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Gan Jia Jie , 2A4. Food Additives. Food additives are chemical substances added to foods to improve flavour , texture, colour , appearance and consistency. What are Food Additives ? (I). http://www.choice.com.au/reviews-and-tests/food-and-health/food-and-drink/safety/food-additives.aspx.
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GanJiaJie, 2A4 Food Additives
Food additives are chemical substances added to foods to improve flavour, texture, colour, appearance and consistency. What are Food Additives? (I) http://www.choice.com.au/reviews-and-tests/food-and-health/food-and-drink/safety/food-additives.aspx
Food additives may be natural or artificial. • Common natural additives include sugar, salt, corn syrup, baking soda, and pepper. • Many modern additives, such as vitamins and some flavours, are made in a laboratory but most of them are exact replicas of naturally occurring substances and the body is unable to distinguish between the natural and artificial forms. • Direct additives are those that are intentionally added to foods for a specific purpose. • Indirect additives are those to which the food is exposed during processing, packaging, or storing. Preservatives are additives that inhibit the growth of bacteria, yeasts, and molds in foods. What are Food Additives (II)
Food additives are substances intentionally added to food either directly or indirectly with one or more of the following purposes: 1. To maintain or improve nutritional quality 2. To maintain product quality and freshness 3. To aid in the processing or preparation of food 4. To make food more appealing 5. Control the acidity and alkalinity, and to provide leavening. Purpose of Food Additives
Colors Emulsifiers Flavorings Gelling agents Preservatives Sweeteners Anti-cake agents Antioxidants Acidulants Common Types of Food Additives
Color is commonly added to foods, for good visual appeal. • Food colors are divided into 3 main types: • Natural Colors • Nature Identical Colors • Synthetic Colors Colors
Natural Colors • These are obtained from natural sources such as grasses, leafy vegetables, fruit skins, roots and seeds of plants. • Animals can also be a source of food colourings. Cochineal, or carminic acid, is a red colour that is obtained from the bodies of certain scale insects. Beet Carmine Grape
The colors are exactly the same molecules found in natural sources but they are made synthetically. Nature Identical Colors Alchoholic Beverages Diary and Ice Cream Bakery Products
These are colors that do not occur in nature and have been made in a factory. They have been carefully tested to make sure that they are safe Synthetic Colors
There are two types of emulsions. An oil-in-water emulsion contains small droplets of oil that are dispersed in water. Alternatively, a water-in-oil emulsion has small droplets of water that are dispersed in an oil. They are used to aid in the processing of foods and also to help maintain quality and freshness. In low fat spreads, emulsifiers can help to prevent the growth of moulds which would happen if the oil and fat separated. Emulsifiers • The emulsifier keeps oil and water mixed. With out an emulsifier water and oil would be separate. Soy Based Emulsifier
The brain interprets signals from taste, smell and even vision before turning them into an impression of the food's taste. Different people will find different tastes nice or unpleasant. Flavorings are added to food products to give, enhance or intensify flavor. Foods may contain more than a thousand chemical compounds that contribute to their flavor. Flavorings
Gives shape and structure. Thickeners or thickening agents make foods thicker. Stabilizers help to maintain the physical and textural properties of foodstuffs through their production, transport, storage and cooking. Gelling Agents
The substances belonging to this group are high molecular weight compounds. They are usually proteins, such as gelatin, or complex carbohydrates like pectins , starches, alginates and gums. • Most are long chain molecules (polymers) that are made up of hundreds of linked units called monomers. • They can be divided into a number of categories depending on their source of origin. Gelling Agents
Food preservation is the procedure of treating and handling food to prevent or greatly slow spoilage (lack of quality, edibility or nutritive value) caused or accelerated by micro-organisms. • Most preservatives today are actually fungistatic in their action. That means they prevent the growth of fungi, molds and yeast. • They have little effect on bacteria but using a combination of preservatives, with antibacterial properties, can give food all round protection. • Food preservatives help to control the spread of bacteria which can cause life threatening illnesses such as salmonellosis or botulism. • There are mainly 3 types of preservatives: • Natural Preservatives • Artificial Preservatives • Chemical Preservatives Preservatives
