Abstract:This study was undertaken to determine the effect of pectinase， substrate， and yeast strain on main alcoholic constituents， such as methanol， ethanol， propnol， isobutanol and isoamyl alcohol， of hard cider made from Crispin apples. The methanol concentrations of hard cider varied considerably and were dependent on the type of raw material used. Apple pomace yielded the greatest amount of methanol whereas apple juice produced lower methanol concentration than apple mash. The pectinase treatment significantly increased the methanol concentrations of all hard cider samples made from Crispin apples. However， pectinase and yeast strain had no influence on the concentrations of ethanol， n-propanol， iso-butanol and iso-amyl alcohol.