Chapter 13Chapter 13

Safety of Safety of Food and Food and

WaterWater

Foodborne IllnessFoodborne Illness

Greatest risk from viral and bacterial Greatest risk from viral and bacterial contamination: contamination: – e.g. e.g. E. coli: E. coli: O157:H7 (199 peo. 26 states fresh O157:H7 (199 peo. 26 states fresh

spinach (102 hospitalized, 31 kidney failure)spinach (102 hospitalized, 31 kidney failure)

Major cause of diarrheaMajor cause of diarrhea

Usually results from unsafe food handling Usually results from unsafe food handling in the in the HOMEHOME

Shiga Toxin

E. coli: E. coli: O157:H7O157:H7

Most Susceptible to Most Susceptible to Foodborne IllnessFoodborne Illness

Infants and childrenInfants and children Older adultsOlder adults Those with liver disease, diabetes, Those with liver disease, diabetes,

HIV/AIDS, cancerHIV/AIDS, cancer Pregnant womenPregnant women People taking immunosuppressant People taking immunosuppressant

agentsagents

Foodborne IllnessFoodborne Illness Why so prevalent?Why so prevalent? Consumer interest in eating RAW foodsConsumer interest in eating RAW foods Grocery Foods mass produced at Grocery Foods mass produced at

– Processing plants (see Food Inc. ~ the movie)Processing plants (see Food Inc. ~ the movie) Malfunction Ice Cream Plant in Minnesota Malfunction Ice Cream Plant in Minnesota 240,000 240,000 SalmonellaSalmonella Bacteria infections~ ice cream: Bacteria infections~ ice cream:

Ready to eat foods (foreign countries) e.g.Ready to eat foods (foreign countries) e.g.– Berries (Guatemala)Berries (Guatemala)– Seafood (Asia)Seafood (Asia)

Anti-biotics in animal feeds Anti-biotics in animal feeds – bacteria develp anti-biotic resistant strainsbacteria develp anti-biotic resistant strains

Can grow even if exposed to typical antibioticCan grow even if exposed to typical antibiotic

Food Safety AgenciesFood Safety Agencies

Preservation of FoodPreservation of Food

Preventing growth of bacteriaPreventing growth of bacteria– Salt, sugar, smoke, fermentation, dryingSalt, sugar, smoke, fermentation, drying– Limit water available for bacteria growthLimit water available for bacteria growth

Pasteurization, sterilization, Pasteurization, sterilization, refrigeration, freezing, irradiation, refrigeration, freezing, irradiation, canning, chemical preservationcanning, chemical preservation

Aseptic processingAseptic processing Pasteurized: MILK & O.J.

Packaging using sterile conditions, kill all microbes (heat or chemical etc.)Packaging using sterile conditions, kill all microbes (heat or chemical etc.)

Food IrradiationFood Irradiation(symbol on right)(symbol on right)

(X-rays, UV-rays) - Does not make food radioactive(X-rays, UV-rays) - Does not make food radioactive Breaks down chemical bonds, cell walls, DNABreaks down chemical bonds, cell walls, DNA Controls growth of insects, bacteria, fungi, Controls growth of insects, bacteria, fungi,

parasitesparasites Approved for use for raw meats, shell eggs, seeds, Approved for use for raw meats, shell eggs, seeds,

dried seasoningsdried seasonings Safe according to FDA? ~ free radicals generated . .Safe according to FDA? ~ free radicals generated . . Radura symbol requiredRadura symbol required Used in many countries, although still controversialUsed in many countries, although still controversial

Why Are Microbes So Harmful?Why Are Microbes So Harmful?e.g. e.g. Bacillus, Campylobacter, Clostridium, Vibrio, Bacillus, Campylobacter, Clostridium, Vibrio,

SalmonellaSalmonella

Bacteria everywhere: 1 tsp. soil = 2 billion Bacteria !!!

Challenge QuestionWhat are the TWO Ways that microbes cause food borne illness?

1.

2.

Shiga Toxin

MicroorganisMicroorganisms and ms and

Food Borne Food Borne IllnessIllness

@ Constant risk of @ Constant risk of

foodborne illnessfoodborne illness

Animation Animation Microbial Growth vs Temp. Microbial Growth vs Temp.

