Abstract: |
Fruits, being highly nutritive, are
important component of human diet but they possess very short post-harvest
shelf life. As ripen, they become very soft and more prone to injuries, which
makes them highly perishable. In India, over 30% of the annual
produce is wasted due to spoilage. Hence, there is an urgent need to develop
technologies to overcome post-harvest losses of fruits. Physiologists and
biochemists attempted to extend the shelf life of fruits by different means
though the results were not very satisfying. It was demonstrated recently that
a judicious dose of g-irradiation
(0.1-0.5 kGy) could enhance the shelf life to fruits by about a week to a
fortnight, which could help in minimising the spoilage during storage and
transportation. However, stringent quality controls have to be strictly
followed to get the best results. Studies revealed that g-irradiation brings alterations/changes in metabolic pathways, which
delay the production of essential precursors and energy required for ripening
of fruits. Another strategy, to enhance the shelf life of fruits, could be
adopted through regulation of endogenous ethylene production. Most recent
studies have shown that it could be achieved by such genetically modified (GM)
crops where gene expression of key enzymes responsible for ripening, like
PG-ase, EFE and ACC-synthase, by means of antisense RNAs. However, adoption of
this technology has so far been deterred due to apprehensions of safety issues
associated with GM crops. An alternate method for prevention of spoilage of
fruits as well as sustaining the interests in farmers could be the value
addition of fruit commodities. This could be achieved by improving the conventional
methods as well as development of non-conventional products of commercial
interest. Nuclear Agriculture and Biotechnology Division, BARC has developed
processes for the production of juice and powder from ripe banana, the largest
produced and maximum wasted fruit, by creating an in-built mechanism to
inactivate the pectin forming enzymes. With this process, over 60-80 % of the
total moisture of the fruit is extracted out as juice. The commercially
available variety, ‘Harichal’ (Mumbai kela) could give juice 550-640 ml /kg
pulp. It is also demonstrated that a number of products of commercial
significance, like banana nectar, carbonated juice and wine, from banana juice
and biscuits, cakes, milkshakes, etc. from banana powder could be developed.
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