Study On The Preparation Process Of Glucose By Hydrolyzing Cellulose And Dietary Safety Evaluation Of This Sugar Solution

This paper describes the experiments of optimizing the processing procedure of hydrolyzing cellulose into glucose with dilute acid,the detoxification of the sugar solution and the evaluation of its dietary safety.The experimental results are summarized as follows:1 The optimization of the procedure of hydrolyzing cellulose with dilute acid. The experiment established the best reaction conditions(including acid concentration, reaction time and temperature) of hydrolyzing quantitative filter papers with hydrochloric acid,sulphuric acid,oxalic acid and acetic acid by orthogonal experiments,respectively.By hydrochloric acid,the ability sequence of influencing the efficiency of hydrolyzing cellulose was A>B>C and the best combination of experimental conditions is A3B3C1,i.e.an acid concentration of 20%,a reaction temperature of 100℃and a reaction time of 1h with a conversion of 42.1%cellulose into glucose.By sulphuric acid,the ability sequence of influencing the efficiency of hydrolyzing cellulose was B>A>C and the best combination of experimental conditions is A3B3C1,i.e.an acid concentration of 40%,a reaction temperature of 100℃and a reaction time of 1h,with a conversion of 38.2%cellulose into glucose.By oxalic acid,the ability sequence of influencing the efficiency of hydrolyzing cellulose was A>B>C and the best combination of experimental conditions is A3B1C2,i.e.an acid concentration of 30%,a reaction temperature of 40℃and a reaction time of 1.5h, with a conversion of 41.6%cellulose into glucose.By acetic acid,the ability sequence of influencing the efficiency of hydrolyzing cellulose was A>C>B and the best combination of experimental conditions is A2B2C1,i.e.an acid concentration of 10%, a reaction temperature of 70℃and a reaction time of 1h,with a conversion of 40.2% cellulose into glucose.2 The removing impunity of the sugar solution made from hydrolyzing cellulose.Through the comparison of different removing impunity methods,the process procedures of over-neutralizing acidic hydrolysates of cellulose with Ca(OH)₂ combined with the absorption by activated carbon and then concentration by evaporation was chosen to removing impunity of the sugar solution made from hydrolyzing cellulose in further experiments.3 Animal feeding tests for evaluating the dietary safety of detoxified sugar solution made from hydrolyzing cellulose.(1)The result of acute toxic tests indicated that LD₅₀ of the two substances tested on male and female rats is higher than 20g/(kg.bw),respectively.And so,according to the National Food Safety Toxicity Evaluation Criteria,it was suggested that the cellulosic hydrolysate should be innocuous.(2) In 30-day feeding test,all of the rats still grew well.The blood hemoglobin contents,RBC and WBC of all rats in different groups tested are all normal.There was no significant difference(P>0.05) between the blood hemoglobin contents and RBC of the rats in the two testing groups and those in the control group, while there was a significant difference(P<0.05) between WBC of the rats in the two testing groups and that in the control group.The results of their gross anatomy and observation on their behaviors indicated no abnormalities in comparison with the control group.