Heo Sojeong, Park Junghyun, Lee Kwang-Geun, Lee Jong-Hoon, Jeong Do-Won
Department of Food and Nutrition, Dongduk Women's University, Seoul, 02748, Republic of Korea.
Department of Food Science and Biotechnology, Dongguk University-Seoul, Goyang, 10326, Republic of Korea.
Heliyon. 2023 Feb 27;9(3):e14092. doi: 10.1016/j.heliyon.2023.e14092. eCollection 2023 Mar.
Three candidate starter strains- SNU-G, sp. KACC 46077, and KACC 40256-were inoculated into soybean, as individual strains or in combination, to assess their roles in fermentation. All the strains increased the pH, amino-type nitrogen, and moisture content of the soybean during fermentation, and decreased the lightness, redness, and yellowness. The inoculated strains increased to an average density of 1.37 × 10 spores/g (from the initial 5.0 × 10 spores/g) after 20 days of fermentation. Forty-two volatile compounds, including an acid, alcohols, carbonyls, furans, and a pyrazine, were more abundant in soybean fermented with starters than in controls. SNU-G increased the pH more than the other strains and produced more volatile alcohol compounds. KACC 40256 resulted in the lowest reduction of redness and yellowness during the fermentation and produced large amounts of carbonyl compounds, including two specific volatile compounds, 2-hydroxy-3-methylcyclopent-2-en-1-one and (3)-3-ethyl-2-methylhexa-1,3-diene. sp. KACC 46077 contributed the least to pH change and volatile compound production, and did not produce specific volatile compounds. Although no significant synergy in the production of volatile compounds was found when using mixtures of strains compared with application of single strains, the quality of fermented soybeans was confirmed to be different depending on the strain(s) applied.
将三株候选起始菌株——SNU - G、KACC 46077菌株和KACC 40256菌株分别单独或混合接种到大豆中，以评估它们在发酵过程中的作用。在发酵过程中，所有菌株均提高了大豆的pH值、氨基态氮含量和水分含量，并降低了大豆的亮度、红度和黄度。发酵20天后，接种的菌株平均密度增加到1.37×10孢子/克（初始为5.0×10孢子/克）。与对照相比，用起始菌株发酵的大豆中含有42种挥发性化合物，包括一种酸、醇类、羰基化合物、呋喃类和一种吡嗪类，含量更为丰富。SNU - G比其他菌株更能提高pH值，并产生更多的挥发性醇类化合物。KACC 40256在发酵过程中导致红度和黄度降低最少，并产生大量的羰基化合物，包括两种特定的挥发性化合物，2 - 羟基 - 3 - 甲基环戊 - 2 - 烯 - 1 - 酮和（3）- 3 - 乙基 - 2 - 甲基己 - 1,3 - 二烯。KACC 46077菌株对pH值变化和挥发性化合物产生的贡献最小，且不产生特定的挥发性化合物。尽管与单一菌株应用相比，使用混合菌株时未发现挥发性化合物产生有显著协同作用，但发酵大豆的品质因所应用的菌株不同而得到证实有所差异。
