Download FOOD ADDITIVES

FOOD ADDITIVES
Definition
• Any substance added to food
during production, processing,
treatment, packaging,
transportation or storage.
Why do products have food additives?
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To improve flavour or colour
To improve texture
To preserve (slow down speed of rotting)
To add nutritional value
• Direct additives are added to a food for
a specific purpose and are identified on
the ingredient label of the food.
• Indirect additives unintentionally
become part of the food in trace
amount due to its handling, packaging,
etc.
• Excessive levels of an additive or
inclusion of an undeclared additive may
be directly dangerous in some instances.
Food Manufacturers Must…
• Test food additives to show that they are safe
• Prove the additive is needed
Create a Chart
Food Additive
Important Info (look for *)
Migration of Packaging
• Plastic consists of its polymer,
plasticizers, antistatic agents, stabilizers
and antioxidants, etc.
• Some components are more likely to
migrate into foods than others, esp.
residual plastic monomers and
plasticizers.
• The plastic monomers of most health
concern are vinyl chloride, and styrene.
1. Vinyl Chloride Monomer (VCM)
• The monomer of polyvinyl chloride (PVC).
• It leaches into both water and fats.*
• Typical products that absorb VCM are bottled
mineral water and cooking oils.*
• It also the most available for migration from the
‘cling films’ that are used for all kinds of foods.
• Vinyl chloride has been identified as a liver
carcinogen in animal models as well as in humans.
• Acute intoxication causes depression of the central
nervous system and hepatic damage *
2. Styrene
• Styrene prefers to leach into fats.
• Typical sources of styrene: deli packaging (sausages,
ham, smoked beef/ bacon/ fish, etc) and yoghurt
cups. *
• Styrene-induced toxic effects include renal and
hepatic damage, pulmonary edema, and cardiac
arrhythmia. *
3. Plasticizers
• Important plasticizers in PVC plastics are the phthalic
acid esters di-(2- ethylhexyl) phthalate (DEHP) and din-butyl phthalate (DBP).
• However, liver or lung damage by the leached
plasticizers has been suggested. DEHP and DBP
appear to be non-genotoxic carcinogens.
• Since they are widely distributed in materials
involved in transportation, construction, clothing,
medicine, and packaging, the concern about their
health effects has increased.
• Different plastics and forms are designed for specific
product containment situations.
• Use of this plastic packaging in a manner other than
that for which it was designed may cause significant
migration of plastic compounds into the food. *
Situation that can promote contaminants
migration:
• Heating containers (by microwave oven) which are
designed solely for chilled foods.
• Overheating ‘heat resistant’ containers.
• Coming close to laminating leftovers covered with
cling wrap in the microwave.
Following the instruction on the label / packaging is
important!
Food Additives are shown using:
• E numbers (e.g. E440)
OR
• A chemical name (e.g. pectin)
OR
• Can have both
Thinking in Numbers…
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E100 series = colour
E200 series = preservatives
E300 series = antioxidants
E400 series = miscellaneous
Nitrates, Nitrites, and N-nitroso compounds
• Nitrates (NO3) and nitrites (NO2) are used to preserve
meat products, such as bacon, ham, hot dogs, and
cold cuts.*
• The addition of nitrite can give desirable color to
meat products (pink) and flavor, retards fat oxidation,
and prevent bacterial growth (especially Clostridium
botulinum).
• Nitrites was intentionally added to meat in the 16th
or 17th century.
1. Nitrites
• Nitrite inhibits the bacterial production by inhibiting
certain enzymes within the microbe and on its cell
membrane.
• Nitrite weakens the bacterial spores, reducing the
like-hood of germination.
• Nitrite is very reactive and can be directly toxic or
form carcinogenic N-nitroso compounds.
• It can oxidize blood oxyhemoglobin (ferrous form) to
methemoglobin (ferric form).
2. Nitrates
• Commonly found in water and vegetables, especially
those grown with high-nitrate fertilizer. *
• It has low reactivity  not toxic.
• However, nitrate becomes a hazard when it is
reduced to nitrite! Dietary nitrates can be converted
to nitrites during digestion.
• Cases of life-threatening methemoglobinemia when
the patient’s diet contained too many nitrate sources
(e.g. drinking water and spinach) within a short time
span.
3. N-nitroso compounds
• Nitrosamines are found in cured meat products and
malt products (beer). *
• Another case: nitrosamine in rubber baby bottle
nipples!
• Nirosamides are direct mutagen.
• They can be decomposed at mild alkaline condition
or destroyed by cooking.
