Effect And Mechanism Of β-Glucan On Soybean Protein In Low/High Moisture Tissue

The further development of vegetable protein meat is limited by the poor taste,the single nutrient type and the addition of unnatural additives.Therefore,this paper attempts to prepare vegetable protein meat by combining β-glucan with soy protein isolate,in order to enrich vegetable protein nutrients and improve the quality of vegetable protein meat.The effects of β-glucan supplementation on physicochemical properties of low water/high moisture vegetable protein and its mechanism were investigated.The results are as follows:(1)The hardness of low-moisture vegetable protein meat decreases and then increases with increasing β-glucan addition,which is mainly influenced by the enhanced H-S-Q(hydrogen bonding,hydrophobic interactions,disulphide bonding interactions).The addition of 5% β-glucan promotes the formation of disulphide(S)and hydrogen(H)bonds,improving the oil-holding and cooking characteristics ofβ-glucan-soy protein isolate extrudates.It also promotes the formation of H and H-S-Q(interaction of hydrogen bonds,hydrophobic interactions,disulphide bonds)and disrupts Q-S(interaction of hydrophobic interactions and disulphide bonds)interactions to improve nutrient retention during subsequent processing.In addition,during low moisture extrusion β-glucan forms a larger molecular weight compound with the soybean isolate and the main forces maintaining this compound are S and H.(2)The water-holding capacity,water-solubility index and tensile strength of high-moisture vegetable protein meat decreased and chewiness increased with increasing β-glucan addition,which was mainly influenced by the reduced content ofβ-folded structures.5% addition of β-glucan deepened the colour of β-glucan-soy isolate extrudates by increasing the content of α-helix structures in the secondary structure and decreasing the content of β-folded and β-turned angles in the secondary structure,as well as improving the colour of β-glucan-soy isolate extrudates.In addition,the compounds formed by β-glucan and soy protein isolate under high moisture conditions were mainly maintained by the α-helix,β-fold and β-angle in the secondary structure.(3)The addition of β-glucan modulates the firmness of low/high moisture vegetable protein meat,thus improving the texture of the finished low/high moisture vegetable protein meat.At the same time,the addition of β-glucan helps to improve the oil-holding properties of the high-moisture/low-moisture vegetable protein meat,improving the juiciness of the product.In addition,the structure of the compounds formed by β-glucan and soy protein under low moisture extrusion is mainly maintained by S and H,while the structure of the compounds formed by β-glucan and soy protein under high moisture extrusion is mainly maintained by the α-helix,β-folding and β-turning in the secondary structure.