Effect of antioxidants on the activity of lipoxygenase in soymilk
The soymilk is a nutritional beverage, inexpensive and easy to obtain. Currently, there are many studies relating the soymilk to their potential nutraceutical, resulting from the action of phytochemicals (isoflavones and proteins). However, the beverage is less consumed by western populations, due to rancid taste resulting from the action of the enzyme lipoxygenase (LOX) activated in the extraction process. Thus, the aim of this study was to evaluate the effect of antioxidants on the specific activity of lipoxygenase in soymilk produced from different soybean cultivars. For the processing of soymilk were used BRS-213, BRS-258 and EMBRAPA-48 cultivars, in proportion 1:6 (soybean: water). The natural antioxidant (tocopherol) and synthetic (TBHQ: tert-Butylhydroquinone) was added to soymilk for each cultivar. The soy milks were supplemented with three different amounts of antioxidants (minimum, intermediate and maximum). The maximum amount has been established from the standards set by ANVISA. There were 18 treatments with three replications, totaling 54 experimental plots. The maximum amount of tocopherol induced significantly (p≥1) greater reductions in the activity of lipoxygenase in soy milk the BRS-258 cultivar. However, there wasn’t difference between the amounts of TBHQ in reducing the activity of lipoxygenase in soymilk of BRS-258 and EMBRAPA-48 cultivars. It was concluded that both antioxidants induced reduction in the activity of lipoxygenase, but the tocopherol at its maximum amount achieved better results when compared with TBHQ.