Lecture 7: Food Safety Intro (Exam 2) Flashcards
What is food safety
The science of protecting our food supply from contamination by disease-causing bacteria, viruses, chemicals, & other threats to health
What are the four major trends creating food safety challenges
- A substantial & increasing portion of the US food supply is imported
- Consumers are eating more raw & min processed foods
- Increased @ risk populations
- Consolidation of the industry leading to amplification of food risks
How many agencies did the president assign to safeguard the food supply
~12
Who coordinates food recalls
- FDA
- USDA
- DHS
*CDC - The states
What are the components of the food safety triad
- Food supply chain
- Consumer
- Regulator
What did thomas malthus determine (the Malthusian growth potential)
- The population when unchecked increases @ a geometrical ratio
- Subsistence increases only in an arithmetical ratio
- A slight acquaintance w/ # will show the immensity of the first power in comparison w/ the second
- Humans are producing @ such a fast rate that we will eventually run out of food and die
What are the poor assumptions mad be Malthus
- he didn’t foresee to what degree technology would increase food prod
- He assumed humans have no control over their repro behavior
- He equated famine w/ a lack of food rather than an unequal distribution of ava food
What are the growth req of microorganisms
- Food - some source of E
- Acidity - best growth btw/ 4.6 & 7.5
- Temperature - the danger zone is 40 to 140 degrees F
- Time - 4 hours is considered max
- Oxygen - req by most pathogens
- Moisture - safer foods have a aw < 0.85
(FATTOM)
T/F: Nearly all foods are processed to some degree
True
What are examples of min processed
- Washed
- Peeled
- Sliced
- Juiced
- Frozen
- Dried
- Fermented
- Pasteurized
Examples of highly processed
- Baked
- Fried
- Smoked
- Toasted
- Puffed
- Shredded
- Flavored
- Colored
- Fortified (vitamins)
Why are foods processed
- Preservation
- Food safety
- Variety
- Convenience
- Nutritional enhancement
- Increase marketability
- Organoleptic properties
What are the method s of food preservation intended to accomplish
- Reduce existing pathogen load
- Render food envi inhospitable to microorganisms by ensuring one of the growth req doesn’t occur
- Provide a physical barrier to contamination/inoculation
Define food preservation
The process of treating & handling food to stop or greatly slow down spoilage in order to prevent foodborne illness & extend its shelf life
What are common food preservation methods
Describe refrigeration/freezing
- The most common preservation method
- Slows microbial growth & enzymatic action
- Fosters longer life for transportation & storage
- Storage of strategic food stocks for many nations
What is Irradiation
- Cold pasteurization
- Exposure to low dose ionizing radiation (cobalt 60 or CS137
- Kills nearly all surface pathogens (may even achieve sterilization)
- Food does not become radioactive & remains wholesome
- Endorsed by WHO & FAO
- Approved by the FDA
- Not suitable for dairy products & some fruits
- Since 1986 all irradiated food must display the radura
- Ex - wheat, potatoes, flour, & spices
Describe freeze-drying
- Combo of freezing & lowering ambient pressure which causes free water to sublimate (product typically has 1 to 4% water content)
- Causes less damage than other drying methods
- Also used for drugs (like vax)
- Does not cause shrinkage but does reduce weight
How does pickling preserves food
Preserves food in an edible antimicrobial liquid (lowers water activity & pH)
Describe chemical pickling
- Salt brine, vinegar, alcohol, & vegetable oil
- Used in food like cucumbers, peppers, corned beef, herring, eggs, & olives
Describe fermentation pickling
- The food itself produces the preservation agent
- Facilitated by Lactobacillus organims
- Ex - sauerkraut & Kimchi
Elaborate on fermentation
- One of the oldest preservation tech
- Beneficial microorganisms complete w/ pathogens
- Converts starch (sugars) to alcohol which lowers the pH (doesn’t primarily reduce water ava)
- Produces vitamins (Vit)
- Ex - beer, sour cream, kefir, kimchi, & yogurt
What is pulsed electric field electroporation
- Treating food w/ brief pulses of strong electric field
- Cell membrane pores are enlarged (killing cells)
- Most common for fruit juices
What is biopreservation
- The use of natural or controlled microflora to preserve food & extend its shelf life (good microorganisms compete w/ pathogens)
