examining the stage of egg formation of an egg currently in the oviduct.

Front 10

Describe the most common reasons for condemnation of eggs.

Back 10

1. Foreign bodies-any foreign particle in the repro tract will be incorporated into the egg.
2. Roundworms-mostly a problem in backyard flocks (exposure to dirt/grass)
3. Multiple yolks-reverse movement of yolk after partial progress down the oviduct.
4. Blood spots-intrafollicular bleeding at the time of ovulation.
5. Checks-incomplete crack with intact inner membrane
6. Cracks
7. Blood rings
8. Fungal growth

Front 11

Describe egg carton labeling, regarding grading and official weights.

Back 11

Egg grading: AA, A and B. Based on how high the yolk stands, visible "step" between thin and thick white, and thin white spreading more than thick when the egg is cracked onto a flat surface. Official USDA grading is voluntary.
Sizing/Weight: Jumbo (30 oz), extra large (27), large (24), medium (21), small (18), peewee (15). Based on minimum net weight per dozen eggs.
Consumer warning: should be labeled as perishable, keep refrigerated.

Front 12

Define the grade standards of milk, and their uses.

Back 12

Grade A raw-cooled to 45F within 2 hours, bacterial count <100,000/mL, SCC <750,000/mL
Grade A pasturized-cooled to 45F within 2 hours, bacteria <20,000/mL, coliforms <10/mL
Manufacturing grade (B)-cooled to 45F within 2 hours, bacteria <100,000/mL, SCC <1,000,000/mL, coliforms/mold/yeast <10/gm, psycotrophic organisms <100/gm.
Grade A raw and pasturized are sold as fluid milk to consumers. Manufacturing grade (B) is used to make cheese, ice cream, powdered milk, etc.

Front 13

Describe the regulatory authority and process that monitors milk quality.

Back 13

FDA is primarily responsible for milk quality. National conference on interstate milk shipments works with FDA. Produces the Grade A Pasteurized Milk Ordinance, updated every 2 years as the gold standard.
States do most inspections and the FDA audits the state programs at regular intervals.

Front 14

Discuss the primary residue challenges faced by the dairy processing industry.

Back 14

Challenges for residue screening include:
1. Not identifying treated cows or not keeping treatment records.
2. Not segregating treated cows.
3. Using common milking equipment for treated and healthy cows.
4. Failure to observe milk discard time indicated on the drug label.

Front 15

Describe the steps in the processing of milk, and the purpose of each step.

Back 15

1. Refrigerated tanker truck picks up milk. A small sample is kept for testing/trace back, the driver smells the milk and check the temp of the bulk tank. Rapid abx test is run on each sample before milk is unloaded at the plant.
2. Filtration/clarification-Filter removes foreign particles. Centrifugal clarification and bactofugation may be done to further remove cells and bacteria from the milk.
3. Separation-centrifugal separation of lighter cream from milk serum (skim milk).
4. Standardization-skim milk and cream are remixed to achieve exact butter fat %.
5. Pasteurization-Regeneration unit passes cool milk and pasteurized milk on opposite sides of metal plates to allow heat transfer. Pasteurization unit raises warmed milk to proper temp. Holding tubes hold milk for proper amount of time.
6. Flow diversion valve-measures temp of milk, will re-run milk if it drops below proper temperature before enough time has passed.
7. Homogenization-mixing of milk to prevent butter fat from settling.
8. Deaeration-expels gas and volatile substances from milk.
9. Refrigeration-temp reduced to <40F as soon as possible. Slows deterioration.

Front 16

List the important pathogens of animals and humans that are killed by pasturization.

Back 16

Brucella spp
Listeria monocytogenes
Salmonella spp
Mycobacterium spp
Campylobacter jejuni
Yersinia enterocolitica
E. coli
Coxiella burnetti (Q fever)

Front 17

Identify the three federal agencies taht have responsibilities in the meat residue program. Define the responsibilites of each agency.

