Food Science #2 - Midterm Flashcards
What is Foodborne Disease?
- Any illness resulting from the consumption of food contamination by bacteria, viruses, parasites, chemicals, or toxins;
- Not always bacteria, toxin caused from bacteria;
- TOXIN creates illness quickly;
- BACTERIA/VIRUSES take longer to develop in GI tract
What is Food Safety?
The scientific discipline describing handling, prep, and storage of foods in ways that prevent food borne illness
US Foodborne Illness Stats
1999: -76 million illnesses; -325,000 hospitalizations; -5,000 deaths; 2011: -48 million illnesses; -128,000 hospitalizations; -3,000 deaths
BACTERIA Foodborne Illnesses
- Illness = 39%;
- Hospitalizations = 64%;
- Deaths = 64% (MOST DEATHS)
PARASITE Foodborne Illness
- Illness = 2%;
- Hospitalizations = 9%;
- Death = 25%
VIRUS Foodborne Illness
- Illness = 59% (MOST ILLNESS);
- Hospitalizations = 27%;
- Deaths = 12%
Which bacteria causes the most foodborne illnesses?
- Norovirus;
- Salmonella;
- Campylobacter (Poultry)
Which bacteria causes the most hospitalizations?
- Salmonella;
- Norovirus;
- Campylobacter
Which bacteria causes the most DEATHS?
- Salmonella;
- Toxoplasma gondii;
- Listeria
Which bacteria causes the highest % of foodborne illnesses?
- Listeria = 99%
- Salmonella = 94%;
- Campylobacter = 88%
What are the categorizations of food?
- Aquatic animals;
- Land animals;
- Plants
Aquatic Animals
- Fish;
2. Shellfish (crustaceans/mollusks)
Land Animals
- Dairy;
- Eggs;
- Meat-Poultry (beef, game, pork, poultry)
Plant Foods
- Grains-beans;
- Oils-sugars;
- Produce (Fruits/nuts, vegetables)
What is the Food Production Chain?
- Production;
- Processing;
- Distribution;
- Restaurant/Retail;
- Prep (home/restaurant);
- Consumption
Risks at PRODUCTION
- Fecal - sewage;
- Birds, wild pigs, oyters – animals;
- Water;
- People
Risks at PROCESSING
- Improper sanitation;
- Cross-contamination;
- Temp. abuse;
- People;
- Improper cooking
Risks at DISTRIBUTION
- Temp. abuse;
- Contamination of equipment;
EX: Rat outbreak - 224,000
Risk at RETAIL
- Humans;
- Cross-contamination;
- Improper cooking temp.
Risks at PREPARATION
- People;
- Cross-contamination;
- Improper cooking temp;
- Temp. abuse
What is the CDC?
- Governmental safety programs;
- Primary public health agency;
- Conducts primary national surveillance;
- Conducts outbreak investiagations
What are the primary regulatory agencies?
- FDA = ALL FOODs EXCEPT red meat, poultry, bottled water;
- USDA/FSIS = red meat, poultry, and processed eggs - regular inspections;
- EPA - drinking water
What are the FDA food safety activities?
- Safety programs;
- Reportable Food Registery (RFR);
- Food Protection Plan 2007 (fact sheet);
- FDA Food Safety Modernization Act 2011
What is the Reportable Food Registry?
September 2009;
- An electronic portal for industry to report (within 24 hours) when there is a reasonable probability that an article of food ail cause health consequences or death;
- Report method to the FDA
What are the classes of health consequences reported to the RFR?
- Class 1 = Can cause DEATH; food borne pathogens;
- Class 2 = Might cause sickness;
- Class 3 = Not a serious consequence
What are the components of the Food Protection Plan 2007 fact sheet?
- Prevention;
- Intervention;
- Response
Food Protection Plan - PREVENTION
- Increase industry responsibility;
- Identify foods risks;
- Understands the use of mitigation measures
Food Protection Plan - INTERVENTION
- Focus inspection and sampling risks;
- Improve the detection of food systems that indicate contamination;
- Prevent food from going to market
Food Protection Plan - RESPONSE
- Improve immediate response (RFR);
- Improve communication with the public
Who is covered under the Food Safety Modernization Act (FSMA) of 2011?
-Facilities that manufacture, process, pack or hold human foods
What is included in a Written Food Safety Plan under the FSMA?
