摘要 后发酵是曲霉型豆豉形成独特颜色、风味及营养物质的重要阶段,其中,氨基酸态氮(amino nitrogen,AN)是衡量豆豉后发酵程度的重要指标。为探索后发酵温度对曲霉型豆豉AN的生成动力学及品质的影响,以4种不同品种大豆(3种黄豆和1种黑豆)为研究对象,使用修正后的Gompertz方程拟合后发酵过程中的AN含量变化,测定不同温度下后发酵过程中的水分含量、pH值、褐变指数(browning index,BI)、总酸(total acid,TA)、AN及游离氨基酸(free amino acids,FAA)含量,并对这些指标进行相关性分析。结果表明:在45~65℃的后发酵温度内,修正后的Gompertz方程可以很好地拟合4种曲霉型豆豉的AN生成动力学(R 2>0.94),并且温度越高,AN的最大值和生成速率越低,但不同大豆品种的豆豉间AN最大值和生成速率无明显差异。相关性分析结果显示,4种豆豉呈现一致的趋势:温度与BI呈正相关(P<0.01),与TA、AN呈负相关(P<0.01)。另外,4种豆豉中的FAA含量随着温度的升高而降低。该文可为曲霉型豆豉的后发酵工艺研究提供理论支持。 Post-fermentation is a key stage for the special color,flavor and nutrients formation in Aspergillus-type Douchi,the extent of which is usually determined by an important indicator-amino nitrogen(AN).To investigate the influences of post-fermentation temperature on the AN formation kinetics as well as the quality of Aspergillus-type Douchi,the AN content change of four soybeans(three yellow soybeans and one black soybean)were measured at different post-fermentation temperatures,and fitted by the modified-Gompertz equation in this study.Moisture content,pH value,browning index(BI),total acid(TA),AN and free amino acids(FAA)contents were measured,and the correlation of these indicators was analyzed.The results showed that the modified-Gompertz equation could well describe the kinetics of AN production(R 2>0.94)for the four different Aspergillus-type Douchi at the post-fermentation temperature ranging from 45℃to 65℃.Though the maximum content values and production rates of AN were getting lower as the temperature increased,there was no significant difference in these indexes among the four Douchi.According to the correlation analysis,four Douchi have implied a consistent trend:temperature was positively correlated with BI(P<0.01),while negatively correlated with TA and AN(P<0.01).Moreover,the FAA content of the four kinds of Douchi decreased with the increase of temperature.Our work may provide theoretical support for the post-fermentation process of Aspergillus-type Douchi.
出处 《食品与发酵工业》 CAS CSCD 北大核心 2021年第9期91-99,共9页 Food and Fermentation Industries
基金 中央引导地方科技发展专项资金地方专业性技术创新平台类项目(CSTC2018ZYCXPT0006)。
关键词 曲霉型豆豉 后发酵 温度 氨基酸态氮 游离氨基酸 大豆品种 Aspergillus-type Douchi post-fermentation temperature amino nitrogen free amino acid soybean varieties
