FURAN UPDATE-LATEST RISK ASSESSMENT

There are increasing concerns among the consumers regarding the safety of many processed food products they consume every day. In many wealthy countries processed foods form more than 80% of their daily diet and it is easy to comprehend what would be the consequences if unsafe foods are ingested day in day out. While most concerns are based on the food industry practices of using hundreds of chemicals while manufacturing or cross contamination of foods with deadly bacteria and mold, there is also grave apprehension regarding the potential health damage some of the artifacts generated during processing can cause. Recent focus on such chemicals like acrylamide, polycyclic aromatic hydrocarbons, benzene and furan is because of the above concerns. 

Furan is not a new chemical discovered as it was known for ages and lot of studies regarding its synthesis and properties have been published. Furan and its derivatives are naturally occurring compounds found at very low levels in many foods and drinks and their association with the typical flavor of many foods is well known. They are a major class of compounds formed during the Maillard reactions and under pyrolytic conditions. Ascorbic acid and related compounds and Maillard type systems containing amino acids and reducing sugars, lipid oxidation of unsaturated fatty acids or triglycerides and carotenoids all contribute to formation of Furan during processing. Ionising radiation on the Furan formation in apple and orange juice products as well as in model systems has also been reported. Of course these basic knowledge did not raise much concern earlier but their detection in many industry processed foods became a matter of speculation regarding their effect on human health.

What is new is the detection of Furan in some foods using sophisticated analytical techniques in 2004 which raised some alarm regarding its impact on human health. It is rather surprising that a simple hetero cyclic organic compound like Furan with a 5-membered aromatic structure, made of 4 carbon atoms and an oxygen atom, can be a potentially toxic artifact capable of causing harm to human beings. Furan should not be confused with Furans, a separate category of chemical compounds broadly called Chlorinated di benzofurans coming under Dioxins. They however do not occur in any foods and hence not of much concern to the food industry as of now. According to International Agency for Research on Carcinogens, Furan is considered a carcinogen in human beings though evidence is yet to emerge with studies using human subjects.

Of a number of food samples from the industry analysed by the US Authorities, occurrence of Furan was confirmed in all products in concentrations in the range of 3 parts per billion (ppb) to 112 ppb. Almost all these products are either canned or bottled having undergone the sterilization process at high temperatures. Interestingly products containing sweet potato as a component invariably showed higher levels of Furan. Also Coffee, meat soups, stews, Chilli are other major sources of Furan. One redeeming feature in this scenario is that Furan is highly volatile and due to this furan is easily analyzed using a head space or SPME coupled with gas chromatography-mass spectrometry. Furan is rapidly and extensively absorbed from the intestine and the lung. It can pass through biological membranes and enter various organs.  Experiments have shown that furan is carcinogenic to rats and mice, showing a dose-dependent increase in hepatocellular adenomas and carcinomas, though preliminary exposure data suggest that the levels of Furan found in foods are well below the levels that would cause harmful effects.

What is the consumer to make out of these startling revelations? Probably sufficient data still do not exist to try for a zero tolerance level of Furan in foods though efforts are being made to find more about the safety aspects of this chemical. Since Furan is highly volatile normal open pan cooking and vigorous stirring can be expected to expel most of it through evaporation. A safe guideline is not to consume foods found to be very rich in Furan  and for maintaining good health consumer is well advised to eat a balanced diet, choosing a variety of foods that are low in trans-fat and saturated fat, and rich in high-fibre grains, fruits, and vegetables. Of course this easier said than done!

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

GLOBAL WARMING AND THE BASMATI RICE- INDIA TO LOSE DOMINANCE?

Here is a dooms day prediction by some agricultural scientists in India regarding the catastrophic consequences of global warming on Indian export of its much vaunted Basmati Rice. On the face of it the logical deductions made by them appear to be worth considering seriously. According to their assumptions, one of their failed experiments in the past had to encounter temperatures higher than normal for the season which probably could have resulted in reduced length of the grain and lower levels of the typical aroma.

According to them their experiment indicated a definite influence higher environmental temperature could have on the fragrance of this rice variety besides affecting its length. The crop obtained in their experiments did not grow long enough and was not as fragrant as it should have been when cooked. Temperatures during that year crossed 26 degree Celsius in September when the basmati flowers and, 15 to 20 days later, when the grain begins to fill out, because of which a shriveling of the grain was seen. The extra heat, it was hypothesized, prevented the food stored by the plant from travelling to the grain. Consequently, it failed to grow to the right length. The heat also could have destroyed fatty acids stored in the grain which give the basmati its distinct fragrance when cooked. Though more than 3 years have lapsed since this finding no field studies have yet been done so far by the agriculture scientists in ICAR the premier research agency in the country.

Basmati rice is a priced commodity of India with 80% of the world trade controlled by it. According to the authentic report of APEDA the vested authority that controls food exports from India, the export during 2009-10 was 2.01 mt valued at Rs 100 billion. It is a matter of pride for India that Basmati is the only commodity from the country being exported to more than 110 countries around the world. While rice exports suffer from time to time depending on production and local availability of this staple in any given year, Basmati export has enjoyed a steady growth over the years due to expanding areas of cultivation and steady policy of support and encouragement from the government.

