Effects of Nitrogen Sources and Inorganic Salts on Antioxidant Activity of Goat Milk Fermented by Lactobacillus plantarum L60

Abstract This study investigated the effects of various nitrogen sources (peptone, casein hydrolysate) and inorganic salts (KH2PO4, MgSO4 and NaCl) on the antioxidant activity (specifically, DPPH and superoxide anion scavenging rate), acidity, and pH of peptides in goat milk (GM) fermented by Lactobacillus plantarum L60 by individual factor experiments. The results indicated that nitrogen sources and inorganic salts significantly affected L. plantarum L60’s antioxidant and acid-producing abilities, and when the supplemental levels of peptone, casein hydrolysate, KH2PO4, MgSO4 and NaCl were 0.7%, 0.3%, 0.3%, 0.15% and 0.9%, respectively, the scavenging ability of antioxidant peptides on DPPH radical and superoxide anion reached the maximum.