b) By- products
During the processing of mango, peel and stone are generated as waste (40 to 50 percent of
total fruit weight). They are rich in various nutrients and value-added products could be
obtained from them. Good quality jelly grade pectin (6.1 percent) and edible fibre (5.4
percent) could be extracted from ripe mango peel. Acceptable quality vinegar (5.2 percent
acetic acid) and citric acid (20 g/kg peel) could be obtained from mango peel through
microbial fermentation. Mango peel having low protein value (3.9 percent) is a poor quality
animal feed. The peel could be protein enriched more than five times (20 percent) by solidstate
fermentation using Aspergillus niger. Mango peel has lignocellulosic composition and
hence its complete break down is difficult. It's co-composting with cow dung in 3:1 ratio
results in its successful biodegradation.
Mango kernel contains high amounts of fat and starch. The oil extracted from kernel is of
good quality and could be used in cosmetic and soap industries. The kernel flour (starch) after
MANGO: Post Harvest Operations Page 29
mixing with wheat or maize flour is used in chapaties in India. About ten per cent alcohol
could be obtained from mango kernel by co-culture fermentation. In food processing
industries, various enzymes are invariably used for pulp liquefaction, juice clarification, etc.
Enzymes such as cellulase and pectinase from mango peel and amylase from mango kernel
could be produced by microbial fermentation.