It was in 1997 that India had the shock of facing a crisis in its Basmati monopoly when a private player in the US sought patent rights for the name Basmati claiming that it has developed a better variety through genetic improvement. Fortunately sustained efforts by the government and the agricultural scientists in fighting this threat resulted in not granting any patent rights to that party. The loss to India and Pakistan which enjoy almost 100% monopoly as far s Basmati is concerned would have suffered grievously if the patenting attempt of the American developer were to succeed.

There are more than two dozen varieties.of Basmati being grown in India that include Dehradun, Safidon, Haryana, Kasturi, Pusa, Ranbir, Suganda etc all being long grains with typical flavor due to presence of the volatile fragrance fraction 2-acetyl-1-pyrroline. There are also varieties designated with numbers and some of the popular ones are 198, 217, 370, 385 and 386. Though Basmati rice is more known for its scent, it is also a good cooking variety capable of retaining its texture without getting mushy. Besides it is a medium GI grain with a range of 55-65 that can ensure uniform release of glucose after consumption. The reported effect of global warming if confirmed by field studies under controlled conditions must be taken seriously and appropriate pre-emptive action must be considered to prevent any damage to India's long term strategy of retaining supremacy in this area. If warmer temperatures can affect Basmati varieties, what about its effect on normal rice strains? Will the yield go down or will there be change in the nutritional and eating qualities of normal rice? Answers must be found for these questions as India cannot afford to let any uncertainty affect its staple cereal on which millions of its population depend.

V.H.POTTY

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

NATURAL MALTING VS ENZYME MEDIATED MALTS

The technology of malting involves soaking of the grains, sprouting under high humidity conditions, drying and processing to remove the vegetative parts. Grain legumes and cereals are generally sprouted for preparing malted products. While green malt preparations are rich in enzymes used in the production of brewed alcoholic beverages, the kilned version is more commonly made for the food industry as a flavor ingredient in various foods like beverages, breakfast cereals, bakery goods etc. Barley is the most commonly used cereal since it has characteristic flavor and produces high levels of various enzymes on germination, ideal for getting good quality products. Some of the important enzymes produced during sprouting include alpha-amylase, beta-amylase, alpha-glucosidase, limit dextrinase, endopeptidase and endo-beta glucanase.

The malt desired for many applications is generally kilned at lower temperatures of about 60-65C while that demanded by distillers goes through a higher temperature of 85C. The pale malt has higher enzyme activity while dark malts contains only about 30% of the original enzyme activity. When malt is used for yeast fermentation, the sugars generated provide energy while the hydrolyzed protein products, as a result of the protease reaction, support yeast growth to produce alcohol. Beta glucanase enzyme modifies the insoluble polysaccharides into smaller molecular weight soluble components that helps to increase the viscosity very significantly. Beer products are valued for their color, flavor, bitterness derived from hops, viscosity and frothiness. Hard liquors like brandy and whiskey are made by distilling the alcohol produced during yeast fermentation and volatile constituents that come along with the alcohol give them their characteristic flavors

Manufacture of malt extract, an important flavor material for food industry is made from malted cereals. The combined malt amylolytic enzymes convert the insoluble starch present in the cereal into dextran and maltose while proteolytic enzymes hydrolyze proteins into peptides and amino acids. Aqueous extract so obtained is evaporated to get a viscous mass with about 78-80% solids. Spray drying yields malt extract powder or dry malt extract which will not contain any enzyme activity. In contrast dry malt obtained after sprouting, removal of sproutings, drying and coarse grinding under low temperature conditions, possess the characteristic enzyme activity so necessary for the liquor industry. Dextrin malt, caramel malt and black malt are made by heating to different extent and they have 53-63% reducing sugar, mainly maltose and 4.5 to 5.6% protein substances. Diastatic malt products like malt syrups have 60-72% reducing sugars and 1.8 to 3.5% proteins besides varying enzyme activities. Malt extract and syrups find use in more than 100 different food products including ice cream, baked goods like bread, biscuits and crackers, icings and fillings, malted milk and pastry.

As the malting operations involving several steps extending over at least 3-4 days for a batch to be completed, industry is severely handicapped in raising the productivity to meet the rising demand. The challenge is to make the process continuous and though technically it should be possible, the investment requirement will be astronomical while infrastructure requirement is mind-boggling. One of the alternate options available is to evolve a process that will use industrial enzymes commercially available to imitate the natural changes characteristic of natural malting. All enzymes identified as involved in malting like alpha and beta amylases, peptidases, beta glucanase and others are commercially produced by several internationally reputed biotech companies. Already some manufacturers of liquors have been able to reduce the barley needs for breweries by 70% using commercial enzymes and save considerably on time and cost. Biochemical engineers have studied the reaction kinetics of these enzymes and optimal working conditions are already well known. Continuous bio-reactors of different capacities with precise control of reaction conditions, are available to day and malt preparations of various specifications can be made continuously using them.

V.H.POTTY
http://vhpotty.blogspot.com/