Development of steamed cake using red wine dreg as a natural colourant

Red yeast rice is a fermented rice that acquires its red colour from being cultivated with the yeast Monascus purpureus. It is widely used to produce various fermented foods in China, Japan, and East Asia. Red yeast rice has been reported to lower cholesterol, improve digestion, and possess antioxidant activity. Red yeast rice is a main ingredient in Foochow red wine. This study aimed to develop steamed cake by using Foochow red wine dreg as a natural food colourant. The steamed cake was prepared by mixing self-rising flour, sugar, raisins, water, and red wine dreg extract, and then steamed at high heat for 20 mins. The sensory qualities of the steamed cake were evaluated by fifty untrained panellists using a 7-point hedonic scale. The physicochemical properties and antioxidant activity of the product were determined. The overall acceptability score for the steamed cake was 5.80 out of 7 with an acceptance index of 83%. The mean scores for various sensory attributes were: colour (5.56), aroma (5.52), taste (5.72), and texture (5.26). The colour profile of the steamed cake was L* = 64.10±0.34, a* = 11.46±0.37 and b* = 21.94±0.68. The radical scavenging capacity DPPH was 53.47% with a total phenolic content of 2.35 mg GAE/g, and a total flavonoid content of 1.70 mg CE/g. The steamed cake contained 12.55% sugar and alcohol was not detectable. Red wine dreg provides an attractive colour to the cake. In summary, a healthier steamed cake with natural colourant and enhanced antioxidant activity was developed.