Physicochemical Properties of Fermented Milk Supplemented with Helianthus tuberosus Powder

Abstract

Helianthus tuberosus is a perennial plant in the genus, Asteraceae. Pork potato has various pharmacological functions such as improving constipation, preventing bowel disease, inhibiting colon cancer, reducing serum cholesterol, lowering blood lipids, and enhancing blood sugar. This study investigated the physicochemical properties of fermented milk by adding Helianthus tuberosus powder. During the fermentation process, the pH of the fermented milk with added Helianthus tuberosus was higher after 16 hours of fermentation. At 48 hours of fermentation, the pH decreased to 3.70, 3.65, 3.63, and 3.59 with 0% (the control group), 1%, 3%, and 5% Helianthus tuberosus added, respectively. In the last 48 hours of fermentation, the acidity increased to 2.35%, 2.57%, and 3.17% with 0% (the control group), 1%, 3%, and 5% Helianthus tuberosus added, respectively. The number of lactic acid bacteria increased as the quantity of Helianthus tuberosus added increased. The highest number of lactic acid bacteria was 9.96 log CFU/g after 16 hours of fermentation with a 5% addition of Helianthus tuberosus . After 48 hours of fermentation, the amount of lactic acid bacteria decreased to 7.84 log CFU/g and 7.88 log CFU/g in the control group and the 1% added Helianthus tuberosus group, respectively. The addition of 3% and 5% Helianthus tuberosus increased the lactic acid bacteria count to 9.48 log CFU/ g and 9.81 log CFU/g, respectively. As the fermentation time increased, oxalic acid and tartaric acid decreased but lactic acid increased. Lactose degraded galactose and glucose over time. After 48 hours of fermentation, the viscosity in the control, 1%, 3%, 5% added Helianthus tuberosus groups increased to 1,006 cP, 1,026 cP, 1,040 cP, and 1,106 cP, respectively. The antioxidant effect was higher in the 5% added Helianthus tuberosus group (84.14%) than in the control group (80.39%) at 48 hours of fermentation. The concentration of polyphenol was 1.6 mg/g and antimicrobial activity was strong against E. coli and Staphylococcus aureus.