Hexanal Accumulation and DETBA Value in Homogenate of Soybean Seeds Lacking Two or Three Lipoxygenase Isoenzymes

Abstract

Soybean lipoxygenases are responsible for the generation of undesirable flavors which limit wide utilization of soybeans in food products. Lipoxygenase-lacking mutants are expected to be soybeans with improved flavors. In this study, the accumulation of hexanal and the 1,3-diethyl-2-thiobarbituric acid (DETBA) value in homogenates were determined from two normal soybean cultivars (L 123(S) and L 123(F) , three soybean cultivars with L-1 (L 1 ), L-2 (L 2 ), and L-3 (L 3 ), and one soybean cultivar lacking all three lipoxygenase isozymes (L 0 ). Hexanal accumulation in the homogenates was in the order L 2 >L 123(S) >L 123(F) >L 1 >L 3 >L 0 . The DETBA value in the homogenates was in order L 123(S) , L 123(F) >L 2 , L 3 >L 1 , L 0 . Such cultivar differences were induced after the soaked soybeans were ground or after the soybean flour was wetted. These results suggested that L 0 could become a superior soybean for food ingredients, concerning flavors originating from lipoxygenases