Effects of microwave pretreatment on the content of cyanogenic glucosides in pressed flaxseed cakes and the quality of pressed oil

The parameters of microwave pretreatment applied in lowering cyanogenic glucosides of pressed flaxseed cakes were optimized,and the quality of pressed Gansu flaxseed oil before and after being treated under the best condition of microwave treatment was compared.Moreover,the effects of lowering cyanogenic glucosides in other five different varieties of pressed flaxseed cakes under the optimal condition of microwave treatment were compared.Results showed the optimal condition of microwave pretreatment was established : power 700 W,time6 min,flaxseed moisture 17%.Under the optimal condition,the content of cyanogenic glucosides in pressed Gansu flaxseed cakes was reduced to( 4.18 ± 0.23) mg / kg.The acid value of pressed Gansu flaxseed oil was significantly increased,while peroxide value was decreased.Meanwhile,the yellow value and red value were also increased.But fatty acid composition,the content of sterols had no significant changes,total phenols content was 1.42 times as the phenols of directly pressed flaxseed oil.In addition,the cyanogenic glycosides content in pressed Haerbin flaxseed cakes was( 15.40 ± 0.47) mg / kg,but cyanogenic glycosides content in other four different varieties of flaxseed cakes all remained lower than 5 mg / kg.