Experimental research on storage of condensed stalk juice and composition analysis of juice of sweet soghum stalk

Nutrient contents of stalk and its juice of three varieties of sweet sorghum including Liaotian No.1, Zaoshu No.1 and Chuntian No.2 were analyzed and experimental research on storage of condensed stalk juice was carried out in order to increase utilization rate and extend storage time of sweet sorghum for fuel ethanol production. Results showed that all the three sweet sorghum varieties contained plentiful sugar, which can provide enough carbon source for alcohol fermentation, however, total nitrogen and some mineral elements（Fe^3＋）cannot meet the needs of alcohol fermentation. Activity of most microbes in stalk juice can be inhibited and the sugar can be maintained when the stalk juice was condensed to 4～5 times. Due to the reasons that the activity of acetous microbe or hydrolysis enzyme inside stalk juice can be maintained, ratio of reducing sugar to total sugar was increased with storage time at 55～60℃，0.15 MPa vacuum condensed condition, which can be beneficial for the purpose of alcohol fermentation.