Food Additive

Food additives = are substances or chemicals that are intentionally added to products to influence its structural & functional properties

Food components = are substances that are naturally inherent in product or intentionally added for nutritional reason (not to alter functional properties)

  • ex) protein, carbs, fat , vitamins, minerals already present in food are not additive

  • ex) fortifying milk with Vit D (is not food additive it serves as nutritional property)

Food additive types

  1. Direct additives (added directed to food intentionally)

    • 3 main groups

      • Food processing aids (functional additive)

      • Food preservatives

      • Food quality Enhancers

Food processing aids

  • They modify food textures

  • improve food quality and consistency

    • Emulsifiers (lecithin, mono & diglycerides)

      • Mix ingredients that do not blend well (prevent separation)

      • emulsifiers are amphipathic (polar & non-polar ends) Polar end binds to water polar compounds, and non-polar binds to lipids to stabilize the emulsion

      • make products such as salad dressing & mayo

    • Thickeners (starch, gums , pectin, CMC)

      • increase the viscosity (make liquid thicker)

      • provide a creamy consistency (improve texture)

    • Water binding agents

      • Humectants 保濕劑(retain moisture)

        • keep products moist and juicy

        • prevent products from being dry

        • ex: glycerols, phosphates, polyphosphates

      • Anti-caking agents抗結塊 (to reduce moisture)

        • keep products dry and from clumping

        • pull moisture out of the food

        • ex: cornstarch & silicates & magnesium stearate

        • anti-caking reduce water activity so can act as preservative

Food preservative

  • some methods to control microbial growth

    • Fermentation (so convert sugars to other compounds like acids to create harsh environment for microorganisms)

    • Humectants (bind to water in food to reduce free available water in the environment to control microorganism)

      • alcohols that act to reduce water activity and slowdown microbial growth & enzyme activity

    • Acids (lowering pH to control microorganism) (Acetic acid like vinegar used for pickling)

  • Food storage life extender

    • Antioxidants (prevent from oxidative damage)

      • donate electrons to free radical to neutralize

      • act as sacrificial protection

    • chelating agents (to bind to metal ion that catalyzes oxidation) (EDTA)

    • Modified atmosphere packaging (MAP)

      • replace the gases with CO,N², and CO²

      • modify or deplete air & oxygen

      • there is vacuum packaging (air oxygen completely removed to create vacuum)

Gas sterilants & Synthetic metabolic inhibitors are used to sterilize food processing equipment = used to prevent food from being contaminated and spoiled

Inorganic compounds like sulfites & nitrites

  • Nitrites

    • control clostridium

    • and give meat its bright color

  • Sulfites

    • decline the pH environment (not conducive for microbial growth)

    • prevent or reverse enzymatic browning

Food quality enhancer

3 types (to enhance flavor and sensory attributes)

  • Flavouring agents

  • Organic flavors

  • Nutritional additives

a) Flavoring agents

  • natural types (sugars, salts, spices)

  • artificial types (aspartame)

b) organic flavors (3 types to produce them)

  • extraction of natural flavors (cocoa, coffee, tea)

  • fermentation (fermentation of pineapple skin = MSG)

  • chemical synthesis

c) nutritional additives (3 categories)

added to enhance nutritive value of food

  • Restoration

    • add back the lost nutrition during food processing

  • Enhancement

    • additive of nutrition into food (Vit B to flour)

  • Fortification

    • additive of nutrition to address health need

Policy on Use of Food additive

3 Criteria Used

(must be safe for human to consume over a period time without adverse reaction)

  • must be safe for continuous use

  • must not be deceived

  • must be in consumer’s advantage

Food Additive Policy

test with at least 2 experimental animals (those data will be used to determine the ADI (acceptable daily intake) of that additive

  • short term studies

    • daily or weekly measurement of appearances, body weight, appearance

  • long term studies

    • study of offsprings, fetal malformations, incidence of tumor in parents, lactation index

Acceptable Daily Index (ADI) = maximum amount that is found to elicit no adverse effect is divided by 100

The Deception Factor

  • used additive to mask the defects in products

  • ex: feeding water-binding agent to chicken to make them gain weight in chicken

    • using reducing agent like cysteine & sulfites for crabs & vegetables and fruits to reverse enzymatic browning for discoloration

Consumer advantages

  1. improve nutrition value

    • add minerals or vitamins to food

      • addition of VitC to fruit juice

      • vitamin A&D to skim milk

  2. improve quality

    • emulsifier for emulsion

    • antioxidant for rancidity

    • antimicrobial for spoilage

  3. improve quantity

    • use of isopropyl alcohol to recover meat scrap from bone & use TGase to glue to small piece into larger chunk

Food coloring agents

Synthetic food flavors & natural food flavors

  • synthetic food

    • produced in lab by chemical synthesis

    • certified colors (pass safety evaluation)

    • ex: Blue No.1 (anything that has color in it)

  • natural food flavors (uncertified food colors)

    • extract from living organisms

    • not certified (because does not need to go through same safety test)

    • ex: derived from plants, animals, microbial

    • ex: annatto, caramel,pumeric,chlorophyllin

Certified food colors differ from different countries

They do not allow certified color to be added to unprocess food (may affect appearance and affect evaluation of freshness)

Certified Colors have 2 forms (dyes & lakes)

  • Dyes

    • water-soluble (suitable for water-base products)

    • Na or K salts chemical

    • granules & powder & liquid form

    • longer shelf-life 比較乾燥

    • paper-based container & pouch

  • Lakes

    • fat-soluble (water-insoluble)(suitable for fat-based)

    • pastes & dispersion

    • Ca or Al (aluminum) salts chemical

    • shorter shelf-life潮濕

    • in plastic jar

Food regulation for Canada = Health Canada

  • food & drug regulation

  • Marketing authorization

  • permitted food additives in canada

Indirect additives substances unintentionally become a part of food during processing, packaging or storage

  • ex) chemical substance from plastic container leaks into food

  • ex) pesticides for agriculture

  • They are unintended added into food (consider as contaminants)