- Lactobacillus is most commonly used (produces natural preservatives like lactic acid, acetic acid, & nisin)
- Ex - veggies, cereals, & meats
- Most have broad spectrum action but some can specifically target certain pathogens
Describe salt or sugar curing
- Both result in lowered water activity
- Additionally osmotic pressure lyses cell membranes
- Ex - Salted meat, fruit in honey or heavy syrup, & salted anchovies
What is pasteurization
- Preservation tech for liquid food
- Was originally for wine
- Kills 99.999% of microorganisms in milk but is not complete sterilization
Describe high temp short time pasteurization (HTST)
- 161 F for 15 sec
- 145 F for 30 min
Describe Ultra high temp pasteurization (UHT)
275 F for 2 secs
Describe Extended shelf life pasteurization (ESL)
Lower temps than UHT but adds a filtration step
What is the shelf life for HTST & UHT
- HTST: 60 to 90 D
- UHT: 180 D
What did pasteurization originally target
Mycobacterium bovis which is a causative agent of zoonotic tuberculosis
What pathogen was pasteurization later adjusted to inactivate
Coxiella burnetii (Q fever) which is the most heat resistant organims currently recognized in milk
Describe the pasteurized milk ordinance (PMO)
- Dev in 1924 by the US public
- Now adopted as the national standard for milk production, processing, & packaging
Describe smoking
- Wood smoke deposits natural preservatives on meats & fish (syringol, gauiacol, & catechol)
- Physically dries the surface of the food item
Describe antimicrobials food additives & list the most common
- Inhibit the growth of microorganisms
- Calcium
- Propionate
- Na nitrate
- Na nitrite
- Sulfites
- Disodium EDTA
Describe antioxidants food additives & list the most common
- Inhibit the oxidation (spoilage) of food
- Butylated hydroxyanisole (BHA)
- Butylated hydroxytoluene (BHT)
- Ascorbic acid (C)
- Tocopherol (E)
Elaborate on modified atmosphere
- Storing or packing foods that spoil easily or age quickly
- Reduces oxygen & replaces it w/ carbon dioxide or nitrogen
- Slows aging & prevents insect infestation
- Eastern Wa has MA space for > 100 million boxes of apples
- MA grains can be stored for 4 to 5 Y
What is hurdle tech
- Controlling or eliminating foodborne pathogens by the application of more than one approach
- “more” hurdles for the pathogen to overcome
- Define in 2000
- Approaches are specifically selected to preserve organoleptic qualities like appearance, taste, smell, & texture
What are the vets roles in meat production
- Antemortem - animal welfare, disease triage, & dx testing prn
- Postmortem - carcass inspection & tissue residue determination
What are vets roles in herd health programs
- Disease tx & prevention
- Husbandry/handling issues
- Envi control/modification
- Repro efficiency
- Vax regimens
- Nutrition
- Stress reduction
- Commodity protocols
- Biosecurity & biocontainment plans
What are the general roles of vets
- Appropriate/judicious use of antimicrobials
- Disease surveillance programs
- Epidemic/outbreak investigation
- Collaboration w/ other health professionals
- Import/export certifications
- Health department involvement/leadership
- Public health (risk) communication
- Food supply following disasters
- Food production research
Describe the animal medicinal drug use clarification act of 1994 (AMDUCA)
Allows vets to prescribe extra label drugs to ALL animals if the health of the animal is threatend & suffering/death may result if the treatment is not provided
T/F: prior to AMDUCA extra label drugs were legal
False they were illegal & very few drugs were labeled for use in animals esp food animals
What are the req for extra label use
- Careful dx must be est
- Ensure that no approved animal drug exists for that condition
- Est a substantially extended scientifically derived withdrawal period
Can a drug labeled for human be admin to animals even if an animal labeled drug exists
Yes if they are non-food-producing animals
What happened in 1996
Congress passed the animal drug ava act (ADAA)
What is the ADAA
- New regulatory category for restricted feed use drugs
- The vet feed directive (VFD)
- Before this there was only OTC & prescription
- Eliminates the sub therapeutic use of medical impt drugs in agri
What is the primary purpose of the VFD legislation
- Places effective controls on certain antimicrobials
- Limits the potential for dev of antimicrobial resistance
How many drugs are approved for medicated feeds
17