Back 17

FDA-responsible for drug approval. Sets tolerances for acceptable levels of drug residues.
USDA-Monitors tissue samples from slaughtered animals.
EPA-Regulates chemicals applied in a manner that might contaminate the environment (eg. pour-on insecticides)

Front 18

Be familiar withe both monitoring and surveillance phases of the USDA-FSIS meat residue program.

Back 18

Monitoring-carcasses from federally inspected plants are sampled at random throughout the year. Typically 3 or more tissues will be sampled and analyzed for one or more compound. Each species is sampled ~300 times/year. Will detect a 1% incidence, with 95% assurance.
Surveillance-Subjective sampling method implemented when a supplier is responsible for illegal residues or there is some indication that residues may be a problem.

Front 19

Describe the in-plant and on-farm tests that can be used for antibiotic detection in meat.

Back 19

1. Fast antimicrobial screening test-cotton swab of liver or kidney tissue placed on preseeded Bacillus plate, incubated 24 hours. Should not inhibit growth if no abx present.
2. Live Animal Swab Test-same as FAST but uses urine, done pre-slaughter.
3. Sulfa-on-site-screening test for sulfamethazine and other sulfas in swine. Can be done on serum, urine and feed.

Front 20

Describe the criteria for agricultural drug and chemical approval.

Back 20

Must serve a useful purpose in production of feed crops, animals or birds.
Must be shown safe and effective at the proposed dose for the proposed use.
Must not create a residue in the edible tissue at a level harmful to consumers.
Must have a reliable assay method for detecting drug residues in slaughtered animals.
Must be used in a manner that does not contaminate the environment

Front 21

Describe the primary classes of animals found with meat residue violations.

Back 21

1. Cull dairy cattle
2. Bob veal calves (<1 mo of age)
3. Fancy veal calves (1-3 mo of age)
4. Railers (feedlot culls)

Front 22

Identify the most common causes of meat residues and how to avoid them.

Back 22

1. Failure to identify and track treated animals.
2. Failure to keep written records.
3. Failure to know or follow an adequate withdrawal time prior to slaughter.

Front 23

What are the 5 factors required for a foodborne illness to occur?

Back 23

Pathogenic bacteria
Perishable food
Warm temperature
Time for growth/toxin production
Susceptible individual

Front 24

Differentiate between foodborne illness/disease, foodborne intoxication, and foodborne infection.

Back 24

Illness/disease-any illness resulting from the consumption of food.
Intoxication-illness from consumption of food containing a preformed toxin.
Infection-illness from consumption of food containing pathogens that survive the GI tract and other host defenses.

Front 25

What are the two factors that can help differentiate foodborne intoxication from infection?

Back 25

Intoxication-onset is typically <6-8 hours, and does not cause fever.
Infection-onset is typically >8 hours, and is often accompanied by fever.

Front 26

What is the "Danger Zone" temperature that allows for bacterial growth on food?

Back 26

40-140 degrees F.

Front 27

At what water activity are most bacteria unable to grow? What food preservation methods alter water activity?

Back 27

<0.85
Drying, salt curing, and sugar curing.

Front 28

Salmonellosis food poisoning

Back 28

Classification: Foodborne infection
Etiology: Growth of the organism in the food is not necessary, multiples in the GI tract and produces toxin. Requires contamination and mishandling of the food. Does not alter flavor, aroma, appearance, or taste of food.
Symptoms: Onset in 8-72 hours, persists for 4-7 days. Diarrhea, nausea, abdominal pain, chills, fever, and vomiting.
Control: Cook food properly, clean raw food well, avoid cross contamination, pasteurize milk.
Salmonella cycle: animal ingests infected feed, other animals are infected during transport and slaughter, offal from contaminated carcass used in animal feed.

