Application of antioxidant peptides derived from goat milk in ginger coffee formulation

Abstract

Peptides can be obtained from the degradation of goat milk protein by enzymatic hydrolysis method using food-grade papain enzyme. These peptides have antioxidant activity that can be applied to beverage formulations. This study aimed to characterize antioxidative peptides from whey and goat milk and to develop a ginger coffee drink formulation with antioxidant peptides. Protein hydrolysis was performed for 0, 15, and 30 mins and the highest degree of hydrolysis was obtained from protein samples which were hydrolyzed for 15 mins. The whey hydrolysate 15 mins had a protein concentration of 0.54±0.07 mg/mL and one protein band of 17 kDa. Goat milk peptides had a protein concentration of 1.71±0.00 mg/mL and one protein band of 15 kDa. This sample also has the highest antioxidant activity, where Whey peptides had an antioxidant activity of 79.98±0.86% while goat's milk peptides 94.97±0.44%. These two peptides were applied to ginger coffee drink formulation. The formulations with the highest antioxidant activity were ginger coffee with goat milk and whey peptides in a ratio of 4:1 (90.15±1.02%) and ginger coffee with goat milk (85.23±1.15%). Based on results from the organoleptic test, these two formulations were also acceptable to panellists in terms of taste, overall properties, and interest.