Food Preservatives and Dyes

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Food Preservatives and Dyes
Carl Schroedl
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Preservatives

• Preservation aims to prevent the development of
  rancid, moldy or otherwise unconsumable food.
• Preservatives allow people to safely consume food
  products that are not in season or locally
  available.
• Methods of food preservation are many and varied.

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Curing

• Salt, spices, sugar, vinegar or sodium nitrite
  are added, sometimes used in combination with
  smoking
• End products usually very salty

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Drying

• Lack of water inhibits microbial activity
• Methods
• Sun drying
• Hot air drying
• Freeze drying

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Canning

• Used for a wide variety of foods.
• Cans are vacuum-pumped, heated and cooled
• Affects color, texture, flavor and nutrient
  content

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Refrigeration

• Low-temperature storage slows many of the
  enzymatic reactions and the growth of
  microorganisms

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Controlled Atmosphere Storage

• Chemical composition of surrounding gasses is
  changed.
• Controls the process of ripening

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Aseptic Packaging

• Package and food sterilized separately.
• Hydrogen peroxide used instead of heat

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Irradiation

• Food is exposed to gamma or X rays
• Only a limited amount of irradiated food has been
  sold

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Fermentation

• Microorganisms added to facilitate process

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Pasteurization

• Invented by Louis Pasteur
• Involves the heating of foods to kill microbes

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Additives

• Chemicals are added during processing to improve
  the looks, taste, nutritive content, and apparent
  freshness.
• Categories
• Anti-caking agents
• Humectants
• Emulsifiers
• Stabilizers / Thickeners
• Dyes
• Preservatives

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BHA/BHTbutylated hydroxyanisole

• Used to preserve fatty foods, chewing gum, baked
  goods, dry breakfast cereals and cosmetic
  products. BHA content may not exceed 0.02 of
  the total fat content of foods.
• In clinical studies, BHA caused cancer in the
  forestomach of certain animals.

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BHAbutylated hydroxyanisole
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Nitrates/Nitrite

• Some epidemiological studies have linked
  nitrate-contaminated drinking water and stomach
  cancer.
• Nitrate or nitrite exposure during pregnancy may
  adversely effect the unborn child.
• Sodium nitrite may promote the growth of
  nitrosamines
• Types
• Sodium nitrate
• Potassium nitrate
• Ammonium nitrate

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Sulfites

• Prevents discoloration
• Destroys B vitamins
• Allergenic substance
• Types
• sodium sulfite
• sodium and potassium bisulfite
• sodium and potassium metabisulfite

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Dyes

• Chemicals that affect the color of foods with
  negligible effects on taste, texture or other
  aspects

Name Common name Color
FDC Blue No. 1 Brilliant Blue FCF bright blue
FDC Blue No. 2 Indigotine royal blue
FDC Green No. 3 Fast Green FCF sea green
FDC Red No. 3 Erythrosine cherry red
FDC Red No. 40 Allura Red AC orange-red
FDC Yellow No. 5 Tartrazine lemon yellow
FDC Yellow No. 6 Sunset Yellow FCF orange
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Reporting Adverse Reactions

• The FDAs Adverse Reaction Monitoring System
  collects and acts on complaints concerning all
  food ingredients including preservatives. If you
  experience an adverse reaction from eating a food
  that contains sulfites, describe the
  circumstances and your reaction to the FDA
  district office in your area (see local phone
  directory) and send your report in writing to
• Adverse Reaction Monitoring System (HFS-636)200
  C St., S.W.Washington, DC 20204