Is your fresh fish really fresh?
Food inspectors, regulators and even health-conscious consumers would soon be in a position to find out if the fish available in the market is free of contaminants
How safe is the fish available in the market? This question is especially relevant for fresh, but frozen, fish transported in ice-filled cartons from distant fish production centres. Most of it normally carries hazardous contaminants like formaldehyde and ammonia. Fish traders often use these chemicals to prolong the shelf life of fresh fish and hide the underlying spoilage. Formaldehyde delays deterioration of fish and helps retain, though deceptively, its fresh look to keep it in marketable state for an extended period. Ammonia slows down melting of ice and also conceals latent rotting of fish by preserving the bright red colour of fish gills and the shining appearance of fish skin to misguide the buyers about its freshness.
The International Agency for Research on Cancer, a wing of the World Health Organisation, has classified formaldehyde as carcinogenic for human beings with sufficient evidence of causing cancer of nasopharynx (upper part of throat behind the nose). Its use in food products is prohibited. According to scientists of the Cochin-based Central Institute of Fisheries Technology (CIFT), high content of formaldehyde in food can cause severe abdominal pain, vomiting, kidney ailments and, in worst cases, even death. Formaldehyde and its concentrated solution, formalin, are commonly used as disinfectants and also in the industries making plastics, paints and textiles. Though ammonia is not innately hazardous, its use in fish is deemed an unfair practice as it masks decaying of fish to mislead the consumers. “Monitoring studies conducted by research bodies have confirmed the presence of these chemicals in freshly marketed fish, its consignments in transit and also in the ice in fish containers,” says CIFT director C N Ravishankar. Intervention from food quality enforcement agencies is essential to stop these pernicious practices, he maintains.
To facilitate an on-the-spot detection of these impurities, CIFT has developed portable rapid testing kits that can give reliable indication of their presence in a couple of minutes. Named aptly as “CIFTest kits”, these cheap and easy-touse devices comprise special paper strips, reagent solution and a standard colour chart for comparing the results. All that needs to be done is to swab a paper strip a few times over different parts of the fish, put one drop of reagent over it and match the change in colour with the standard chart after a minute or two. Each test costs around ~2 at present. But, this cost would drop perceptibly when the kits are mass produced.
Considering that some fish dealers are also using another non-permitted preservative, sodium benzoate (of noodles adulteration ill-fame), CIFT is developing a detection kit for this additive as well. This institute has already been notified by the Food Safety and Standards Authority of India (FSSAI) as the national referral laboratory for quality assessment of fish and fisheries products.
Some CIFTest kits, fabricated in the CIFT laboratories, are already being used for demonstration and awareness creation. These have also been passed on to some fisheries-related state organisations and supermarkets in Kerala. Several other states, such as Tripura, Goa, Karnataka, Maharashtra and Tamil Nadu are said to have evinced interest in utilising these kits to check the use of formaldehyde and ammonia in fish preservation and transportation. CIFT does not intend to patent this technology. It would license it to prospective entrepreneurs for commercial production. The process of inviting expression of interest for this purpose is expected to start soon. Some companies are already in touch with the institute for getting the production rights.
Hopefully, food inspectors, quality regulators and even health-conscious consumers would soon be in a position to find out if the fish available in the market is free of contaminants. This would greatly help in curbing the tendency among the traders to use illegitimate preservatives to lend false look of freshness to fish. The fisheries and food departments of states would be well-advised to promote the use of these kits to ensure the availability of good quality, fresh and wholesome fish to the consumers.