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Food Additives: Friend or Foe?

Author: Rachel Tan Choon Hui (Lecturer, UCSI University)

A wide range of processed foods are available in the market since the 19th century, and it has led to the growth in the production of food additives. At present, there are up to 25,000 food additives being used worldwide. Food safety risk is becoming a public concern and also a global problem. The abuse of food additives and the illegal use of chemical additives can pose negative effects towards human health. It can also cause serious threats towards a country’s social stability. Nonetheless, food additives are crucial in food processing. Without additives, salad dressing and mayonnaise would separate into oil and water phases and become rancid. Besides that, bread would quickly mold and baked products cannot achieve the leavening effect.

Food additives are substances that are added into food products either intentionally or accidentally. Intentional additives are substances that are purposely added and become parts of a food product like sugar, salt, baking soda, citric acid, and vegetable colouring. Indirect additives are contaminants that accidentally get into a food product during production, processing, or packaging. Examples of indirect additives are antibiotics, dirt, dust, hair, hormones, and insects. These contaminants are highly undesirable and thus, the occurrence of such accidental additives should be restricted to a minimum level.

Food manufacturers utilize food additives for many reasons. Firstly, additives are added to improve or maintain nutritional value of a food product. Most of the time, nutrients are lost during food processing especially those that involve heat treatment. Therefore, foods like milk, margarine, and cereals are enriched or fortified by additives like vitamins A and D, iron, riboflavin, and folic acid. Enrichment means the addition of nutrients lost during processing in order to meet a specific standard for food. Fortification implies the addition of nutrients, either absent or present in insignificant amounts. Vitamin A, iron, zinc and iodine deficiencies are global problems, affecting at least 30% of the world population. The manifestations of such micronutrients deficiencies are vitamin A deficiency syndrome, anemia and goiter. Hence, food fortification is essential to reduce the occurrence of deficiencies.

Secondly, additives like antimicrobial agents and antioxidants are added to prolong the shelf life of foods. These substances act as preservatives that stop or delay nutritional losses due to microbiological, enzymatic or chemical changes of foods. Antimicrobial agents inhibit the growth of bacteria, yeasts, and molds. For example, sorbic acid, sodium benzoate and potassium benzoate are commonly used in many kinds of foods, such as, marinated fish, fruit-based fillings, jam, and salad cream. Canned seafood or canned fruits normally do not require the addition of preservatives. This is because these products are sterilized at a temperature that is high enough to kill all microorganisms. Besides that, the presence of salt, vinegar or sugar can act as natural preservatives.

On the other hand, preservatives may be added in canned food that contains high fat content. Oils and fats are susceptible to oxidation upon storage, which will result in product rancidity. For this reason, antioxidants like BHA1, BHT2, ascorbic acid, and tocopherols are added into foods to slow down the oxidation of fats as well as pigments. Curing agents, which is a preservative such as sodium nitrite, is used in meat products to help retain the pink colour of cured meats. It can also prevent the growth of bacteria, reduce the rate of oxidation and enhance the taste in refrigerated meat. For the past few decades, the effects of nitrite and nitrate on human health have been questionable among consumers. The ongoing research focused on the metabolism of nitric oxide, nitrite, and nitrate appears to reaffirm the general benefits of nitrate/nitrite in human health. Yet disagreement about health impacts of dietary nitrite and nitrate, particularly in cured meats still exists despite changes in meat curing practices that minimize potential for nitrosamine formation.

The appeal of colour is a major influence on consumer perception and food acceptability and preference. Colour can even affect the way we perceive flavour! For instance, when we buy mango flavoured candy, we expect it to be yellow in colour. If it is blue or in any other colour, most of us would not even consider buying it. Thus, food processors include colorants in foods to impart desired colour. Food colours can be synthetic or obtained from natural sources that are plant, animal, or mineral origin. These colourants must meet certain legal criteria for specifications and purity.

Another food additive that is added into food is flavouring, which makes food more appetizing to meet consumers requirement. Natural essential oils from plants (e.g. herb and spice) are used as flavourings. Examples of natural flavourings include vanilla, ginger, peppermint, cinnamon, and cherry. Food industry also utilizes synthetic flavourings that resemble natural flavours. Sometimes commercial flavour extracts are blends of natural and synthetic flavourings. One of the most common flavour enhancer in the market is Monosodium glutamate (MSG). MSG is the sodium salt of the non-essential amino acid glutamic acid. MSG provides the fifth taste – Umami, besides sweet, salty, sour and bitter.

Umami, a Japanese word, means savoury or delicious. The effects of MSG on human health remain controversial. According to a research conducted by Nakanishi and colleagues (2008), MSG is associated with liver inflammation and dysplasia. Other research showed that MSG causes potential health risk like headaches, numbness, flushing, muscle tightness or even bronchoconstriction in some asthmatic individuals. However, Food Standards Australia New Zealand (FSANZ) carried out a safety assessment of MSG and concluded that there is no convincing evidence that MSG is a significant factor in causing systemic reactions resulting in severe illness or mortality.


Vanilla extract from vanilla plant can be used to produce food products like ice cream, coca-cola. (Adapted from http://www.topfoodfacts.com/?p=1928 )


Food additives are used to maintain or improve the quality of food. The majority of direct food additives fall into the category of Generally Recognized As Safe (GRAS). These additives are vital for the production of many foods to meet consumers’ expectations. They also help to overcome malnutrition problems in many countries and prolong product shelf life. Unscrupulous food manufacturers who violate the use of food additives to deceive and disguise are unacceptable. Food manufacturers should abide with the law and be ethical in choosing the right food additive for food production and at the right amount.

References:
Akhtar, S. Anjum, F.M., Anjum, M.A. (2011). Micronutrient fortification of wheat flour: Recent development and strategies. Food Research International 44: 652-659.

Murano, P.S. 2003. Understanding Food Science and Technology. USA: Thomson Learning, Inc.

Nakanishi, Y., Tsuneyama, K., Fujimoto, M., Salunga, T.L., Nomoto, K., An, J.L., Takano, Y., Iizuka, S., Nagata, M., Suzuki, W., Shimada, T., Aburada, M., Nakano, M., Selmi, C. and Gershwin, M.E. (2008). Monosodium glutamate (MSG): A villain and promoter of liver inflammation and dysplasia. Journal of Autoimmunity 30: 42-50.

Parker, R. (2003). Introduction to Food Science. USA: Delmar, Thompson Learning.

Sindelar, J.J., Milkowski, A.L. (2012). Human safety controversies surrounding nitrate and nitrite in the diet. Nitric oxide 26: 259-266.

Wu, L.H., Zhang, Q.Q., Shan, L.J., Chen, Z.X. (2013). Identifying critical factors influencing the use of additives by food enterprises in China. Food Control 31: 425-432.

Zengin, N., Yüzbaşioğlu, D., Ünal, F., Yilmaz, S. and Aksoy, H. (2011). The evaluation of the genotoxicity of two food preservatives: Sodium benzoate and potassium benzoate. Food and Chemical Toxicology 49: 763-769.

Web reference:
http://foodsafety.govt.nz/elibrary/industry/Monosodium_Glutamate-Science_Research.pdf

Notes:
1 Butylated Hydroxyanisole
2 Butylated Hydroxytoluene