Extraction Of β-glucan From Hericium Erinaceus And Lentinus Edodes And Its Application In Bread

In this paper, the enzyme-assisted extraction of Hericium erinaceus β-glucan(HEBG) and Lentinus edodes β-glucan(LEBG), physicochemical properties and its application in bread were studied. The main experiment results were as follows:The optimal extraction conditions of HEBG were as follows:composite enzyme dose 1.5%, the ratio of enzyme complex (cellulase, pectinase, papain) 1:1:1; pH value 5, enzymolysis temperature 60 ℃, enzymolysis time 60 min, resulted in the highest HEBG yield, with a value8.68%. The optimal extraction conditions of HEBG were as follows: composite enzyme dose 2.0%, the ratio of enzyme complex (cellulase, pectinase, papain) 1:1:1; pH value 5, enzymolysis temperature 55 ℃, enzymolysis time 60 min, resulted in the highest HEBG yield, with a value 12.98%.The polysaccharide contents of HEBG and LEBG were determined by phenol-sulfuric acid method, the polysaccharide contents were 93.7% and 84.3% respectively. The molecular weight of HEBG and LEBG were characterized by HPLC. The results showed that HEBG and LEBG have high purity, the Mw and Mn of HEBG were 2.120×106,2.084× 106 Da respectively; the Mw and Mn of LEBG were 1.868×106,1.854×106 Da.Combined with ultraviolet and infrared analysis results, HEBG and LEBG doesn’t contain protein and nucleic acid, mainly includes beta glucan.The effects of HEBG and LEBG on the pasting properties and starch digestibility of bread wheat flour were investigated; the results showed that both HEBG and LEBG have an effect on starch gelatinization and inhibiting the digestion of starch, which is related to its solution viscosity. As concentration of HEBG and LEBG increased, the effects on inhibiting starch digestion were better.The influences of HEBG and LEBG on the qualities and in vitro starch digestion of bread were investigated. Results showed that specific volume of HEBG/LEBG bread increased slightly as compared to control samples. The results of sensory evaluation and TPA test showed the bread with 0.5 and 1.0% HEBG/LEBG, its structure inside looked exquisite, which also had better springiness and lower hardness. At the same time, adding HEBG/LEBG could make the bread stale much slower. The digestion in vitro model revealed the addition of HEBG/LEBG decreased the starch digestibility in bread, the rapidly digestible starch reduced, slowly digestible starch and resistant starch increased.