• The mutagenic/carcinogenic potential of nitroso
compounds in animal models is well documented,
but the toxicity to humans is not proven.
Sulfites
• Sulfites (SO3) are used as antioxidants to prevent
enzymatic browning, inhibit bacterial growth (in
wine), bleaching agent, dough conditioner, to
prevent melanosis on shrimp, and in the production
of some food packaging.
• They are present in the form of sulfur dioxide,
sodium sulfite, sodium metabisulfite, sodium
bisulfite.
Acidulants
• Many foods are acidic and have sharp, sour
taste
• E.g. Lemons contain citric acid
• E.g. Cheese and Yogourt contain lactic acid
• Added for taste and act as a preservative
• Found in: soft drinks, desserts, jams, sweets,
soups and sauces
• Individuals with asthma problem are sensitive to
sulfites. *
• GRAS (Generally Recognized As Safe) since 1959, but
then they are banned by FDA (1986) after reported
causing some health problems when they used to
maintain the color and crispness of the salad greens.
• Sulfites sprayed onto foods produce the most rapid
allergic reactions. *
• Sulfites can destroy thiamin  banned by FDA to be
used in important sources of the vitamin (e.g.
enriched flour).
Salts
• An important food additive for prevention of bacterial
growth, for necessary technical reason, or for flavor.
• The chemical name for salt, sodium chloride, reveals
that sodium is in fact a component of salt. *
• Both sodium and chloride ions are important in
physiological processes, but excess sodium directly
cause hypertension (high blood pressure), a major risk
factor for heart disease, stroke and kidney disease. *
• The typical modern consumption of sodium is 10-20
times the amount needed for physiological balance.
*
• Potassium containing table salt substitutes can cause
hyperkalemia in high dose.
• FDA limit sodium to 2400 mg daily for a 2000- calorie
diet.
• The best way to reduce salt intake: read labels and
make educated choices!
Sodium labelling defined by FDA:
• Sodium free or salt free: Less than 5 mg per serving
• Very low sodium: 35 mg or less of sodium per serving
• Low sodium: 140 mg or less of sodium per serving
• Low sodium meal: 140 mg or less of sodium per 3 ½ oz
• Reduced or less sodium: At least 25% less sodium than
the regular version
• Light in sodium: 50% less sodium than the regular version
• Unsalted or no salt added: No salt added to the product
during processing
Nonnutritive sweeteners
• Low calorie sweeteners, such as saccharin,
aspartame, acesulfame.
Saccharin
• It is 300 times sweeter than sugar.
• It is not metabolized  no calories. *
• Saccharin has low direct toxicity  has a threshold.
• It comes in the forms of pure saccharin, ammonium
saccharin, calcium saccharin, and sodium saccharin.
Aspartame
• Approved in 1981 as artificial sweetener.
• It is 200 times sweeter than sugar and has the same
number of calories per teaspoonful. *
• Chronic methanol exposure can cause visual impairment.
• Phenylalanine can interfere with amino acid transport
and lead to nervous system disturbances  only a
problem in people with the rare genetic disease
phenylketonuria (PKU) – unable to metabolize
phenylalanine properly.
• When aspartame containing product are heated or
stored for a long period, aspartame can be decomposed
into diketopiperazine (DKP), a tumor agent.
Stevioside
• A natural sweetener from Stevia rebuadiana plant.
• It is 200-300 times sweeter than sugar and have no
calories. *
• It was used as a common sweetener in Japan (herbal
teas) during 1980’s.
• It was banned in 1991 because of the lack of formal
toxicological evaluation proving its safety.
• It is not allowed in Canada and some EU. *
• Some current studies indicate that steviol, a
metabolite of stevioside may have toxic effect (EC).
• Ironically, stevia is allowed as a nutritional
supplement (FDA Import Allert 45-06, 1996).
Color additives
• FD&C color  safe for foods, drugs and cosmetics. *
• Certified color belong to four classes: azo dyes,
triphenylmethane dyes, xanthene dyes and
sulfonated indigo dyes.
• Some colorants have been de-listed due to their
carcinogenic potential
TOP 10 FOOD ADDITIVES TO
AVOID
Copy down the additive and where to find it!
1. Acesulfame-potassium (aka
acesulfame-K)
• Where it’s found: Baked goods, chewing gum, gelatin
desserts, soft drinks, energy drinks
What it is: An artificial sweetener about 200 times sweeter
than sugar
Why avoid this additive: Two animal studies suggest that
this additive could be cancer-causing, though other studies
say it’s safe. It also breaks down into a substance—
acetoacetamide—that in large quantities has been found to
affect the thyroid in dogs, rabbits and rats. Watch for it in
foods that use sucralose, an artificial sweetener—
acesulfame-potassium is often used in conjunction with it.
