Abstract: [Objective] Using reconstituted milk as raw material,licorice extract,Lactobacillus helveticus,Streptococcus thermophilus and Lactobacillus bulgaricus were fermented to prepare flavored fermented milk.[Method]Through a single factor test,the effects of the addition amount of licorice liquid,sugar addition amount and fermentation time on the sensory quality of the test products were studied.Orthogonal experiment was used to design the optimal process parameters of licorice-flavored fermented milk.[Result]The best fermentation conditions were 3% of the fermenting agent,20% of the licorice liquid,6% of the sugar,the fermentation temperature of 42 ℃ and the fermentation time of 6 hours.The fermented milk has a delicious taste,sweet and sour taste,no obvious smell of Chinese medicine and bad smell.The fermented milk prepared according to the optimized process parameters has good storage stability and can keep the number of viable bacteria above 6.5 × 10⁸ CFU/ mL .[Conclusion]In this paper,a new taste of fermented milk is developed through experiments to broaden the market of fermented milk and meet the needs of consumers.

Key words: licorice, fermented milk, process conditions