ERT 426 Food Engineering Semester 1 Academic Session 2017/18 Food Ingredients ERT 426 Food Engineering Semester 1 Academic Session 2017/18

Subtopics Food ingredients plants. Properties of foods. Food Additives Food safety in Malaysia ERT 426 Food Engineering

1. Food ingredients plants Food ingredients plants utilize agricultural and natural raw materials to separate and recover valuable food components, such as wheat flour, sugar, edible oils, pectin, protein, and salt, which are used in the manufacture of several food products. Wheat flour and other cereal flours can be considered as food ingredients, which are used in large quantities in the baking and other food industries. ERT 426 Food Engineering

Food ingredients plants Various other food ingredients, used in smaller quantities, are produced by the Chemical Process Industries, examples: flavors and gums, coloring materials, sweeteners, antioxidants, preservatives, vitamins, nutritive minerals, and special food chemicals. ERT 426 Food Engineering

Food ingredients plants The raw materials of the natural food ingredients are bulk agricultural products of relatively low cost, such as cereal grains (wheat, corn), sugar beets or sugar cane, and soybeans. Some food ingredients are produced from byproducts of food preservation or food manufacturing plants, e.g., pectin from citrus or apple peels, and protein from cheese whey. ERT 426 Food Engineering

Food ingredients plants Table 1: Food Ingredients Plants. Food Ingredient Category Processing Plant Food flours Wheat, Other grain, Soya Sugars / starches Beet sugar, cane sugar, Starches, modified starches Corn syrups Food biopolymers Pectin, Cellulose, Gelatin Whey protein, Soy protein ERT 426 Food Engineering

Food ingredients plants Table 1: Food Ingredients Plants. Food Ingredient Category Processing Plant Vegetable oils Soybean oil, Corn oil, Rapeseed oil, Olive oil Plant extracts Flavors, colors, Hydrocolloids Gums, Phytonutrients Food chemicals and biochemicals Vitamins, Amino acids, Antioxidants, Acidulants Preservatives, Enzymes ERT 426 Food Engineering

2. Properties of foods Foods are composed of chemicals, and for food manufacturers it is the chemical composition that determines all aspects of their products: from the suitability of raw materials for use in particular products and processes, to the sensory characteristics and nutritional value of the processed foods, as well as wider issues such as food safety and quality assurance, traceability, product development and labelling. ERT 426 Food Engineering

Properties of foods Chemical components of foods are divided into: the macromolecular components (carbohydrates, lipids, proteins), water, which is a major component of many foods, the micro-components (vitamins, minerals, natural colourants, flavours, toxins and additives). ERT 426 Food Engineering

3. Food Additives Food additives are artificial or natural chemicals, purposely added to food (directly or indirectly) which affecting the characteristics of the food e.g: to preserve flavor or enhance its taste and appearance.

Food Additives Emulsifier Nutrient supplements Stabilizers/Thickeners Antioxidant Acidulants Enzymes Flavoring agents Coloring agents Antibrowning agents Dough conditioners Humectants Curing agents Sweeteners

3.1 Emulsifiers Chemicals that reduce the surface tension in the surface of a liquid are known as `surfactants' `emulsifying agents' or `detergents'. By reducing the surface tension, they permit new surfaces to be produced more easily when energy is put into the system (e.g. by homogenisers) and thus enable larger numbers of droplets to be formed.

Emulsifiers There are naturally occurring surfactants in foods, including alcohols, phospholipids and proteins, and these are sometimes used to create food emulsions (e.g. using egg in cake batters). However, synthetic chemicals have more powerful surface activity and only require very small amounts to create emulsions.

3.2 Stabilizers & Thickeners To control the consistency of liquid & semi-liquid food and prevent separation of food components during processing and storage other functional properties: suspending, setting, gelling and bulking properties Examples: Sodium alginate – stabilizer in ice cream Carrageenan - stabilizer in evaporated milk

Stabilizers & Thickeners Nutritional and nutraceutical Arabic and guar gum, have been used as sources of soluble dietary fibre (nutraceutical benefits). Potential benefits range from cholesterol reduction to cancer risk prevention. Their use in weight loss programmes is already widespread and likely to expand further.

3.3 Flavourings To impart the characteristic flavour of flavouring e.g vanilin to give the flavour of vanila to ice cream. To increase, complement or modify flavour e.g vanilin to modify the flavour of chocolate or cocoa To mask the original flavour e.g anise to cover bitter medicinals

3.4 Acidulants Compounds that can serve as buffers, acids, alkalis & neutralizing agents The degree of acidity is an important factor in the processing and preparation of many foods The pH of foods may affect their colour, texture & flavour.

