Abstract: [Objective] With fresh lotus root,mixed recovery milk and white sugar as raw materials,the coagulated yogurt with unique flavor was prepared by composite fermentation. [Method] The production process of lotus root yogurt was optimized based on response surface method with the addition amount of lotus root juice,white sugar,fermentation time and starter inoculated amount as single-factor variables. The preparation technology of lotus root yogurt was optimized based on the sensory score and acidity. [Result] The optimal parameters were determined by sensory score and acidity determination:：lotus root juice added 11.99%,whole milk powder added 12.50%,white sugar added 6.28%,starter inoculated 0.12%,and fermented at 42 ℃ for 6.24 h.The sensory score of lotus root yogurt was 89.80 points,and the acidity was（98.61±0.95）°T. [Conclusion] Lotus root yogurt has uniform color,less whey precipitation,soft taste,sweet and sour taste,with unique fragrance of lotus root and yogurt.

Key words: lotus root, coagulated yogurt, response surface method, production technology