3 and processed at a pressure of 0 3 mpa for 0 5 min to generate a steam exploded wet straw material the steam exploded wet straw material was then added to and soaked in water in the weight equal to 4 times of that of the original straw material at 70 u00b0 c for 30 mins subsequently the steam exploded wet straw material was extruded using an extruder to separate and obtain a steam exploded straw hydrolyzate liquid and a steam exploded straw solid material the contents of cellulose hemicellulose and lignin in the steam exploded straw solid material were measured compared with the chemical composition of the original straw the degradation rate of the hemicellulose in the steam exploded and acid treated straw reached 60 see table 2 this example was carried out in a substantially same manner as in example 4 except that the straw was soaked in 0 04 wt of sulfuric acid for 30 mins the mass ratio of straw to acid was 1 2 the condition for the steam explosion included obtaining of a steam exploded wet straw material under a 0 6 mpa pressure for 2 minutes the conditions for the product collection included soaking the steam exploded wet straw material in water in the weight equal to 7 times of that of the original straw material at 70 u00b0 c for 45 mins the steam exploded wet straw material was extruded using an extruder to separate and obtain a steam exploded straw hydrolyzate liquid and a steam exploded straw solid material the contents of cellulose hemicellulose and lignin in the steam exploded straw solid material were measured compared with the chemical composition of the.