Front 29

Staphylococcal food poisoning

Back 29

Classification: Foodborne intoxication
Etiology: Bacteria must grow in the food, but the enterotoxin is the causative agent of illness. Bacteria could be killed during cooking, and toxin would still cause illness. Does not change the flavor, odor, or appearance of the meat. May come from humans or animals. 6 serological enterotoxins; toxin is heat stable.
Symptoms: Rapid onset (2-4 hours), recovery within 24 hours. Explosive diarrhea, vomiting, abdominal cramps.

Front 30

Clostridium perfringens food poisoning

Back 30

Classification: Infection and intoxication.
Etiology: Organism must grow in the food, and continues to grow in the GI tract; when spores are formed, toxin is released that is responsible for illness. Grows in meat, poultry, soups and gravies. Most problematic in food that is prepared in advance and kept warm but not hot.
Symptoms: Onset 8-22 hours, recovery within 24 hours. Gas, diarrhea, cramps, nausea. Rarely fever and vomiting.

Front 31

Botulism food poisoning

Back 31

Classification: Intoxication
Etiology: Bacteria forms a lethal neurotoxin in non-acidic foods. Types A and B are associated with home canning, E is associated with smoked or raw fish, F also implicated in human disease. Toxin is heat labile, and must be boiled for 30 minutes. Extremely high temperatures, and pressure are necessary to kill the bacterial spores. Will cause food to become malodorous, gassy, or obviously spoiled.
Symptoms: Highly fatal, causes downward progressing flaccid paralysis. Onset in 18-24 hours.
Infant botulism: Infection with multiplication of the organism in the GI tract.

Front 32

Bacillus cereus food poisoning

Back 32

Classification: intoxication
Etiology: Associated with soil, vegetation, and row or cooked foods. Produces 2 toxins.
Symptoms: Toxin 1-watery diarrhea and cramps within 6-15 hours. Toxin 2-nausea/vomiting within 1/2-6 hours.

Front 33

E. coli-EHEC O157:H7

Back 33

Etiology: O157:H7 is most important zoonotic strain because of severity of virulence and clinical disease. Most common reservoir is cattle, but people act as reservoirs as well. Disease is caused by Shiga-like toxins; 2 antigenic types are formed, but cause the same symptoms. Distribution is worldwide and all ages are affected. Period of communicability is 7 days in adults, and up to 3 weeks in children. Incubation takes 3-4 days. Most cases occur in summer and autumn. Highest association is with undercooked hamburger and other ground meats. Transmission is always by fecal-oral contamination.
Clinical signs: Can be asymptomatic. Ranges from mild diarrhea to severe hemorrhagic colitis; may progress from mild to severe; typically lasts 4 days. Other syndromes include: Hemolytic uremic syndrome, and Thrombocytopenic purpura.
Diagnosis: Typically based on clinical signs and consumption of suspected food. Can be cultured from feces within the first week after symptoms start. DNA probes may identify the toxin. Pulse-field gel electrophoresis can identify the strain and is useful in recognizing outbreaks.
Treatment: Most people recover in 5-10 days without antibiotics, and antibiotic use is contraindicated. Supportive care should be given if diarrhea or dehydration is extreme. Further treatment may be required if other syndromes are present.
Control: Good food hygiene and cooking methods! The disease is reportable in people to assist with outbreak investigation. If outbreak is detected, public awareness is raised. Livestock: vaccination is available, proper husbandry, antemortem inspection, hygienic slaughter practices, probiotics, minimize stress; pasteurize or irradiate foods.

Front 34

What organizations are responsible for the inspection of seafood products?

Back 34

USDA-farmed catfish only.
FDA-all others, mostly just involved in reviewing HACCP records, and higher risk products such as shellfish.
NOAA-fee for service inspection agency.

Front 35

Aeromonas infection from pet fish

Back 35

Ubiquitous in aquatic environment. Clinical disease in fish usually secondary to other stressors. Clinical disease in people most commonly due to contamination of a cut or open wound. Causes local wound infection, occasionally gastroenteritis in healthy people; can produce life threatening infections in immunocompromized individuals.