- Hazard analysis;
- Preventive controls;
- Monitoring;
- Corrective action;
- Verification;
- Record Keeping
Hazard Analysis
- Looks at food products and identify what the hazards are;
- Identifies and evaluators hazards for foods
Preventive Controls
-Identified and implemented to provide assurance that the hazards will be minimized or prevented
Monitoring
-Procedures to provide assurance that preventative controls are consistently performed and records to document the monitoring
Corrective Action
-Would be used if preventative controls are not properly implemented
Verification
- Reevaluate food safety plan every 3 years;
- Verify preventative controls are effective
Record Keeping
-Keeps records of everything
What is included in Good Agricultural Practices for PRODUCE Safety?
- Soil
- Water
- Hands
- Surfaces
Produce Safety - SOIL
- Possible source of pathogens if you use MANURE;
- Using mulch and compost will help to avoid
Produce Safety - WATER
- The source of water depends if it has lots of microbes in it;
- Ground and well water has fewer
Produce Safety - HANDS
-Washed regularly, clean and properly stocked restrooms and hand washing facilities
Produce Safety - SURFACES
- Cleaning/sanitizing;
- Make sure you don’t buy produce with cuts and bruises
Developing a Food Safety Plan for Produce Safety (5 steps)
- LIST steps − planning to packaging;
- IDENTIFY areas where safety can be affected;
- MEASURE and MONITOR the risk;
- MODIFY practices to reduce risks;
- DOCUMENT all steps and the changes
What are included in FDA Education Campaigns?
- Food — Resources for Public — Health educators;
- Educational campaigns;
- FDA Food Safety Hotline
What are some food safety & nutrition education campaign?
- Vibrio vulnificus kit;
- Kids and teens
- Pregnant women;
- Hispanic community;
- Fight BAC! Campaigns
What is included in the USDA?
- Food Safety Inspection Service (FSIS);
- Food Safety education (by subject);
- USDA’s Meat and Poultry Hotline
What is HACCP?
- Hazard Analysis and Critical Control Points;
- A preventative food safety management system;
- Identifies specific hazards and determines where chemical, biological, physical, etc.;
- Identifies preventative measures for this control to ensure the safety of food
How is HACCP a dynamic process control system?
- Hazards = physical, chemical, biological (toxins);
- Steps from RAW material to FINISHED products;
- Need to know if raw materials are safe!;
- Science-based control method
What is the history of HACCP?
1959 - NASA in space;
1971- National Conference on Food Protection;
1985 - National Academy of Science (HACCP for all reg. agencies);
1988 - National Committee of Microbiological Criteria for Foods (NACMCF) - drafted a guide;
1992/94 - General Accounting Office
HACCP in US Food Timeline
1996 - USDA/FSIS mandates use in meat/poultry (CFR Title 9) = FIRST use in foods;
1997 - FDA mandates use in seafood processing (CFR Title 21);
1998 - FDA mandates use in fruit and veggie juice (CFR Title 21)
What are the 7 principles of HACCP?
- Conduct hazard analysis and identify preventative measures;
- Identify critical control points (CCPs);
- Establish critical limits (CLs);
- Establish monitoring procedures for each CCP;
- Establish corrective actions;
- Establish verification procedures;
- Establish record-keeping and documentation procedures
HACCP Step 1: Hazard Analysis
- Identify where the hazards are;
- Create preventatives
HACCP Step 2: CCPs
-CCPs = a step during processing at which CONTROL can be applied and is essential to prevent/eliminate food safety hazards!;
-Where are the CCPs during processing;
-At what step do we have to monitor them?;
EX: Cooking = time and temp to maintain safety
HACCP Step 3: Critical Limits (CLs)
-CL = a max or min (value) at a CCP, which can be monitored and separated from unacceptable;
EX: Hamburger meat has to be at 160F - make sure you have a temp and sanitizing acceptability
HACCP Step 4: Monitoring CCPs
-Sanitation = microtesting
HACCP Step 5: Corrective Action
- If dirty, resanitize it;
- Must verify safe before being able to send out
HACCP Step 6: Verification Procedures
- Obtain scientific evidence that it is working!;
- Validation and verification of procedures
What is Validation?
-Validating = obtaining evidence that the elements of a HACCP plan are effective;
EX: Microbiological examination of equipment surfaces before and after sanitation; BEFORE to know the limit of microorganisms, then AFTER will have critical limit after sanitizing
What is Verification?
