Effect of gamma irradiation and cooking on physical, chemical and sensorial aspects in soybeans cultivars with and without lipoxigens.

Abstract

The soy is a vegetable with high nutricional value, mainly because its high proteic content. Amongst the culture of grains, the soy characterizes itself as most important of the country, what represents a bigger incentive for the consumption of this food. However, a great claim of occidental consumer is its characteristic odor and flavor, known as “beany flavor”, that is proportionated for the enzyme lipoxigenase. The catalytic action exerted by this type of isoenzim on fat acid polyunsaturateds, linolenic acid and linoleic acid of the soy grains is one of the main responsible factors for the appearance of the carbons composites, which cause the ackward flavor in grains. To improve the organoleptics characteristics of soy, researchers had developed new cultivars, without the presence of lipoxigenase. The objective of this work will be to evaluate soybeans free of lipoxigenase in relation to its sensorial, physics and chemists aspects and, comparing the results with soybeans that contain lipoxigenase. The grains used will be to developed and supplied from Embrapa. The physical analyses will be: time of cooking and time of hydrating of the grains. The chemical analyses are: centesimal composition, protein digestibility, antioxidant activity of soybeans (DPPH e ABTS), isoflavons and anti-nutritionals factors, as: total phenolics, tannins, and tripsin inhibitors. Sensorial analysis will be carried through, applying analytical methods of differentiation for election of provers, and descriptive method to measure the quality of the soy. The statistical delineation to be used will be factorial 2x2x4 (cultivars x cooking x doses) and, at the end, it will be analysis statistics for comparison and quarrel of the gotten results.