Natural preservatives are considered safer by many because they have always existed in nature and our immune systems are used to them. Most of the preservatives that come from a plant source are safe for humans. • Popular Natural Preservatives • Neem Oil • Salt • Sugar • Lemon • Honey • Citric Acid • Bee Propolis • Rosemary Extract • Grapefruit See Extract • Potassium Sorbate • Alpha tocopherol (also known as vitamin E) Natural Preservatives
Artificial preservatives are a group of chemical substances added to food, sprayed on the outside of food, or added to certain medications to retard spoilage, discoloration, or contamination by bacteria and other disease organisms. • Artificial food preservatives can be divided into three major groups, antimicrobial agents, antioxidants and chelating agents. Artificial Preservatives
Chemical preservatives are added to food to keep them fresh and unspoiled during storage. • There are three classes of chemical preservatives commonly used in foods: • Benzoates (such as sodium benzoate) • Nitrites (such as sodium nitrite) • Sulphites (such as sulphur dioxide) Chemical Preservatives
Methods of Food Preservation http://www.understandingfoodadditives.org/pages/Ch2p5-2.htm
Provide texture in baked goods it stops them from drying out. Lowers the freezing point in ice creams Acts as a preservative in jams Strengthens "mouthfeel" in soft drinks Adds bulk to baked goods Sweeteners
Processed foods often contain ingredients that are mixed as powders. Anti-caking agents are added to allow them to flow and mix evenly during the food production process. They rarely have nutritional value and only a small proportion of the additives find their way into the food. Anti-caking Agents
Antioxidants are added to food to slow the rate of oxidation and, if used properly, they can extend the shelf life of the food in which they have been used. Spoilage of fat is called rancidity. All fat containing foodstuffs like nuts, breakfast cereals or potato chips have a tendency to become rancid. Antioxidants are added to these products to prevent rancidity. There may be health benefits from the use of antioxidants. Oxidation reactions in the body could be linked to the build-up of fatty deposits that cause blockages in arteries that can cause heart attacks. Antioxidants may be important in preventing this and there could also be a link with the prevention of certain cancers, arthritis and other conditions. Antioxidants
Acidulants are additives that give a sharp taste to foods. They also assist in the setting of gels and to act as preservatives. Common acidulates; acetic acid, citric acid, fumaric acid, lactic acid, malic acid, phosphoric acid, tartaric acid. Acidulates
1. Sodium Nitrate, Sodium Nitrite 2. BHA and BHT 3. PropylGallate 4. Monosodium Glutamate 5. Hydrogenated Vegetable Oil 6. Aspartame 7. Acesulfame-k 8. Food colorings: blue 1,2; Red 3;Green 3;yellow 6 9. Olestra 10. Potassium Bromate 11. White Sugar 12. Sodium Chloride Twelve Most Dangerous Food Additives
Food preservatives have to be safe for human consumption. • They can stop the food-decay microbes from growing but must not harm the cells of the human body. • There are also maximum levels of preservatives allowed, so that high concentrations of preservatives in food are not permitted. Are Preservatives Safe?
Usage of preservatives have to be regulated as excessive consumption pose health risks. Sulfur dioxide and sulphites are used in fruits, wines and dried fruits and vegetable, in order for these products to avoid turning to brown. But sulphites are linked with hyperactivity and it is not recommended for people who are suffering from asthma. Many food products use Butylated hydroxyanisole (BHA) and hydroxytoluene (BHT) as preservatives. But with these preservatives, it can cause tumors and cancer for their carcinogenic characteristics. Cholesterol imbalance, hyperactivity, asthma attack, and some other disorders are linked to products that use BHT as preservative. These are considered the two most dangerous preservatives. BHT is banned to several countries across the globe. Health Risks of Preservatives (i)
Benzoic acid which is added to sauces in food is linked to hyperactivity and also skin and eye irritations. Asthmatic people can not consume products with benzoic acid. It also can cause neurological problems. • Sodium Citrate is used in meat and baby food but also in personal care products. Large amounts can cause bladder tumors. However, Sodium Citrate is related to Citric Acid and is much safer than other synthesized food preservatives. • Tertiary butylhydroquinone (TBHQ) are added to fats, oils and margarine, so they are often found in snacks like chips. It can cause nausea and delirium. It is petroleum based. Not much information is available about this preservative and it has been referred to as the "mystery preservative“ and one which should be wary of. • Nitrates are used to bring up the flavor to a higher notch. Large use of nitrates is already fatal to one’s health. Nitrate is bad for the blood because it will be converted in the blood to form a harder substance that makes it really difficult for the blood to transport oxygen. Health Risks of Preservatives (II)