-Verification = the application of methods, procedures, tests and other evaluations, in addition to monitoring to determine compliance with a HACCP plan;
EX: Microbe testing of chicken burger to make sure it is free of campylobacter (on surface of chicken)
HACCP Step 7: Record-Keeping and Documentation
-Keep records of everything in a book to give when someone comes and checks (inspections)
What is HACCP NOT?
- NOT a “zero-risk” system, it minimizes risks;
- NOT a “stand-alone” system. Sometimes uses GMP (good manufacturing practices) and others for total insurance of food safety;
- *HACCP is SPECIFIC, while GMP and other are general
What are some consumer foods safety awareness programs?
- Fight Bac! = mostly for kids;
- Be Food Safe from USDA and partnership for Food Safety Education = adults
What are the steps to Consumer Safety?
- Clean/Wash Hands and Surfaces Often;
- Separate, Don’t Cross-Contaminate;
- Chill/Refrigerate Properly and Promptly;
- Cook to Proper Temps
Consumer Safety Step 2: Don’t Cross Contaminate
- Separate raw meat, poultry, and seafood from others;
- Shopping cart and bag;
- Refrigerator;
- On cutting board;
- On plates
Consumer Safety Step 1: Clean Hands and Surfaces
- Wash hands in sopay water for 20 secs;
- Wash cutting boards, utensils and counters after seafood;
- Wash cutting boards in hot soapy water;
- Use paper towels to wipe surfaces
Consumer Safety Step 3: Chill/Refrigeration
- Refrigerate 40F or below;
- Freeze 0F or below;
1. Use to keep it cool;
2. The chill factor;
3. The thaw law;
4. Divide and conquer
Chill Factor
- Fridge within 2 hours;
- Within 1 hour if temp outside is above 90 degrees
Thaw Law
- Thaw in fridge;
- Use cold or luke warm water;
- Change water every 30 mins;
- Microwave
Consumer Safety Step 4: Cook to Proper Temp
- Use a food thermometer to cook evenly;
2. Cook evenly with NO cold spots
How do consumers view food safety?
- 82% say food safety is “very important”;
- 97% think home prep is important to safety;
- 62% say restaurant accommodations for “doggy bag” storage would help
What are the potential sources for Salmonella and Campylobacter?
- Meat and Dairy!
- Poultry, meat, eggs, unpastuerized milk, raw produce
What are the potential sources for Listeria?
- Processed meats and cheese!
- Raw milk, soft cheese, lunch meat, hot dogs, raw produce
What are the potential sources for E. Coli?
- Raw products - especially animal products!
- Raw/undercooked meat;
- Raw produce;
- Raw milk
How does food borne illness occur?
- Contaminated foods;
2. Microbes overtake body’s defense (immune system)
What are the primary symptoms of food borne illness?
- Nausea;
- Vomiting;
(N & V typically don’t occur together); - Abdominal cramps;
- Diarrhea
(Cramps and diarrhea usually together)
What groups are at INCREASED risk of food borne illness?
- Young children;
- Pregnant women;
- Elderly;
- People with auto-immune dz;
- Decreased stomach acidity;
- Liver damage;
- Taking steroids (take down bodies immune system);
- Viral infections;
- Malnutrition/malnourished
What risks can YOU control at home?
- Improper refrigeration/storage;
- Poor personal hygiene;
- Prevent cross-contaminationl
- Don’t use possibly contaminated food sources;
- Under cooking;
- Always follow all time and temp precautions
How important is effective hand washing to prevention of food borne illness?
-Effective hand washing may eliminate HALF of all cases of food borne illness
Effective Hand Washing
- Use warm soapy water;
- Wash front to back;
- Up to wrist;
- Under nails;
- 20 secs in length (Happy B-day song X2);
- Rinse and dry with paper towel, clean cloth, or air dry
Was your hands BEFORE…
- Preparing foods;
- Eating meals;
- Feeding children
Wash your hands AFTER…
- Handling raw foods (any - meats, eggs, fresh fruit, veggies);
- Switching food prep tasks;
- Using the restroom;
- Changing a diaper;
- Coughing or sneezing;
- Handling garbage or dirty dish;
- Touching a cigarette;
- Using the phone;
- Playing with a pet;
- Touch a cut or sore
How do you keep kitchen surfaces safe?
