M5S4: Food Additives Flashcards
What are food additives
-substances that are added to food to improve the appearance, texture and storage of food
-may also include substances added during the processing of food or added to improve nutritive value (ex. Adding vitamins and numerals like iodine to salt)
Classes of food additives
Intentional
-substances added to food to improve appearance, texture and storage of food
Ex. Vitamins and minerals, flavours, colours, preservatives, texture agents
Unintentional
-added inadvertently as result growing, manufacturing, storage
-termed contaminants
-amount that’s present in food limited by regulations
Ex. Fertilizers, pesticides, heavy metals, bio hazardous contamination (ex. Microorganism,, animals-by-products, hair)
Food additive regulations Canada
-conducted by food and drug regulations under authority of health Canada
-all permitted food additives and their conditions of use listed in list of permitted food additives
-if not on list, manufacturer required to submit information on proposed use, evidence of safety, information on effectiveness of additive which then evaluated by health Canada scientists before approval granted
Why are regulations more stringent for food additives then OTC drugs
-food additives consumed without our knowledge, most of the time, you do not know their presence even if must be on label
-taken for lifetime by entire population
-healthcare professionals not involved with food additives and therefore not available to give advice regarding food additives in same way as drugs
-young children exposed during vulnerable periods
-not essential for life
Determining toxicity of food additive
-risk/benefit ratio must be carefully determined
-technique used to determine risk/benefit is to study toxicity in animals then extrapolate the results to humans
Exposure
-extent of exposure difficult to replicate in animals
-administered to animal for one or two years while humans can be exposed entire life
-risk estimates must be made on lifetime of exposure
Assumption of risk
-usually tested in animals at highest no-effect dose calcium
-acceptable human dose taken as 1/100 or 1/1000 or maximum no-effect dose in animals
-assumption made that studying high dose in animals mimic low dose, lifetime exposure in humans
-humans exposed based on estimates of intake of that particular food but luckily the assumptions tend to overestimate actual risk
Carcinogenic
Having potential to cause cancer
Food additives as carciongens
-food additives carefully tested and if positive response, compound not allowed for food additive normally
Rational use of food additives
-WHO adopted few principals concerning food additives
Function:
Use of additives is justified if they enhance or maintain quality or acceptability of food
Quality:
Additives should be used only in quantities sufficient to obtain stated ends
Purity:
Additives should be pure
Toxicological evaluation:
Should be undertaken
Information should be gathered and utilized to determine potential risk of the food additive and whether further study is needed
Special groups:
Should be considered
Special populations: heavy drinker and cobalt chloride
-past bunch of people died from heart disease cause cobalt chloride (inhibitor of heart muscles) added to beer to control amount of foam
-risk assessment determined individual need to consume 24 beer every day for long periods of time to receive toxic dose of colbalt chloride. Unfortunately some did and died so no longer added to beer
Current concerns with food additives
-“I mistrust use of additives”
-“natural additives can also be harmful” ex. Some natural food colouring has been shown to be carcinogenic in some animal studies so not allowed to be added to food but are natural in some food
-“children are exposed to additives” could increase hyperactivity
Class: Flavoring
-quiet prevalent in foods
-thousands used, testing has not be as throughout as other additives but toxicity quite rare
Flavoring agents
-includes substances such as Flavoring agents and enhancers, essence of smoking and synthetic flavours
-since 1976, are increase in use of stimulated flavours, additives are mixtures of artificial flavours
Evaluation
-difficult to evaluate such large number of substances
-4 to 5 thousand Flavoring are in use and most have not been adequately treated but approved due to experince obtained over years
Toxicity
-very few Flavoring demonstrate toxicity
-however monosodium glutamate (MSG) causes tightening of muscles in face and neck, accompanied by headache, nauseas and giddiness
Class 2: colours
-organic dyestuffs added to give food appetizing appearance
-most well evaluated
-allergic reactions have occurred, the most common to tartrazine, yellow food colour
-if individual allergic to aspirin, may also be allergic to tartrazine
-Canada allows 10 food colours, USA 11, Denmark 33
-Canada banned Red dye no. 2 as produce cancer in experimental animals when high dose
-may have acceptable appearance for average person to maintain adequate diet
Class 3: texture agents
-added to improve or impart specific texture
-located in food in relatively high concentration of up to 1-3% of product
-poss little or no toxicity
Silicates
-added to flour and flour products to keep them free flowing
Emulsifying/thickening (gums, agar)
-added to frozen food like ice cream and sherbet
Class 4: preservatives
-more rational use
-allows for delivery of food to distant destinations and ensure appropriate quality of food for consumer
-in most case benefit outweigh risk
-2 main types
Antibacterials
-3 types
1. Smoke ->
-old-age method of preserving food, mainly meet
-major concern that natural smoke Carrie’s small carcinogenic risk
-some of currently used smoke Flavoring products had carcinogens removed
2. Antibiotics ->
-most effective
-not used in Canada to prevent emerge of antibiotic resistant organisms
3. Sodium nitrate ->
-controversial so want to reduce attempts
-added to meat to impart a pleasing red colour to prepared meats and inhibit growth of clostridium botulinum
-adverse effects include nitrosamines, that known as carciongen
Antioxidant
-prevent oxidation and thus rancidity and discolouration of fooods
-improve storage and quality of product
-2 types
1. Water soluble - added to foods to reduce oxidation of carbohydrates (ex. Browning of fruit)
-agents most commonly used are ascorbic and citric acids
2. lipid soluble - added to prevent fats from becoming rancid (ex. Oxidizing)
-used in large number of foods (ex. Chips, cookies, cakes)
-some cause liver damage
-tocopherols (vitamin e) also used as antioxidants
-less effective than some other antioxidants used but possess lower toxicity risk
Class 5: sweeteners
-sugar most common
Others:
-saccharin - >
-First artificial sweetener developed and added to numerous products
-resitricted in Canada based on studies linking it to cancer but 2016 did safety assessment and removed restriction
Aspartame ->
-replaced saccharin
-only toxicity is phenylketonuria (inability to metabolize phenylalanine (an amino acid in aspartame) that can result in brain and nerve damage) that clearly stated on label