Acidulants Examples: Citric acid, phosphate – to acidify foods, e.g fruit juices, jams, jellies, carbonated beverages – minimizing heat processing requirements & limiting the growth of toxin-producing bacteria Sodium bicarbonate – leavening agent in baking powders

3.5 Colourants The phase “We eat with our eyes” is trite but true! Before food is tasted, before a single bite is even taken, the quality of that food is judged by how it looks! Usually the primary attributes consumers consider in making purchasing decisions. For fresh fruits and vegetables, for examples, colour is an indication of taste and flavour quality: e.g freshness, over-ripeness or under-ripeness

3.6 Antibrowning agents To retards enzymic browning – caused darkening in fruit juices, dried fruit & vegetables, frozen prawn, etc Addition of vitamin C, citric acid or sodium sulphite will interfere with dark colour pigment formation Sulphur dioxide – used in fruit juices, dried fruits.

3.7 Dough conditioners To modify protein & starch in cereal-based foods – result in improved properties such as reduced mixing time & increased loaf volume To produce more uniform bakery products with good crumb texture Examples: Various phosphates Sulfates Enzymes

3.8 Humectants Humectants aid in the retention of moisture and prevent the drying out of certain types of confections and of shredded coconut. Examples: Inclusion of propylene glycol to shredded coconut to keep it moist, E.g. Glycerine, Sorbitol

3.9 Curing agents The pink colour of cured meats is developed and fixed by the addition of small amounts of sodium nitrite. The nitrite also inhibits the activity of Clostridium botulinum which may be present in the meat. Carcinogenic substances called nitrosamines may be produced when nitrite combines with secondary amines under appropriate conditions. For this reason, the level of nitrite in cured meats can be carefully regulated.

3.10 Anticaking agents To prevent caking, lumping & agglomeration during storage It is added to dry ingredients such as salt, powdered sugar, finely ground spice blends Examples: Calcium silicate in salt mixtures

3.11 Firming agent To maintain desirable crispiness / texture in various food systems Examples: Alum is used in pickles Various calcium salts are used to maintain firmness in canned whole tomatoes Alum

3.12 Sweeteners Sugars, hydrolysed starches, and also a number of chemical compounds are found to have sweetening properties. Nutritive sweeteners – defined as products that have > 2% of the caloric value of sucrose per equivalent unit of sweetening capacity, e.g. high fructose corn syrup (HFCS) which is used as a replacement for sucrose in carbonated beverages.

Sweeteners Nonnutritive sweeteners – Naturally occurring or synthetic compounds that have elevated sweetening power compared to sucrose. e.g. saccharin, cyclamate, aspartame, stevioside It is used in low- or reduced- calorie foods

3.12 Preservatives Preservatives are substances capable inhibiting, retarding or arresting the growth of microorganisms Preservatives protect microbial growth with public health implications, whether of pathogenic bacteria which cause food poisoning (e.g salmonella), or certain moulds which form mycotoxins (e.g aflatoxin).

Preservatives Examples: Sodium benzoate – used in margerine, soft drinks Sulphur dioxide – used in fruit juice, dried fruits Calcium propionate – mould and rope inhibitors in bread

4. Food safety in Malaysia Legal Mandate: Food Act 1983 gazetted on 10th March 1983 Food Regulations 1985 gazetted on 26th September 1985 Enforced together on 1st October 1985 ERT 426 Food Engineering BBLee@UniMAP

Food safety in Malaysia Definition under Malaysian Food Regulations 1985 Any safe substance that is intentionally introduced into or on a food in small quantities in order to affect the food's keeping quality, texture, consistency, appearance, odour, taste, alkalinity, or acidity, or to serve any other technological function in the manufacture, processing, preparation, treatment, packing, packaging, transport, or storage of the food, and that results or may be reasonably expected to result directly or indirectly in the substance or any of its by-products becoming a component of, or otherwise affecting the characteristic of, the food, and includes any preservative, colouring substance, flavouring substance, flavour enhancer, antioxidant and food conditioner, but shall not include nutrient supplement, incidental constituent or salt.

4.1 GRAS Substances Many food additives are classified as GRAS (Generally Regarded As Safe). Additives are classified as GRAS when they have been used without apparent harm for long periods, long before regulations were put into effect. Example of GRAS substances: acetic acid, alum, ascorbic acid, baking soda, benzoic acid, caffeine, calcium citrate, corn starch, sugar, salt, monoglycerides, lactic acid, lecithin