- Always use hot, soapy water;
- Wash dish cloths and towels in washing machine on HOT;
- Sanitize sponges in bleach solution;
- Replace sponges frequently;
- DO NOT use dish towels for multiple jobs
What is Cross-Contamination?
-When microbes from one food or surface are transmitted to another food item
How do you prevent cross-contamination?
- Store raw meat on BOTTOM of fridge;
- Wash all produce;
- Store washed produce in clean containers;
- Wash cutting board b/w uses or separate per food type;
- Use one utensil to taste and another to stir;
- Use clean scissors to open bags;
- Wear disposable gloves if ou have a cute or sore on hand
How do you keep cutting boards safe to prevent food borne illness?
- Use 2 cutting boards — 1 for raw; 1 for ready-to-eat foods;
- Wash boards thoroughly in hot soapy water or place in dish water;
- Rinse thoroughly with soapy water;
- Cutting raw meat, use some sanitizers;
- Discard boards when cracked, crevices, or scars
How do you ensure proper cooking temps?
- Use a thermometer;
- Wash thermometer in hot soapy water;
- Cook to proper temp.
How do you take temp of red meat, roast, steak, chops, poultry pieces?
Insert into thickest part of meat, away from bone, fat and gristle
How do you take temp of whole bird, poultry?
Insert into inner thigh area, near breast, not touching bird
How do you take temp of ground meat, poultry?
Insert into thicket area of meatloaf or thick patty , reaching very center with stem;
For thin patties, insert sideways into center
How do you take temp of egg dishes, casseroles?
Insert to center of thickest area of dish
How do you take temp of fish?
Fish is done when opaque and flakes easily with a fork
Food Safety during SHOPPING
- Purchase refrigerated food/frozen items after selecting non-perishable;
- Never choose meat or poultry in packaging that is torn of leaking;
- Do not buy food part “sell-by” date or other expiration date
Food Safety with STORAGE
- Refrigerate 2hours (if temp above 90F, fridge in 1hr);
- Check temp of fridge (40F and below) and freezer (0 and below);
- Meat and poultry wrapped securely to maintain quality and prevent meat juices from getting on other foods;
- Cook/freeze fresh poultry, fish, ground meats - within 2 days; Beef, lamb, veal, or pork in 3-5 days;
- Freezing meat and poultry in original packing wrap again in foil or plastic meath for freezer;
- Canned - low acid foods for 2-5 years;
- High acid foods store unopened 12-18 months
Food Safety with THAWING
- Refrigerator =
- Cold water =
- Microwave =
Proper Cooking Temp for Beef, Pork, Veal, & Lamb
- Ground = 160F;
- Steak, Chops, and Roasts = 145F, 3mins to rest
Proper Cooking Temp for Chicken & Turkey
-ALL types = 165F
Proper Cooking Temp for Eggs
-Any type = 160F
Proper Cooking Temp for Fish and Shellfish
-Any type = 145F
Proper Cooking Temp for Leftovers
-Any type = 165F
Proper Cooking Temp for Ham
- Fresh or smoked (uncooked) = 145F, 3 mins to rest;
- Fully cooked ham (to reheat) = 140F from USDA plants; 165F all others
At what temps should food SERVED/HELD?
- HOT = held at 140F or warmer;
- COLD = held at 40F or colder;
- Buffet hot foods — chafing dishes, slow cookers, warming trays;
- Buffet cold foods — nesting dishes with ice, small serving trays and replace often;
- Use a food thermometer;
- Perishable not left out more than 2hrs at room temp (1hr when temp above 90F)
How should LEFTOVERS be handled to maintain safety?
- Discard any food left out at room temp more than 2hrs (1hr over 90F);
- Place food into shallow containers and immediately put in fridge for quick cooling;
- Use most within 3-4 days;
- Reheat ALL leftovers to 165F
How do you properly REFREEZE?
- Meat and poultry defrosted in the fridge maybe refrozen before or after cooking;
- Thawed by OTHER methods, COOK before refreezing
How are foods properly stored COLD?
- Times keep refrigerated (at 40F) from spoiling or becoming dangerous to eat;
- FREEZING at 0F or below (NOT 32F) keeps foods safe indefinitely, recommended freezer storage time are for QUALITY only;
- Use appliance thermometers to monitor storage temps
What is Epidemiology?