&&Temperature vs SpoilageTemperature vs Spoilage

food_pathogens_final.swf

food_spoilage_final.swf

Take Break

Food Additives?Food Additives?

Limit spoilageLimit spoilage

Prevent undesirable changes in Prevent undesirable changes in color & flavorcolor & flavor

Increase safety of food Increase safety of food distributiondistribution

Food Additive ClassificationsFood Additive Classifications

Intentional food additivesIntentional food additives– Added directly to food Added directly to food e.g. (Yellow #5, BHT, sulfites, vit. C)e.g. (Yellow #5, BHT, sulfites, vit. C)

Incidental food additivesIncidental food additives– Indirectly added as contaminant (e.g., Indirectly added as contaminant (e.g.,

pesticide residues, rat poo)pesticide residues, rat poo)

Both are regulated by FDA Both are regulated by FDA

Confirming your knowledgeConfirming your knowledge

What 4 compounds constitute 98% of What 4 compounds constitute 98% of all additives used in food processing all additives used in food processing (by weight)?(by weight)?

1.1. 2.2. 3.3. 4.4.

GRAS (Generally Recognized As Safe) GRAS (Generally Recognized As Safe) ListList

Manufacturers do not have to prove Manufacturers do not have to prove safetysafety– Already regarded as safe, Already regarded as safe,

FDA FDA – Responsible for proving that a substance Responsible for proving that a substance

does not belong on GRAS listdoes not belong on GRAS list red dye #3 removed (carcinogen)red dye #3 removed (carcinogen)

Synthetic chemicals Synthetic chemicals ≤ ≤ toxicity of natural toxicity of natural products (Organic/ Natural products (Organic/ Natural ≠ safer)≠ safer)

Safety of AdditivesSafety of Additives

Tested on at least 2 animal speciesTested on at least 2 animal species– Mice, ratsMice, rats

Determine the highest dose that produces no Determine the highest dose that produces no observable effects (skin, inflammation etc.observable effects (skin, inflammation etc.

Prorate dose to a human dose (1% of toxicity~ Prorate dose to a human dose (1% of toxicity~ mice)mice)– Divide dose by 100 to establish margin of safetyDivide dose by 100 to establish margin of safety

If additive is shown to cause cancer even at very If additive is shown to cause cancer even at very high dose, it is taken off the market by FDAhigh dose, it is taken off the market by FDA– Several exceptions (nitrates, nitrites Several exceptions (nitrates, nitrites nitrosamines) nitrosamines)

-Challenge Question--Challenge Question-What is the Delaney Clause?What is the Delaney Clause?

And what are exceptions?And what are exceptions?

FDA Approval for New Food FDA Approval for New Food AdditiveAdditive

Must identify new additiveMust identify new additive Give its chemical compositionGive its chemical composition State how it is manufacturedState how it is manufactured Specify method of measurementSpecify method of measurement Outline intended purposeOutline intended purpose Provide proof of safetyProvide proof of safety Cannot to be used to deceive publicCannot to be used to deceive public

Types of Food AdditivesTypes of Food Additives

Aspartame

Nitrates/NitritesProven to cause cancerStill used b/c risk is low . .

High Fructose Corn Syrup (HFCS)~ high levels of Mercury (Hg)~ High levels of Carbonyl compounds

(Methylglyoxal)-shown to be high in people w/ Diabetes

Soda Warning? New Study Supports Link Between Diabetes, High-fructose Corn Syrup 13-Aug-2007, Source:American Chemical Society (ACS) - Newswise

(MSG)

USDA/FDA Recomendataion:-eat foods of HFCS in moderation . . .

Confirming your knowledgeConfirming your knowledge

What is the permissible % amount of a What is the permissible % amount of a food additive that has shown toxicity to food additive that has shown toxicity to laboratory animals that can be added to laboratory animals that can be added to food?food?