2. Aspartame
• Where it’s found: Several sugar substitute products; an array of diet
foods including sodas, drink mixes and low-calorie frozen desserts;
chewing gum
What it is: An artificial sweetener
Why avoid this additive: Controversy over aspartame’s safety has
swirled since the '70s, when studies done on rats suggested it may
cause brain tumours. More recent animal studies have now linked
aspartame to lymphomas, leukemia and breast cancer. As well,
some people show an acute sensitivity to aspartame, suffering
headaches and dizziness shortly after consuming it. And to top it all
off, not only have "diet" products containing aspartame not been
shown to aid in weight loss, they may even cause you to eat more.
3. Sodium nitrite, also known as
sodium nitrate
Where it’s found: Bacon, ham, hot dogs, lunch meats and
other processed meats
What it is: It's used as a preservative, as well as for
flavouring and colouring (it stabilizes the red colour of
cured meats, preventing them from turning grey). It also
hinders the growth of bacteria that may cause botulism.
Why avoid this additive: Sodium nitrite can cause the
formation of nitrosamines, which are cancer-causing
chemicals; this reaction occurs especially in bacon. Look for
bacon products that contain ascorbic acid or erythorbic
acid; both are safe additives that help inhibit the potentially
dangerous reaction.
4. Partially hydrogenated vegetable
oils
Where it’s found: A wide variety of processed foods, especially
shortening and some margarines, deep-fried foods, cookies, baked
goods and snack foods. Many products have shifted to using
alternatives; it's important to read labels.
What it is: A processed type of fat that helps increase shelf life and
improves the texture of some processed foods
Why avoid this additive: The process to make partially
hydrogenated vegetable oil creates trans fats, which may contribute
to an increased risk of heart disease and diabetes. Many companies
have removed or are in the process of removing trans fats, so there
is almost always a trans-fat-free alternative.
5. Propyl gallate
Where it’s found: Some vegetable oils, meat products,
potato sticks, chicken soup base and chewing gum
What it is: An antioxidant preservative that keeps fats
and oils from spoiling (oxidation causes spoilage,
changes flavours and leads to colour loss)
Why avoid this additive: Reputable mice and rat
studies have shown a possible cancer link. Propyl
gallate is often used with both BHA and BHT (below).
6. BHA (butylated hydroxyanisole)
and BHT (butylated hydroxytoluene)
Where it's found: Breakfast cereals, gum, vegetable oil,
chips; may also be used in food packaging to maintain
freshness
What it is: Like propyl gallate, these are antioxidants
that prevent fats and oils from spoiling
Why avoid this additive: Some rat, mice and hamster
studies suggest these agents can cause cancer, while
others show they're safe. But BHA and BHT are easily
avoided, as many brands use safer packaging processes
and/or safer chemicals (such as vitamin E), or don’t use
an antioxidant agent at all.
7. Brilliant Blue FCFC (aka Artificial
Blue 1)
Where it’s found: Drinks, candy, baked goods
What it is: An artificial colour (see below)
Why avoid this additive: General testing has
been inadequate, there have been some
suggestions of a slight cancer risk.
9. Erythrosine (aka Artificial Red 3)
Where it’s found: Cherries in fruit cocktail,
candy, baked goods
What it is: An artificial colour (see below)
Why avoid this additive: In the ’80s, the FDA
recommended the dye be banned after
studies presented convincing evidence it
caused thyroid tumours in rats. It’s still in use
worldwide.
10. Sunset Yellow FCF (aka Artificial
Yellow 6)
Where it’s found: Some beverages, sausage,
baked goods, candy, gelatin desserts
What it is: An artificial colour (see below)
Why avoid this additive: Animal studies
sponsored by the food industry have turned up
evidence of tumours in the adrenal gland and
kidney related to this, the third-most widely used
dye. It may also cause some allergic reactions.
Are there any additives?
2. How many ingredients are present in smaller amounts than salt?
3. What can you infer of the food additives in relation to salt?
Homework
• What job/function does xanthan gum (E415)
have in food? (In particular salad dressing)
• Pick a food item off of your food diary from
any day. Be sure it is an item that you have
access to the ingredients list. At home, write
down all of the ingredients for this product
and identify any/all of the food additives listed
in the ingredients list.