Unit 4: Food Additives

Table of Contents

Introduction to Food Additives

Definition

A food additive is any substance not normally consumed as a food by itself, which is added intentionally to food, usually in small quantities, to achieve a specific technical purpose (e.g., to affect its keeping quality, texture, color, or taste).

Objectives and Principles

  • Objectives:
    1. Preservation: To improve shelf-life and prevent spoilage (e.g., anti-microbials, antioxidants).
    2. Sensory Appeal: To enhance taste, aroma, texture, and appearance (e.g., sweeteners, colorants, emulsifiers).
    3. Processing Aid: To assist in the manufacturing process (e.g., anti-caking agents).
    4. Nutritional Enhancement: To fortify or enrich food with nutrients (e.g., adding Vitamin D to milk).
  • Principle: The primary principle is safety. Additives must be "Generally Recognized As Safe" (GRAS) by regulatory bodies (like FSSAI or FDA) and used only at the minimum level necessary to achieve the desired effect.

Types of Food Additives (Preservatives)

These additives prevent spoilage from bacteria, molds, fungi, or yeast.

Preservative Type Examples Function & Use
Benzoates Sodium Benzoate (E211) Antimicrobial (anti-fungal/bacterial). Used in acidic foods like soft drinks, jams, and pickles.
Propionates Calcium Propionate (E282) Anti-molding agent. Widely used in baked goods (bread) to keep them fresh.
Sorbates Potassium Sorbate (E202) Inhibits molds and yeasts. Used in cheese, wine, yogurt, and dried meats.
Disulphites (Sulfites) Sodium Disulphite (E223) Antioxidant and antimicrobial. Used in wine, dried fruits (prevents browning), and juices. Can cause allergic reactions in some people.

Artificial Sweeteners

These are non-nutritive (zero or low-calorie) substitutes for sugar, often many times sweeter.

  • Aspartame: (e.g., Equal, NutraSweet). ~200x sweeter than sucrose. Composed of two amino acids. Unstable to heat (cannot be used in baking).
  • Saccharin: Oldest artificial sweetener (~300-400x sweeter). Stable to heat. Had past health concerns (now largely considered safe).
  • Dulcin: ~250x sweeter. Banned in many countries (e.g., USA since 1951) due to toxicity concerns (carcinogen).
  • Sucralose: (e.g., Splenda). ~600x sweeter. A modified sucrose molecule. Stable to heat (can be used in baking).
  • Sodium Cyclamate: ~30-50x sweeter. Banned in the USA due to cancer concerns in animal studies, but permitted in many other countries (e.g., Canada, EU).

Flavours

These are added to food to impart a specific taste or aroma.

  • Vanillin: The primary chemical component of vanilla bean extract. Widely used as a flavor in ice cream, chocolate, and baked goods.
  • Alkyl Esters (Fruit Flavours): Esters are simple organic compounds that often have strong, fruity smells. They are used to create artificial fruit flavors.
    • Example: Isoamyl acetate (banana)
    • Example: Ethyl butyrate (pineapple)
    • Example: Octyl acetate (orange)
  • Monosodium Glutamate (MSG): The sodium salt of glutamic acid (an amino acid). It is a flavor enhancer that imparts the "umami" (savory) taste. Used in processed foods, soups, and Chinese cuisine.

Artificial Food Colorants

These are dyes added to food to restore color lost during processing, enhance natural color, or provide color to 'fun' foods (e.g., candy).

Coal Tar Dyes

These are synthetic (artificial) colors, originally derived from coal tar, though now synthesized from petroleum. They are cheap, stable, and produce vibrant colors.

  • Examples (Permitted Dyes): Tartrazine (Yellow No. 5), Sunset Yellow (Yellow No. 6), Allura Red (Red No. 40).
  • Concerns: Some (like Tartrazine) can cause allergic reactions in sensitive individuals.

Non-permitted Colors and Metallic Salts

These are dangerous and illegal substances sometimes used by unethical producers (adulteration) to color food, often because they are cheaper.

  • Metanil Yellow: A non-permitted industrial dye, illegally used to color *turmeric powder* and *laddoos* bright yellow. It is toxic and carcinogenic.
  • Metallic Salts:
    • Lead Chromate (PbCrO4): A bright yellow, highly toxic lead salt, illegally used to color turmeric.
    • Malachite Green: An industrial dye (and anti-fungal for fish) illegally used to make peas and chilies look greener. It is toxic.