PEMANFAATAN UBI JALAR UNGU (Ipomoea batatas L.) SEBAGAI YOGURT DENGAN OPTIMALISASI KARAKTERISTIK FISIK DAN KIMIA

Background: Recently, there were many kind of food which had benefits for our health, including functional food. Purple sweet potato was one of local food which had high potency as functional food. Not only nutritious, but also it has a lot of active components such as phenolic acid, anthocyanin, and tocopherol which were antioxidants that could prevent the occurrence of many diseases. Purple sweet potato as functional food can be consumed in the form of yogurt. Meanwhile in the making of yogurt, there were little concern regarding variation and processing method of the raw materials. Previous studies showed that processing method could affect the antioxidant level. Hence that would be necessary to compare the physical and chemical characteristics between different treatment of raw materials, in the form of powder and paste. Objective: To determine the physical characteristics (viscosity) and chemical (pH, total of titrated acid, anthocyanins, antioxidant activity) purple sweet potato yogurt made from powder and purple sweet potato paste. Methods: It was experimental research with a completely randomized design. Yogurt is made from purple sweet potato powder and purple sweet potato paste. The physical properties were viscosity. Chemical properties were pH, total of titrated acid, anthocyanins, and antioxidant activity. Statistical analysis Independent Samples T-test to test the viscosity, whereas pH and total titrated acid were tested with Mann-Whitney test, and anthocyanin level and antioxidant activity were tested with One Way Anova. Results: Differences in the processing of the raw materials of yogurt in the form of powder and paste caused significant differences in the viscosity of yogurt (p<0.05). There were significant differences in pH, total titrated acid, anthocyanin level, and antioxidant activity between yogurt from purple sweet potato paste and yogurt from purple sweet potato powder (p