Natural ToxinsNatural Toxins Occur naturally in foodsOccur naturally in foods Safrole from sassafras, mace, nutmeg, cinnamonSafrole from sassafras, mace, nutmeg, cinnamon

– (used in Root beer) Known carcinogen – Banned by FDA(used in Root beer) Known carcinogen – Banned by FDA Solanine from potato shootsSolanine from potato shoots

– NIH on solanine: never eat potatoes green below the skin.NIH on solanine: never eat potatoes green below the skin.– nausea, diarrhea, vomiting, nausea, diarrhea, vomiting,

Mushroom toxins (phalloidin)Mushroom toxins (phalloidin)– Death cap mushroomDeath cap mushroom– Amanita phalloidesAmanita phalloides

AvidinAvidin TetrodotoxinTetrodotoxin Oxalic acid Oxalic acid Herbal teasHerbal teas

SafroleSafrole

solanine

phalloidin

IS Caffeine a Cause for IS Caffeine a Cause for Concern?Concern?

Causes anxiety, dehydration, insommnia, Causes anxiety, dehydration, insommnia, increased heart rateincreased heart rate

Cancers?Cancers? Worsens heartburn (relaxes sphincter muscles Worsens heartburn (relaxes sphincter muscles

in esophagus)in esophagus) Women ~500mg/day increased miscarriagesWomen ~500mg/day increased miscarriages

– FDA: pregnant women FDA: pregnant women ≤ 2 8oz coffee cup/day≤ 2 8oz coffee cup/day Improves performance in top athletesImproves performance in top athletes 200-300mg/day prudent dose, (2 cups 200-300mg/day prudent dose, (2 cups

coffee/day)coffee/day)– safe/sound for nowsafe/sound for now

theobromine caffeine

Environmental ToxinsEnvironmental Toxins

Pesticides vs OrganicPesticides vs Organic

Most healthy authorities believe benefitsMost healthy authorities believe benefits

Outweigh risks (pesticide usage)Outweigh risks (pesticide usage) Most toxicity due to chronic vs acute casesMost toxicity due to chronic vs acute cases

– extremely small exposure levels avg. humanextremely small exposure levels avg. human Growing evidence (contamination, Growing evidence (contamination,

destruction of wildlife habitats)destruction of wildlife habitats)– N. Americans should reduce pesticide useN. Americans should reduce pesticide use– (USDA + farmers working towards)(USDA + farmers working towards)

What is a pesticide?What is a pesticide?

Any substance/mixture intended to Any substance/mixture intended to prevent, destroy, repel or mitigate any prevent, destroy, repel or mitigate any pest.pest.

EPA allows 10,000 pesticides EPA allows 10,000 pesticides – (300 active ingredients)(300 active ingredients)

Benachou et al., "Glyphosate Formulations Induce Apoptosis and Necrosis in Human Umbilical,

Embryonic, and Placental Cells 2008, Chemical Research in Toxicology

glyphosate e.g. Roundup: (glyphosate)e.g. Roundup: (glyphosate)-most used herbicide in the -most used herbicide in the

USA USA - #1 selling in world, 1980- #1 selling in world, 1980- toxicity to developing - toxicity to developing

embryosembryos

Not all pesticides = badNot all pesticides = bad

e.g. fungicides prevent aflatoxin e.g. fungicides prevent aflatoxin – By product of fungal growthBy product of fungal growth

Most potent Deadly carcinogensMost potent Deadly carcinogens

-Pesticides prevent billions of food crops destroyed -Pesticides prevent billions of food crops destroyed annuallyannually

aflatoxin

How safe are Pesticides?How safe are Pesticides? Toxicity based on chronic exposuresToxicity based on chronic exposures

– Increased cancer in farm communitiesIncreased cancer in farm communities Lymph, genital, brain, digestive cancersLymph, genital, brain, digestive cancers

Some argue pesticide laden food = saferSome argue pesticide laden food = safer

vs natural product toxins e.g. peanut butter (aflatoxin)vs natural product toxins e.g. peanut butter (aflatoxin)

aflatoxin

Confirming your KnowledgeConfirming your KnowledgeHow can you Reduce Your Exposure to How can you Reduce Your Exposure to

Environmental Toxins?Environmental Toxins?

