Abstract:The effect of low temperature on the quality of fermented mustard roots was tested using various indicators，including brittleness，color，nitrite residual content，moisture content，water activity，amino acid nitrogen content，total acid content and reducing sugar content.Measurements were collected from mustard roots fermented at-1℃-5℃and 6℃-8℃，respectively.The results suggested that the brittleness and nitrite residual content of-1℃-5℃fermented mustard roots were significantly higher than those from 6℃-8℃fermented mustard roots（P<0.01）.However，both nitrite residual content from the two fermented mustard roots were lower than 0.6 mg/kg.The red value，yellow value（internal），total acid and reducing sugar content of 6 ℃-8 ℃ fermented mustard roots were significantly higher than those of-1 ℃-5 ℃ fermented mustard roots（P<0.01）.The water activity and amino acid nitrogen of 6℃-8℃fermented mustard roots were dramatically higher than those from-1℃-5℃fermented mustard roots（P<0.05）.There was no significant difference in the bright value between the two mustard roots fermented at different low temperatures（P>0.05）.