Abstract: In order to study the preservation of sugarcane juice,lemon juice and glucose oxidase were added into fresh sugarcane juice.By single factor experiments,the amount of glucose oxidase (A),enzymolysis temperature (B),enzymolysis time (C) and lemon juice volume (D),on preservative effect of sugarcane juice,were investigated.On the basis of single factor experiments,the L₉(3⁴) orthogonal tests were designed.The optimal combination were confirmed and the sample was characterized by UV and FT-IR.The result showed that at 20 ℃,the optimal conditions for preservation were:sugarcane juice of 40 mL,the amount of glucose oxidase of 0.060 mg,enzymolysis temperature of 30 ℃,enzymolysis time of 10 min and lemon juice volume of 1 mL.The relationship between primary and secondary factors were lemon juice volume,enzymolysis temperature,amount of glucose oxidase and enzymolysis time.Under the optimal conditions,sugarcane juice can effectively keep preservation for 12 days.The UV spectra of the samples of 12 days and fresh sugarcane juice was basically the same,and the IR spectra all had the absorption peak of quinones.Ultraviolet color group C=C,C≡C and conjugated polyene of the samples after modification was destroyed and had no infrared quinone absorption peaks.

Key words: sugarcane juice, preservation, glucose oxidase, lemon juice