The effect of high fructose syrup concentration on physicochemical, microbiological, and sensory properties of goat milk kefir with butterfly pea extract

Abstract

Goat milk kefir is valued for its probiotic and nutritional benefits but exhibits suboptimal sensory qualities when combined with butterfly pea extract. The addition of HFS as a sugar source can ensure optimal fermentation and improve the sensory quality of kefir. This study aimed to determine the effect of HFS on the characteristics of goat milk kefir with butterfly pea flower extract in terms of physicochemical, microbiological, and sesnory properties. A Completely Randomized Design (CRD) with five HFS concentrations (0%, 2.5%, 5%, 7.5%, and 10%) and four replications was used. Parameters measured included total acidity, pH, total yeast, total lactic acid bacteria (LAB), total soluble solids (TSS), antioxidant activity, and sensory attributes (color, aroma, taste, texture, soda sensation, and overall acceptance). Results showed that HFS addition significantly increased total acidity, TSS, and LAB counts, while pH and total yeast counts were unaffected. Total acidity ranged from 1.45±0.11 to 1.96±0.11%; pH from 3.86±0.099 to 3.95±0.11; TSS from 8.18±0.15 to 13.78±0.21 °Brix; antioxidant activity decreased from 68.83% to 42.64%; LAB counts increased from 8.38±0.10 to 9.15±0.01 log CFU/mL; and total yeast ranged from 5.89±0.22 to 6.49±0.17 log CFU/mL. The optimal HFS concentration was 7.5%–10%, producing kefir with enhanced functional, physicochemical, and sensory qualities and highest panelist acceptance.