Transcript Food Additives power point Chapter 24

Food Additives
Chapter 24
• Any substance a food producer intentionally adds to a
food for a specific purpose.
• Producers use around 3,000 additives to preserve and
improve foods.
What is a Food Additive?
• Natural: occur naturally in food or specific parts of
plants. Ex. Salt and sugars
• Synthetic: additives made in a laboratory. Their
chemical “ingredients” are the same as any that occur in
nature, but the chemicals are joined or modified in the
food science lab.
Natural & Synthetic
• Food & Drug Administration (FDA) – responsible for
making sure food is safe to eat, nutritious, and honestly
represented.
• Delaney Clause –. states that no substance shown to
cause cancer in humans or animals may be added to food
• GRAS list (about 670 items) – “generally recognized as
safe” – contains substances such as spices, natural
seasonings, and flavorings that are considered safe for
human consumption and not regulated as additives.
• GRAS list
Regulating Additives
• FDA uses food labeling to hold manufacturers
accountable for additives used.
• There are strict rules on how additives are identified on
labels
• “flavored” means natural flavorings; “artificially
flavored” contains some, and possibly only synthetic
flavorings.
Food labeling
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To improve storage properties
Increase healthfulness
Make food more appealing
Improve processing and preparation
How additives are used
• Food suppliers need to get food items to consumers
before mold and contamination ruin the product.
• Common chemical preservatives include sodium nitrite,
sorbic acid, sodium bisulfite, and sodium nitrate
• Some natural substances that can be used as preservatives
are salt, acetic acid (vinegar), sugar and spices (none are
considered additives).
Improving storage
properties
• Fortification: adding nutrients that are not normally
found in a food.
• Restoration: nutrients lost in processing are returned to
the food.
• Enrichment: similar to restoration, but add more
nutrients than the food had before processing
• Nutrification: process that adds nutrients to a food with
a low nutrient/kcalorie ratio so the food can replace a
nutritionally balanced meal.
Increasing Healthfulness
• Color – some color is made from food, but most are
made artificially (identified by number)
• affect of food dyes on children
• danger of food dyes
• Flavor – most added flavors are artificial
• Flavor enhancers – impart no flavor of their own, but
enhance the flavor already in food
• Monosodium Glutamate (MSG) is an enhancer that
react allergically in some people
Making food more
appealing
• Nutritive sweeteners: metabolize to produce calories,
i.e. sucrose, brown sugar, maple syrup, molasses and
honey
• Sorbitol – glucose based, sugar alcohol has as many
calories as sucrose, but tastes only half as sweet. Used by
dieters; doesn’t metabolize as well as sucrose (used in
sugarless gum)
Sweeteners
• Nonnutritive sweeteners – artificial sweeteners
• Sucralose – made from sugar, but is 600 times sweeter – no
calories – suitable for baking
• Saccharin – made from petroleum products – 300 times as
sweet as sucrose – no calories - may leave bitter taste
• Aspartame – 200 times sweeter than sugar – no calories –
can’t be used in baked goods – loses sweetness in beverages
(use-by-date)
• affects of aspertame
• more dangers of aspartame
• Acesulfame potassium (acesulfame K) – highly stable,
crystalline, calorie-free sweetener – 200 times sweeter than
sugar; used in baked goods.
Sweeteners
• Stabilizer – substance that keeps a compound, mixture,
or solution from changing its form or chemical nature.
• Thickeners are stabilizers that contribute smoothness or
body to a food.
• Both are usually natural additives
• Starch based – pectin, casein, sodium caseinate, gelatin
• Gum based – extracted from bushes, trees and seaweed
• Buffers – used to achieve desired pH in preparing and
preserving foods (citric acid, sodium citrate, lactic acid)
Improving Processing
and Preparation
• Not enough is known about long-term effects of using
additives
• Nitrites (and nitrates)– used for centuries in cured meats;
but under intense heat, react with meat to form
nitrosamines which are suspected of causing cancer.
However, nitrites prevent botulism (which kills)
• Saccharin – “could” produce cancer in lab animals
• Some have allergies to such preservatives as sulfites,
MSG, and BHT
Concerns about Food
Additives
• Some fruits and vegetables are treated with a light coat of
oil-based waxes – FDA approved – seals in moisture
• Unnatural standards encourage people from eating what’s
really good for them.
• Artificial flavors may be preferred over the real thing
Unneeded Additives
• Safety – consumers and producers rely on additives to
help ensure a safe food supply
• Calcium propionate – mold inhibitor
• BHT – keeps fats from going rancid
• EDTA (ethylenediamine tretraacetic acid) helps prevent
rancidity
Value of Food Additives
• Improved Nutrition – additives prevent diseases caused
by malnutrition
• Goiter – an enlargement of the thyroid gland caused by a
lack of iodine – iodine added to table salt in 1924 to
eliminate goiter
• Adding Vitamin D to milk to combat rickets
• Fortifying flour and cornmeal with iron and niacin
reduces pellagra
Value of Food Additives
• Additives allow people to enjoy a more varied diet
• More food is available to the people who need it
• Used responsibly, chemical additives are no more
dangerous than the food itself
• additives allowed in organic foods
• What is Xanthan Gum?
• Agar Agar
• Use for Agar-AgarTapioca Maltodextrin
Value of Food Additives