The correlation between spore generation and temperature,and correlations between amino nitrogen content and browning degree,laccase activity were analyzed by determining laccase activity of bacteria strains isolated and preserved by microbiological laboratory of Guizhou university to explore methyl catechol browning oxidized by laccase and browning path of L-tyrosine oxidation under ABTS condition for study the effect of laccase in bacillus on browning of fermented soybean.The results showed that:1)Spore content and browning degree of the simulation fermented soybean increase with temperature increment during the browning process of the simulation fermented soybean fermented by bacillus strains;2)Laccase activity of bacillus strains is up to maximum at 60℃,which is consistent with accumulation temperature of high temperature Daqu with Maotai-flavor;3 )Pearson's correlation coefficients with significant correlation between browning of the fermented soybean and laccase activity,amino nitrogen content of fermentation products are 0.617 and 0.766;4)Brownness substance can be produced from methyl catechol oxidized by laccase of bacillus strains,and brownness substance can be produced by oxidizing L-tyrosine by laccase of bacillus strains under ABTS condition also.In conclusion,browning caused by laccase of bacillus strains has the certain effect on browning of Daqu with Maotai-flavor during the fermentation process.%为研究芽孢杆菌漆酶是否在酱香型高温大曲的褐变中起作用，通过对贵州大学微生物实验室分离及保存的芽孢杆菌进行芽孢杆菌漆酶活性测定，分析芽孢生成情况与温度的关系以及酱香模拟曲褐变程度、漆酶活性和模拟发酵物氨基态氮含量之间的相关性，探索漆酶氧化愈创木酚褐变以及小分子化合物介导的酪氨酸氧化褐变途径。结果表明：1）在芽孢杆菌发酵模拟曲褐变的过程中，随着温度升高，发酵物中芽孢含量随之增加，发酵曲褐变程度也随之加深；2）芽孢杆菌漆酶在60℃时活性最高，与酱香型高温大曲的堆积温度相吻合；3）漆酶活性、发酵产物氨基态氮含量与发酵物褐变之间的皮尔逊相关系数分别为0．617和0．766，均呈显著相关；4）在酱香曲中存在的愈创木酚能被芽孢杆菌漆酶氧化产生褐色物质，芽孢杆菌漆酶在小分子介体物质存在情况下能够氧化酪氨酸，产生褐色物质。结论：芽孢杆菌漆酶所引起的酶促褐变在酱香型大曲的褐变中起着一定的作用。
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