Chemical compositions and antioxidant capacity of by-products generated during the apricot kernels processing

The compositions and antioxidant capacity were investigated about the by-products (blanching water concentrate (BWC) and debitterizing water concentrate DWC) produced during the industrial processing of apricot kernels, to evaluate the by-products' potential utilization. The results indicate that the by-products contain a great number of compounds like amygdalin, protein, phenolics, and flavonoids. Among them, the amygdalin has the highest content both in BWC and DWC, which is 33.480.04 and 23.89 +/- 0.03 (g/100g dry base weight), respectively. Furthermore, the by-products exert good antioxidant functions including the higher reducing power and radical-scavenging capacity on the 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and hydroxyl radicals, which is mainly attributed to the phenolic compounds, not the highest content of amygdalin by the principal component analysis and verification test of DPPH radical-scavenging capacity. In conclusion, the by-products definitely have great potential for utilization and should be recycled from the wastewater in the apricot kernels processing industry, especially for amygdalin.