传统发酵豆酱的养分变化分析

研究传统发酵豆酱发酵过程中的养分变化规律,从而为传统发酵豆酱的工业化生产控制奠定理论基础。以北方传统自然发酵豆酱为研究对象,应用国标法,测定了发酵不同阶段的水分、pH值、总酸、还原糖、氨基酸态氮、脂肪的变化。结果表明:在自然发酵过程中,14%含盐量的豆酱和8%含盐量的豆酱的养分变化情况大致一样,水分变化在64%和72%上下波动;pH值变化都是下降的;总酸含量变化都是上升的,发酵后期趋于平缓;氨基酸态氮含量变化都是逐渐增加,但最后又略有下降;还原糖含量变化都是前2周下降,2～4周急剧上升,4～5周急剧下降,5～7周略有下降;脂肪含量变化都是下降的,但前2周缓慢下降,2～7周急剧下降后趋于平缓。14%含盐量的豆酱与8%含盐量的豆酱相比水分含量低、pH高、总酸含量低、氨基酸态氮含量低、脂肪含量高。

Analysis of nutrient change for the traditional fermented soybean paste

This research focused on observation of nutrient dynamics of the traditional fermented soybean paste during fermentation process,which was the theoretical foundation for the control of industrialized production of traditional fermented soybean paste.The change of moisture,pH,total acids,reducing sugars,amino acid nitrogen and fat were measured with national standard method during the different stages of fermentation process of the northern traditional natural fermented soybean paste.Results showed that soybean paste with 14% salt was roughly the same as soybean paste with 8% salt in nutrient changes during the natural fermentation process,and their moisture fluctuated between 64% and 72%.Additionally,although their pH was declined,the contents of total acids increased at first and then flattened in later stage of fermentation.The contents of amino acid nitrogen were gradually increased at first,but finally slightly decreased.The contents of reducing sugars were declined in the first two weeks and then sharply raised from the week 2 to 4,then sharply declined from week 4 to 5,then slightly declined from week 5 to 7.Furthermore,the contents of fat were slowly declined in the first two weeks,and then leveled off after sharply declined from week 2 to 7.The contents of moisture,total acids and amino acid nitrogen of soybean paste with 14% salt were lower than those of soybean paste with 8% salt during the whole fermentation process,but the pH and the content of fat were opposite.