Abstract:To obtain the optimal conditions of ever-fresh lactone tofu and simplify the evaluation and prediction of fresh preservation effect,single-factor experiments and orthogonal design L9(34) were conducted involving sterilization temperature,sterilization time,consumption of coagulation.The results showed that:the preservation period could be improved significantly at the sterilization temperature of 87 ℃ with sterilization time of 30 min,with coagulant(GDL) concentration at 0.4% and preservative addition at 0.45 g/kg,natural pH and refrigerator temperature at 4 ℃.Preservation index was determined by the two main indicators through factor analyses followed by reducing dimensionality of original amount.The equations we found in the process are Z1=-0.962X1+ 0.883X2+0.785X3-0.302X4+4.594E-02X5,and Z2=0.246X1-0.395X2+0.545X3+0.934X4-0.932X5.It is not only just providing a feasible technical way to keep lactone tofu fresh,but also convenient for quality evaluation and prediction.