Extraction optimization and functional properties of corn germ meal albumin protein as a potential source of novel food ingredients

Abstract

Albumin is the main component of the protein of corn germ meal (CGM). In this study, we first optimized the CGM albumin extraction condition at a 1:11 mass ratio of CGM to water, 2.5 hr extraction time, and 35°C extraction temperature, from which 38.05% of the extraction rate was achieved. FTIR analysis showed that the extracted CGM albumin contained typical amide A, B, I, II, and III protein bands. Functional properties showed that the CGM albumin exhibited a relatively high water-holding capacity of 2.0 ml/g and a low oil-holding capacity of 0.6 ml/g. The CGM albumin has higher lysine content (5.6) than whole maize grain (2.73), and its nutritional composition is more in line with FAO/WHO standards. The DPPH and hydroxyl radical scavenging activity of the CGM albumin at 2 mg/ml were 91% and 92%, respectively. Our study demonstrated that CGM albumin has potential use as a food ingredient. Practical application Corn germ meal (CGM) is the by-product of the oil industry. It is rich in protein and has often been considered as a disposal waste in food processing. Albumin is the main component of the protein of CGM, and its extraction condition was first optimized in this study. The CGM albumin showed low oil-holding capacity, high antioxidant activity, and good water-holding capacity, emulsifying capacity, foaming capacity, and stability. We believe the results of this study will be a good guide for using CGM albumin as a food ingredient.