Sunday, September 19, 2010

THE FURAN SCARE-NEW SAFETY CONCERNS


Food industry is facing increasing risks in sustaining itself because of safety concerns sprouting up every day due to new discoveries and emerging knowledge in food science and toxicology. Never heard of chemicals such as Acrylamide have been in the news during the last one decade with no definite conclusions from the scientific community regarding the extent of threat perception posed by these newly "focused" chemical artifacts produced during processing. Unfortunately in spite of consistent efforts in several countries, Acrylamide, formed in many foods during thermal processing under low moisture conditions, has not been established as a threat to consumer safety. It may be recalled that Acrylamide was detected in many foods by Swedish scientists in 2002 and since then thousands of publications appeared, covering practically all aspects of this chemical. Those foods containing the amino acid Asparagine and high starches were found to generate Acrylamide under frying and baking temperatures, probably through the well known Maillard reaction route or the "browning" phenomenon. Though many scary stories emerged regarding its role in human cancers in nervous system, oral cavity, peritoneum, thyroid gland, mammalian gland, uterus etc, these claims were found to based on experiments in animals like mice using doses 900 times higher than possible exposure by humans through the industry produced food products like potato chips!

Food safety is a holy cow and it is very common to talk about the food safety, giving the benefit always to consumer activists who articulate such concerns. Logic is often thrown to winds when tall claims are made regarding safety of foods and ingredients that go into the food during its making. It is often forgotten that eating a food is always risky and such risks can come from processed foods as well as those cooked at home. Decision to ban a particular food has to be taken based on a scientific risk-benefit analysis and not on risk alone. Taking the case of Acrylamide itself, concerns regarding consumer safety are understandable, scaling up the tempo of opposition to fanatical levels is not all justified based on current evidence. Think about thousands of products consumed in India for centuries which were invariably prepared based on raw materials rich in proteins and carbohydrates and probably Acrylamide has been a part of these foods prepared under high temperature conditions for long duration. Baked foods have been in use in western countries since time immemorial and people have not been dying at alarming rate because of cancer. Modern analytical tools have made detection and quantification easier and more accurate but this does not justify raising unnecessary concerns regarding their presence in food.

Now comes a new scare that may rattle the industry further regarding the presence of a new set of chemical artifacts in processed foods and beverages called Furans which are reported to be capable of causing cancer and liver toxicity. Furans refer to a group of chemicals belonging to the group of dioxins and furans. The chlorinated dibenzo furans are implicated in toxicity in animal studies though the levels at which they were used in such experiments are very high. They are formed in foods during processing and being volatile can escape from the finished products by stirring or after a lapse of some time. Oxidation of poly unsaturated fatty acids and similar compounds, decomposition of ascorbic acid derivatives and some carbohydrates can contribute to formation of furans in many foods processed at temperatures beyond 100C. Furans provide typical aroma and taste in many foods and are present in products like roasted coffee powder, canned foods, infant foods, baby foods, puffed rice, fish products, meat products, tomato soups, milk products etc at low concentration levels. Ground coffee can contain Furans as high as 6900 ug per kg while in instant coffee it comes down to 602 ug per kg. Ready to serve coffee beverage can contain about 100 ug of Furans. They are relatively low in milk products like infant foods in the range of 3-40 ug per kg.

Between 2004 and 2009, sustained cooperation amongst some of the countries under a single project generated data on Furans in over 4000 samples belonging to 21 food categories. The reproducability of these data may be tricky because of the high volatility of these chemicals and the possibility of significant reduction of active levels during the interval between opening of the food pack and preparation of test samples. Similarly there can be significant changes in the levels of Furans between original products and preparation of ready to consume final product. It may be reassuring to note the stand of the USFDA which felt that Furans, at this stage does not warrant any concern and cannot be considered as a threat to consumer health. Similarly Canadian Health authorities have taken the stand that present level of knowledge does not call for any change in the dietary practices in that country because of furans in foods.

The million dollar question is whether there should be any concern at all in India where probably people consume foods which are over processed under high temperature conditions. If a product like condensed milk can contain furans at levels of 80 ug per kg, what would be the condition of products like khoa and khoa based products which are made by open kettle heating over long periods or a product like tomato puree made by concentration without vacuum. If poly unsaturated fatty acids are precursors, frying in oils from soy bean and others with high oleic, linoleic and linolenic acids content can contribute to generation of furans. As the information on Furans in Indan foods is not yet available, it may be worthwhile for an institution like National Institute of Nutrition at Hyderabad to look into this area for at least putting the issue at right perspectives.

V.H.POTTY

http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

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