Abstract: In an effort to understand the effect of co-fermentation with Saccharomyces cerevisiae and Pediococcus pentosaceus at different ratios on the quality characteristics of Pucheng Chuantou steamed bread and hence obtain the optimal ratio, 5 steamed bread samples were made with combined starter cultures of Saccharomyces cerevisiae and Pediococcus pentosaceus at ratios of 10:1, 1.5:1, 1:1, 1:1.5, and 1:10, and their pH, texture and aroma were evaluated and compared with those of the sample made by the successor of intangible cultural heritage. The results showed that pH increased firstly and then decreased with increasing proportion of Pediococcus pentosaceus, reaching a minimum at a ratio of 1:1. The texture was evaluated by principal component analysis, and the overall sensory scores were established. It was found that better texture characteristics were obtained at ratios of Saccharomyces cerevisiae and Pediococcus pentosaceus of 1:10 and 1:1. The five steamed bread samples were diverse in flavor, and the highest number (15) of volatile aroma substances was detected from each of the steamed bread samples made with 1:1 and 1:10 mixtures of Saccharomyces cerevisiae and Pediococcus pentosaceus, with the former containing higher contents of ketones, alcohols, esters and acids. Overall, Chuantou steamed bread made with 1:1 mixture of Saccharomyces cerevisiae and Pediococcus pentosaceus was the best in terms of sensory evaluation, pH, texture and flavor.

Key words: Chuantou steamed bread, pH, textural properties, flavor, sensory quality