The study of the causes, distribution, and control of disease in population;
-Is it from food??
What TOOLS are used in epidemiology of food borne illness?
- Disease surveillance - 5 years;
- Molecular finger printing (typing);
- Antibiotic resistance monitoring;
- “Case-Control Study”
What is CHANGING Epidemiology of Foodborne Disease?
- Emerging Foodborne Pathogens;
- Evolving Foodborne Pathogens;
- Global Dissemination of Foodborne Pathogens in Pandemic Form;
- Increasing Antimicrobial Resistance;
- A “new scenario” outbreak
What are the EMERGING (new vs. old ) food borne pathogens?
NEW =
1.Clostridium difficult —meds killing bodies natural bacteria;
2. Hepatitis E (zoonomic diseases between human and animals) and Hepatitis C - Pork (fecal), pork liver and brains;
OLD =
1. Listeria monocytogenes — RTE meat products
What are EVOLVING (old pathogens) food borne pathogens?
- Increasing occurrence of known food borne pathogens;
2. Associated with new food vehicles (EX: Listeria in cantaloupe)
Example of Global Dissemination of Foodborne Pathogens in PANDEMIC Form?
**Multiple Continents or World Wide!
EX: Salmonella enterica Typhimurien DT104
Example of Increasing Antimicrobial Resistance
EX: Salmonella enterica Typhimurien DT104
What is a “new scenario” outbreak?
- Multistate outbreaks;
- 2 or more people must get sick
What FACTORS Contribute to the Changing Epidemiology of Foodborne Disease?
- Changing demographic characteristics;
- Changes in human behavior;
- Changes in food production;
- Changes in travel and commerce;
- Microbial adaptation
What are the 1. Changing demographics characteristics?
- Advanced ages;
- Immunocompromised people;
- Chronic disease
What are 2. Changes in human behavior?
- Eating out;
- Putting food prep in other hands;
- Fresh fruits and veggies
What are 3. Changes in food production industry?
- Large centralized food processors,
- Mass distribution
What are 4. Changes in travel and commerce?
- Shift towards global economy;
- Increased importation of food
What is 5. Microbial Adaptation?
- Natural selection, adapt to ecological environment;
- Antimicrobial resistance in response to selection pressure from use of antimicrobials in humans and animals, and in agricultural settings
What changes have taken places in surveillance strategies?
- 3 Agencies;
1. FoodNet, 1996;
2. PulseNet, 1997;
3. NARMS, 1996
What is FoodNet 1996?
Foodborne Disease Active Surveillance Network
What is PulseNet 1997?
- Connects cases of food borne illnesses to potential outbreaks using DNA fingerprinting;
- Take samples from people who have been affected
What is NARMS 1996?
- National Antimicrobial Resistance Monitoring System;
- Do surveys on diseases
What agencies are involved in FOODNET?
- Collaborative effort b/w CDC, USDA, and FDA, and 10 Emerging Infectious Program Sites;
- 1996 = Officially launched;
- 2010 = Covered population 46 million, 15% of US population;
- Laboratory-based ACTIVE surveillance at over 650 clinical labs
What are the FoodNet States?
- California;
- Colorado;
- Connecticut;
- Georgia;
- Maryland;
- Minnesota;
- New Mexico;
- New York;
- Oregon;
- Tennessee
What are the objectives of FoodNet?
- Determine the burden of food borne illness in the US;
- Monitor the trends in the burden of specific food borne illnesses over time to see if its decreasing or increasing;
- Attribute the burden of food borne illness to specific foods and settings;
- Develop and assess interventions to reduce the burden of food borne illness
What is the Burdens of Illness Pyramid?
-Model for understanding foodborne disease reporting
What are the levels of the Pyramid?
- Population Survey = Exposure in general population; Persons become ill;
- Physician Survey = Person seeks care; Specimen Obtained;
- Laboratory Survey = Lab tests for organisms; Lab confirmed case;
- Surveillance = Reported to Health Dept./CDC
What are the FoodNet Target Organisms?
- Campylobacter (poultry);
- Cryptosporidium (product: water contamination;
- Cyclospora (produce, fecal contamination);
- E. Coli O157:H7 (cattle, ground beef);
- STEC non-O157/Shiga Toxin E. Coli;
- Listeria Monocytogenes;
- Salmonella;
- Vibrio (seafood);
- Yersinia entercolititca (undercooked pork)
What disease agents have increased since the 2010 progress report for food safety?
