Saturday, December 5, 2009


That the scientists, big and small, cannot resist photo-ops for getting easy fame is borne out by many sensational development news which later turn out to be a damp squib. Incomplete development, half baked technologies, recycled past works and fictitious patents are becoming a part of the scientific world and their credibility is at its lowest ebb to day. In India one can see even the heads of R & D agencies vying with each other to project themselves as super achievers based on R & D works of their colleagues which are still incomplete with questionable claims. Here is the latest example of an Indo-American scientist claiming to have developed technology for making bread and biscuits from cotton seed flour and predicting that cotton seed flour would be available in the market in 10 years, sufficient to feed 500 million people!

It is known that cotton linters, the short fibers, covering the seed coat is used by the ice cream industry as a source of cellulose but it is limited to a minuscule of the industry that makes specialty health foods. Cotton seed is a major by-product during the processing of cotton into textiles and for every kg of cotton fiber extracted 1.6 kg of seed is obtained. Cotton seeds are a good source of edible oil, about 21% and moderate quality protein, about 23%. If world has not seen proper exploitation of this material as human food, it is due to the presence of a toxin by name gossypol in the seed which can harm the liver and the heart in humans, if consumed. Gossypol, a polyphenol compound, also affects non-ruminant animals precluding the use of cotton seed or its flour in most types of animal feeds.

About 4 decades ago a physical process ( Dorr Oliver Process), more popularly known as Liquid Cyclone Process (LCP), was developed to remove gossypol from cotton seed flour without affecting the quality of proteins present and a commercial unit was established in Hubli, Karnataka which could not take off due to poor demand from the food processing industry. Even the interest evinced by the Food and Nutrition Board of GOI to use gossypol free cotton seed flour as a protein source in foods developed for applied nutrition programs could not translate into any practical application. Availability of other de-oiled seed flours from soybean and groundnut at lower price did not help the cause of cotton seed flour at that time. But the attractive color, an acceptable nutty flavor and relatively high protein content can still make cotton seed flour and its concentrates a good ingredient for food industry provided it is freed from gossypol. But it can be only as a supplementary source, being deficient in Lysine and Methionine, the two essential amino acids human body cannot make.

Bt Cotton varieties which have become popular in some countries are reported to be gossypol free but the genetically modified versions do not find favor as far as food use is concerned. Incorporation of the boll worm killing gene into the seed makes it a suspect candidate for use in foods. But major cotton producers that include China, India, the US, Uzbekistan and Brazil have adopted Bt Cotton probably because of its high yield potential. In the US same volume of cotton is produced to day from one third of the land that was cultivated two decades ago. Of course the world production of cotton estimated at 25 million tons can yield about 3 million tons each of proteins and oil. Gossypol is now being investigated for its properties to counter act malaria, as a contraceptive and development of anti-cancer drugs and such an approach if succeeds can make the technology for edible cotton seed flour more viable.

There are international specifications for edible grade cotton seed flour with upper limits prescribed for gossypol. Regarding the claim that bread, biscuits, break fast cereals, pancakes, etc can be made using blends of cotton seed flour and wheat or corn flour, it may be technically feasible but to make the products acceptable to consumers may not be that easy. While technologically cotton seed flour of edible grade can be made as per standard specifications, the cost factor may still hamper its widespread use by the industry in the foreseeable future, even if acceptable food products are developed.


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