0.1.2.3.4.5.6.7.

Water SupplyWater Supply

WaterWater Bottled waterBottled water– ArtesianArtesian– DistilledDistilled– PurifiedPurified– SpringSpring– MineralMineral

Public drinking waterPublic drinking water

Challenge Question-Challenge Question-What is a good way to limit heavy metal exposure in What is a good way to limit heavy metal exposure in tap water tap water from your faucet?from your faucet?

Why should you never run Hot water from the Tap to Why should you never run Hot water from the Tap to cook with?cook with?

Avoiding Microbes at the Avoiding Microbes at the StoreStore

Buy frozen, perishable foods lastBuy frozen, perishable foods last Place meats in separate plastic bagsPlace meats in separate plastic bags Don’t buy dented cansDon’t buy dented cans

– Clostridium botulinum Clostridium botulinum toxintoxin Most toxic protein knownMost toxic protein known

– LD50 of roughly 0.005-0.05 µg/kg. LD50 of roughly 0.005-0.05 µg/kg. – AKA Botox (inhibits Acetylcholine)AKA Botox (inhibits Acetylcholine)

Buy only pasteurized milk/cheeseBuy only pasteurized milk/cheese Buy only what you need (shop 1X week or bi-Buy only what you need (shop 1X week or bi-

monthly)monthly)– buy Freshbuy Fresh

Avoid buying slimy, brownish, or dry produceAvoid buying slimy, brownish, or dry produce

–botulinum botulinum toxintoxin

Avoiding Microbes At HomeAvoiding Microbes At Home

Wash hands thoroughlyWash hands thoroughly Keep counters, cutting boards, equipment Keep counters, cutting boards, equipment

clean and sanitizedclean and sanitized Prepare raw meat separatelyPrepare raw meat separately Thaw foods in refrigerator/cold running Thaw foods in refrigerator/cold running

water/ microwavewater/ microwave Avoid coughing and sneezing over foodAvoid coughing and sneezing over food Wash fruits/vegetables thoroughlyWash fruits/vegetables thoroughly Remove mold or discard foodRemove mold or discard food Use refrigerated meat in 1-2 days; frozen Use refrigerated meat in 1-2 days; frozen

in 3-4 monthsin 3-4 months

Avoiding Microbes When Avoiding Microbes When CookingCooking

Thoroughly cook meat, fish, poultry, eggsThoroughly cook meat, fish, poultry, eggs Check for doneness with thermometerCheck for doneness with thermometer Cook sprouts until steamingCook sprouts until steaming Cook stuffing separatelyCook stuffing separately Eat food right awayEat food right away Store leftovers within 1-2 hours Store leftovers within 1-2 hours (bacteria (bacteria

growth)growth)

Serve cooked meat on clean platesServe cooked meat on clean plates Avoid partially cooking foodAvoid partially cooking food

Internal Cooking TemperatureInternal Cooking Temperature

When in DoubtWhen in DoubtThrow it out?>Throw it out?>

What To Do With LeftoversWhat To Do With Leftovers Keep hot foods hot & cold foods Keep hot foods hot & cold foods

cold (<41cold (<41°° F or >135 F or >135°° F) F) Reheat leftovers thoroughly Reheat leftovers thoroughly

(165(165°° F) F) Store peeled, cut-up produce in Store peeled, cut-up produce in

refrigeratorrefrigerator Keep refrigerator < 41Keep refrigerator < 41°° F F

AssignmentsAssignments

Diet Analysis 2 due Wednesday (10 pts.)Diet Analysis 2 due Wednesday (10 pts.) Evaluations WednesdayEvaluations Wednesday

Food Inc. Qs (5 pts) Due FridayFood Inc. Qs (5 pts) Due Friday Practice Final Online w/ answersPractice Final Online w/ answers

Final Exam this Friday (Chapters 6, Final Exam this Friday (Chapters 6, 8,9,10,11,13,16) 8,9,10,11,13,16) – Challenge & Confirming Your Knowledge Qs (the above)Challenge & Confirming Your Knowledge Qs (the above)– Old Final know all Qs and answersOld Final know all Qs and answers