黑木耳粉对黑米凝胶物化特性及结构的影响

Effect of Auricularia auricular-judae Powder on the Physicochemical Properties and Structure of Black Rice Gel

为了改善黑米的加工性能,以黑米粉为原料,通过添加不同量的黑木耳粉(5.0%、10.0%、15.0%、20%),考察其对黑米粉糊化特性、热力学特性及其形成黑米凝胶的流变特性、质构特性以及微观结构的影响。添加黑木耳粉可以显著提高黑米的粘度并促进冷却过程中的凝胶化,其中添加量为20%的黑木耳粉效果最好。添加黑木耳粉会抑制黑米凝胶内水分的流动,使硬度及弹性显著增大,糊化焓从3.01 J/g增加到5.94 J/g,羟基伸缩振动峰从3390 cm^(–1)降低到3374 cm^(–1),黑木耳粉可以提高黑米凝胶结构的稳定性。扫描电镜结果显示,添加黑木耳粉的黑米凝胶孔洞明显小于纯黑米凝胶,且孔洞周围的基质层较厚,进一步解释了黑木耳粉对改善黑米凝胶结构效果的机制。综上可见,添加黑木耳粉对黑米凝胶物化特性和结构影响显著。

In order to improve the processing performance of black rice,black rice flour was used as raw material and different amounts of black fungus powder(5.0%,10.0%,15.0%,20%) were added to investigate its effect on the gelatinization and thermodynamic properties of black rice flour.The influence of rheological properties,textural properties and microstructure on its corresponding black rice gel was also studied.Adding Auricularia auricular-judae powder can significantly improve the viscosity of black rice and promote the gelation of black rice during cooling,among which adding 20% Auricularia auricular-judae powder had the best effect.The addition of Auricularia auricular-judae powder can inhibit the flow of water in black rice gel,and increase the hardness and elasticity of black rice gel significantly.The gelatinization enthalpy of black rice gel increased from 3.01 J/g to 5.94 J/g,and the hydroxyl stretching vibration peak of black rice gel decreased from 3 390 cm^(–1) to 3 374 cm^(–1).The stability of black rice gel structure was improved by adding Auricularia auricular-judae powder.The SEM results showed that the pores of black rice gel supplemented with Auricularia auricular-judae powder were significantly smaller than that of pure black rice gel,and the matrix layer around the pores was thicker,which further explained the mechanism of Auricularia auricular-judae powder on improving the structure of black rice gel.In conclusion,the effect of Auricularia auricular-judae powder on the physicochemical properties and structure of black rice gel was significant.