Changes of methanol content during pectinase clarification of honey melon juice

Objective: The relationship between the clarification effect and methanol content of honeydew-melon juice was investigated during the optimization of pectinase treatment process. Methods: The effects of pectinase addition, pH value, reaction time, and processing temperature on the clarity and methanol content of honeydew-melon juice were investigated through single factor and orthogonal experiments, by using the transmittance and methanol content as indicators. Results: The order of influencing factors on clarity and methanol content of juice was pH value ＞ pectinase addition ＞ action time ＞ temperature. The optimal conditions for producing honeydew-melon juice with high clarity and high methanol concentration were 0.04 g/100 mL of pectinase addition, pH value of honey melon juice 4.0, action time 120 min, and treatment temperature 35 ℃. Under the control of these conditions, the amount of methanol produced was 423.79 mg/L, and the light transmittance of honeydew-melon juice was 95.71%. Conclusion: The methanol content is positively correlated with the clarity of honeydew-melon juice. More completed pectin decomposition and higher methanol content can result in higher light transmittance of honeydew-melon juice.