Front 36

Mycobacterium infection from fish

Back 36

"Fish handlers" disease or "Fish tank granulomas".
Typically causes localized, nodular swelling in the skin and joints of the hands/arms. Can cause systemic infection in immunocompromized individuals.

Front 37

Vibrio infection from fish

Back 37

V cholerae, V parahaemolyticus, and V vulnificus are the most common species.
Shed from human feces, but can get into shellfish grown in contaminated water. Causes profound gastroenteritis and dehydration.
V. vulnificus causes necrotizing wounds from skin exposure, and septicemia from ingestion.

Front 38

Clostridium spp infection from fish.

Back 38

C. perfringens-common in gut of fish, causes diarrhea.
C. botulinum-toxin causes paralysis, has been found in canned fish.

Front 39

Hepatitis A from fish.

Back 39

Associated with shellfish grown in water contaminated with human feces, also associated with improper food handling by asymptomatic human carriers. Clinical signs appear 2-6 weeks after exposure; include weakness, fever, malaise, jaundice, abdominal pain, and dark urine.
Vaccine is available.

Front 40

Norwalk virus, Norwalk-like virus, and Norovirus from fish.

Back 40

Similar contamination to Hepatitis A. Associated with cruise ships.
Clinical signs appear in 12-72 hours; include nausea, vomiting, diarrhea and cramps. Hepatitis is rare, but may follow. Resolves in <48 hours.

Front 41

Scombrotoxic fish poisoning

Back 41

Bacterial spoilage causes histamine and histamine breakdown blocking products to build up in the fish. High levels of histamine cause rash, diarrhea, flushing, sweating, headache and vomiting after ingestion. Symptoms are typically mild and resolve in several hours; antihistamines or epinephrine may help.
Prevention lies in proper handling and preventing spoilage.

Front 42

Ciguatera fish poisoning

Back 42

Associated with eating predatory tropical reef fish. Caused by ciguatoxins produced by dinoflagellates, which become concentrated in fish higher in the food chain.
Symptoms typically occur within 30 minutes of ingestion, include nausea, vomiting, diarrhea, cramps, sweating, headache, muscle ache, pins-and-needles, weakness, itching, and dizziness.
Ciguatera is rarely fatal, and symptoms clear within 1-4 weeks.
Can only be prevented by avoiding eating these types of fish.

Front 43

Paralytic shellfish poisoning

Back 43

Associated with "red tide" dinoflagellates-Pacific states and New England. Toxin accumulates in shellfish.
Symptoms begin 15 min to 10 hours after ingestion. Typically mild; numbness or tingling of the face, arms, and legs, headache, dizziness, nausea, and muscular incoordination.
In severe cases, muscle paralysis and respiratory failure can occur.

Front 44

Neurotoxic shellfish poisoning

Back 44

Caused by dinoflagellate toxin in the Gulf of Mexico and the Atlantic southern states.
Symptoms appear 1-3 hours after ingestion; Including numbness, tingling in the mouth, arms, and legs, incoordination, and GI upset. Recovery occurs in 2-3 days.

Front 45

Amnesic shellfish poisoning

Back 45

Caused by the toxin from Nitzchia pungens (diatom), on the west coast of the US.
Symptoms begin within 24 hours. Primarily GI distress, but can include dizziness, headache, disorientation, and permanent short-term memory loss.

Front 46

Diarrhetic shellfish poisoning

Back 46

Triggered by okadaic acid. Causes nausea and diarrhea, often confused with bacterial contamination. Recovery in 1-3 days.
Occurs in Europe.

Front 47

Methylmercury fish contamination

Back 47

Elemental mercury, primarily from industrial sources, is deposited in water sources where it is converted to methylmercury. Methylmercury is then bioaccumulated in the aquatic food chain. Toxic levels are typically associated with larger, predatory fish.
Symptoms include neurologic, cardiac, immune, endocrine, and behavioral problems. Many symptoms cease after the mercury source is removed, but long term exposure can also lead to renal failure. Also has teratogenic effects on fetal brain development.