高压均质化改性竹笋膳食纤维对虾糜凝胶特性及化学作用力的影响

Effect of High-Pressure Homogenization Modified Bamboo Shoot Dietary Fiber on Gelation Properties and Chemical Interactions of Shrimp Surimi

为提高竹笋膳食纤维(bamboo shoot dietary fiber,BSDF)的利用率,采用高压均质法对其进行改性处理,探究不同高压均质条件(30、40、50 MPa和60 MPa)对BSDF水合性质和结晶度的影响以及添加高压均质化改性BSDF对虾糜热诱导凝胶强度、持水力、蛋白质二级结构、化学作用力及微观结构的影响。结果显示BSDF的持水力、持油力和膨胀力与压力总体呈显著正相关(P<0.05),但纤维颗粒粒径过小也会影响其与亲水基团等的结合,使吸水溶胀性降低;X射线衍射光谱和扫描电镜分析结果表明改性后的BSDF结晶度显著降低,纤维束状结构被破坏,呈现疏松多孔的结构。相比未改性BSDF,添加30、40、50 MPa和60 MPa高压均质处理BSDF的虾糜凝胶强度分别提高了10.04%、17.87%、28.76%和28.49%;持水力分别增加了3.48%、5.74%、13.04%和12.70%。傅里叶变换红外光谱分析结果表明,添加改性BSDF虾糜凝胶的α-螺旋和无规卷曲含量降低,而β-折叠和β-转角含量显著增加,虾糜凝胶蛋白质二级结构更加稳定。化学作用力分析结果表明,改性BSDF促进了虾糜凝胶的疏水相互作用和二硫键的形成,其中添加50 MPa和60 MPa BSDF虾糜组上述作用力强于其他组别。扫描电镜观察结果表明,60 MPa组虾糜凝胶具有更加均匀致密的三维网络结构。综上,高压均质处理可提高BSDF的水合性质并降低其结晶度,显著提高虾糜的凝胶特性;本研究可为促进BSDF在虾糜凝胶体系中的应用提供理论基础。

The effects of high-pressure homogenization(HPH)at different pressures(30,40,50 and 60 MPa)on the hydration properties and crystallinity of bamboo shoot dietary fiber(BSDF)were studied as well as the effect of HPH-treated BSDF on the gel strength,water-holding capacity(WHC),protein secondary structure,chemical interactions and microstructure of heat-induced gels from shrimp surimi.The results showed that the WHC,oil-holding capacity(OHC),and swelling capacity of BSDF were positively correlated with homogenization pressure(P<0.05).However,too small size of fiber particles affected its combination with hydrophilic groups,which could reduce the water absorption and swelling properties.X-ray diffraction(XRD)and scanning electron microscopic(SEM)results demonstrated that the crystallinity of BSDF decreased after medication,and the fiber bundle structure was destroyed,becoming loose and porous.Compared with the surimi added with unmodified BSDF,the gel strength of shrimp surimi added with BSDF treated at 30,40,50,and 60 MPa were increased by 10.04%,17.87%,28.76%,28.49%,and WHC increased by 3.48%,5.74%,13.04%,and 12.70%,respectively.Fourier transform infrared(FTIR)spectral analysis showed that the contents ofα-helix and random coil in the modified BSDF-supplemented shrimp surimi gel decreased,while the contents ofβ-sheet andβ-turn increased significantly,suggesting more stable secondary structure of proteins.The results of chemical interaction analysis showed that modified BSDF promoted the hydrophobic interactions and the formation of disulfide bonds in shrimp surimi gel,with a more pronounced effect being observed with BSDF treated at 50 and 60 MPa.SEM results showed that shrimp surimi gel added with BSDF treated at 60 MPa had a more uniform and denser three-dimensional network structure.These results showed that HPH treatment could improve the hydration properties,and reduce the crystallinity of BSDF,and HPH-treated BSDF could significantly enhance the gelation properties of heat-induced shrimp surimi,which will provide a theoretical basis for improving the application of BSDF in shrimp surimi gels.