- Campylobacter = 13%;
2. Vibrio = 75%
What PulseNet?
- Compares the DNA finger prints of bacteria from patients and food to find of disease that might represent unrecognized outbreaks;
- CDC sends them samples;
- Almost EVERY state participates
What are the PulseNet Pathogens of interest?
- Campylobacter;
- E. Coli;
- Listeria monocytogenes;
- Salmonella;
- Shigella;
- Vibrio
What is the structure of food borne pathogens?
- Have FLAGELLA to more through the our intestines;
- Use the CAPSUL to attach;
- Use the PILUS to further attache
What are the food borne illness classification?
- Foodborne Infections;
- Foodborne Intoxication;
- Fiidborne toxico-infections
What are Foodborne INFECTIONS?
-Ingestion of a microorganism in food that establishes in the human host;
-Usually has ways to attach to intestine;
-Occurs in 12-72 hours;
-If you’re NOT in good health you get sick factors;
EX: Salmonella, Campylobacter
What are Foodborne INTOXICATION?
-Grows and releases toxins in the food prior to consumption;
-Self-limiting;
-Get sick within 2-3 hours;
EX: Staph aureaus, Clostridium botulinum
What are Foodborne Toxico-Infections?
-Microbe ingested causes illnesses by producing toxin while growing in human intestinal tract;
-Can colonize and cause infection;
-Get sick in 12-72 hours;
EX: Shiga toxin-producing E. Coli, Vibrio, and Cholerae
What do we need to know about Foodborne Pathogens in Food?
- Unique characteristics;
- Reservoir;
- Transmission vehicle (water, human, animal);
- Symptoms of disease;
- Major outbreaks;
- Control methods
What is Salmonella?
- One of the leading pathogens/bacteria - naturally found on chicken and can be destroyed by cooking;
- Family= Enterobacteriaceae;
- Genus = Salmonella;
- Species = Enterica, bongori;
- > 2500 serotypes; S. enterica serovar Typhinimrium, S. enteritidis;
- Gram-negative, rod-shaped;
- Usually motile, pertricious (all over) flagella;
- Optimum growth temp 37C (body temp);
- Facultative anaerobic (no oxygen)
What is Gram-Negative?
-Thinner amount of peptadoglycan on the surface
What are the annual estimates of Salmonella?
- 1 million cases;
- 19,00 hospitalizations;
- 378 deaths;
- Estimated cost per case = $9000;
- *Leading cause of food borne illness and death!!
What are the leading Salmonella serotypes?
- Enteritidis = 22%;
- Newport = 14%;
- Tphimurium = `3%
What is the Salmonella-infectious dose?
- Generally 10^6 of cells;
- Some serotypes can be as low as 15-20cells
What is are the symptoms of of Human Salmonellosis?
- Gastroenteritis = abdominal pain, diarrhea, fever, nausea, vomiting, headache;
2 Systemic infection (all over the body) = arthritis, meningitis, bacteremia
What is the Treatment for Human Salmonellosis?
- Self-limiting, recover after 4-7 days with no antibiotics in HEALTHY individuals;
- Antibiotic lifesaving = Ciproflocicin and Ceftriaxone
What FOODS are reservoirs for Salmonella?
- Food animals (intestinal tracts of healthy animals) - cattle, chicken, turkey, pigs;
- Pet animals - reptiles, turtles
How is Salmonella transmitted?
- Animal feces (fecal-oral route);
2. Meat, poultry, eggs, milk, dairy (anything raw)
How can Salmonella be controlled?
- Reduced fecal contamination;
- Pasteurize eggs, milk, dairy;
- Competitive exclusion
What is Competitive Exclusion?
- Take feces from Salmonella-FREE birds and provide them to chicks through drinking water, spray inoculation;
- The competitive excision microflora establishes within hours and persists throughout life
What was the large Salmonella outbreak of 1985?
- Pasteurized milk mixed with raw milk, single plant (Illinois);
- S. enterica Typhinurium;
- 20,000 persons, 7 deaths
What was the large Salmonella outbreak of 1994?
- Ice cream mix (pasteurized) re-contaminated in tank truck used previously to ship liquid eggs;
- S. enterica Enteritidis;
- 200,000 persons in 21 states
