Microbiological, chemical, fatty acid and antioxidant characteristics of goat milk kefir enriched with Moringa oleifera leaf powder during storage

Abstract

Fortification of compounds that contain functional components can improve product quality without affecting the product characteristics in the storage. This study evaluated the effect of supplementing Moringa leaf powder (0; 0.5; 1.0; 1.5; 2.0% w/w) and different storage periods (0, 7, and 14 days) on the quality of goat milk kefir. The observed parameters were microbiological characteristics (total lactic acid bacteria (LAB), total plate count or TPC, total yeast) chemical characteristics (total solids, acidity, pH, alcohol level, free fatty acid (FFA)), fatty acid profiles, and antioxidant properties (total phenol and DPPH). The result showed that Moringa leaf powder supplemented into kefir increased acidity, total phenol, and DPPH and decreased the alcohol level. Storage time decreased TPC, total yeast, and total solids but increased alcohol, total phenol, and DPPH. We also identified 31 fatty acids. Supplementing 2% Moringa leaf powder combined with 14-day storage can produce ± twice as much total phenol and DPPH as those in the control group and does not negatively affect the quality of the kefir product.