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BIOLOGY
Biofortification – breeding crops with higher levels of vitamins and
minerals, or higher protein and healthier
fats – is the most practical
means to improve public health.
Breeding for improved nutritional quality is undertaken with the
objectives of improving –
(i) Protein content and quality;
(ii) Oil content and quality;
(iii) Vitamin content; and
(iv) Micronutrient and mineral content.
In 2000, maize hybrids that had twice the amount of the amino acids,
lysine and tryptophan, compared to existing maize hybrids were
developed. Wheat variety, Atlas 66, having a high protein content, has
been used as a donor for improving cultivated wheat. It has been possible
to develop an iron-fortified rice variety containing over five times as much
iron as in commonly consumed varieties.
The Indian Agricultural Research Institute, New Delhi has also released
several vegetable crops that are rich in vitamins and minerals, e.g., vitamin
A enriched carrots, spinach, pumpkin; vitamin C enriched bitter gourd,
bathua, mustard, tomato; iron and calcium enriched spinach and bathua;
and protein enriched beans – broad, lablab, French and garden peas.
9.3 SINGLE CELL PROTEIN (SCP)
Conventional agricultural production of cereals, pulses, vegetables, fruits,
etc., may not be able to meet the demand of food at the rate at which
human and animal population is increasing. The shift from grain to meat
diets also creates more demand for cereals as it takes 3-10 Kg of grain to
produce 1 Kg of meat by animal farming. Can you explain this statement
in the light of your knowledge of food chains? More than 25 per cent of
human population is suffering from hunger and malnutrition. One of the
alternate sources of proteins for animal and human nutrition is Single
Cell Protein (SCP).
Microbes are being grown on an industrial scale as source of good
protein. Microbes like Spirulina can be grown easily on materials like
waste water from potato processing plants (containing starch), straw,
molasses, animal manure and even sewage, to produce large quantities
and can serve as food rich in protein, minerals, fats, carbohydrate and
vitamins. Incidentally such utilisation also reduces environmental
pollution.
It has been calculated that a 250 Kg cow produces 200 g of protein
per day. In the same period, 250g of a micro-organism like Methylophilus
methylotrophus, because of its high rate of biomass production and
growth, can be expected to produce 25 tonnes of protein. The fact that