Production of a Functional Yogurt Drink Enriched with Black Rice Beverage

There are a many previous studies focusing on the production of probiotic yoghurt based on raw materials like oat and soy milk; however, little is known about the usage of black rice beverage in fermented dairy products. In the present study, four different types of yoghurt drinks were produced, where cow's milk yogurt was replaced with 10, 20, 30, and 40% of black rice beverage in the yogurt drink formula and stored for 15 days at 4°C. Physical, chemical, phytochemical, microbiological, and sensory characteristics of the drink samples were performed at the zero, 5, 10 and 15 days of the storage. We found that the addition of black rice beverage to yoghurt drink formula significantly increased total solids, protein, anthocyanin, phenolics, antioxidant activity, pH, and viscosity values but decreased the values of acidity, fat, ash, and acetaldehyde of yoghurt drinks. The addition of black rice beverage increased the total bacterial and bifidobacteria counts. In the sensory analysis, scores decreased as the black rice beverage proportions in yoghurt drink formula was increased. Based on the panelists' report, T1 and T2 samples (Replaced cow's milk yogurt with 10 and 20% of the black rice beverage in the yogurt drink formula, respectively) were the closest samples to the control sample (Yogurt drink made from 100% cow's milk). The consumption of such products is continuously increasing as the customers' tendency to consider them as functional products rather than traditional food products increase.