Fermented milk is a product that was produced from fermentation of fresh milk using lactic acid bacteria, such as Lactobacillus bulgaricus and Streptococcus thermophilus. A variety of plant materials can also be used as raw material in making of fermentation drinks, such as nuts and tubers. The purpose of this study was to investigate the characteristics of fermentation drink made from juice of winged bean sprout and red sweet potatoes. The treatment in this study is the level of mixing between juice of winged bean sprout with red sweet potatoes , consist of ;A (30:70), B (40:60), C (50:50), D (60:40) and E (70:30). Completely randomized design had been used with 5 treatments and 3 replications. The data colected was pH, viscosity, protein content, fat content, total solids, total acid, ash content, calcium content, total lactic acid bacteria, total plate count and sensory evaluation. Data processing is performed using statistical 8, followed by Tuckey test HSD All-Pair wise Comparisons Test at level of 5%. Mixing of winged bean sprouts with red sweet potato can increase the value of pH, viscosity, protein content, fat content, total solids, total acid, ash content, calcium content, and total lactic acid bacteria. The best product was the product of B (40% winged bean sprout and 60% red sweet potatoes) already meets SNI 7552:2009, contain : 2.36% protein content, fat content of 1.24%, 18.77% total solids, pH was 4, 2, 0.54% total acid, 0.23% ash content, 0.173% calcium content, viscosity was 3.56 DPA, total lactic acid bacteria (CFU / ml) was 1.9 x10 10 , total plate count was 2.1 x10 10 (CFU / ml).
