Effect of heat treatment on total phenolic and anthocyanin contents as well as antioxidant activity of the extract from Aspergillus awamori-fermented black soybeans, a healthy food ingredient.
Aspergillus awamori-fermented black soybeans, a healthy food ingredient, were subjected to heating at 40-100 degrees C for 30 min. After heat treatment, the methanol extract of the fermented black soybeans was examined for antioxidant activity including the 2,2-diphenyl-1-picryl-hydrozyl radical-scavenging effect and the Fe(2+)-chelating ability. It was found that antioxidant activity exerted by the methanol extract was stable with heating at a temperature up to 80 degrees C for 30 min. The extract showed a reduced antioxidant activity after heating the fermented black soybeans at 100 degrees C for 30 min. However, it showed approximately 70% and 40%, respectively, of the original 2,2-diphenyl-1-picryl-hydrozyl radical-scavenging effect and the Fe(2+)-chelating ability. Heating also reduced the total phenolic and anthocyanin content in the fermented black soybeans, but this reduction did not coincide closely with the reduction of antioxidant activity observed.
Lin
Yi-Ching
YC
Graduate Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan.
Chou
Cheng-Chun
CC
D000872:Anthocyanins / Q000032:analysis*; D000975:Antioxidants / Q000032:analysis* / Q000494:pharmacology; D001230:Aspergillus / Q000378:metabolism*; D005285:Fermentation; D006358:Hot Temperature; D010636:Phenols / Q000032:analysis*; D010936:Plant Extracts / Q000494:pharmacology*; D013025:Glycine max / Q000737:chemistry*
D000872:Anthocyanins; D000975:Antioxidants; D010636:Phenols; D010936:Plant Extracts