Effect of frying media and packaging materials on shelf life of tengolalu-a deep fat fried snack

Tengolalu an Indian deep fat fried snack was prepared by frying in four different refined vegetable oils,
Coconut oil, Palm oil, Ground nut oil and Sunflower oil. This was packed in two packaging materials 75μ
polypropylene and 12μ metallised polyester/50μ HDPE-LDPE which varied a lot in their oxygen
transmission. The products were exposed to 30-40% RH and 38-40°C. The products were subjected to
physico-chemical and sensory analysis during periodic withdrawals of every 10 days. Sunflower oil,
Ground nut oil, Palm oil and Coconut oil could offer <20 days, 30 days, 40 days and 60 days shelf life
respectively. Increase in peroxide value and rancid odour terminated the shelf life. The shelf life was in
commensuration with degree of unsaturation of oils. For this dry product, hydrolytic rancidity which is
predominant in saturated oils like Coconut oil was not observed up to 60 days of storage period
studied.