酸性热致大豆分离蛋白聚集体制备高冻融稳定性类蛋黄酱乳液

Mayonnaise-like Emulsions with High Freeze-thaw Stability Prepared by Acid-heat-induced Soy Protein Isolate Aggregates

本文对酸性(pH 3.0)热致大豆分离蛋白聚集体(AHSPI)的平均粒径(Dh)、表面电位(ζ)、表面疏水性(H0)与溶解度进行了表征与测定,并用酸性(pH 3.0)天然大豆分离蛋白(ANSPI)、中性(pH 7.0)热致大豆分离蛋白聚集体(HSPI)作为对比分析,同时选用了AHSPI代替蛋黄制备高冻融稳定性的类蛋黄酱乳液,探讨了不同蛋白浓度对类蛋黄酱乳液的外观质地、微观结构、流变性质、DSC特性的影响。结果表明:AHSPI的平均粒径(204.67 nm)及H0(79418)均大于ANSPI与HSPI(pH 7.0),但ζ电位绝对值(35.93 mV)小于ANSPI与HSPI(pH 7.0),溶解度(89.47%)较HSPI(pH 7.0)更好。用AHSPI制备的类蛋黄酱乳液经过3次冻融循环保持稳定的最低浓度可达0.3 wt%,冻融前后乳液结构保持不变,只是乳液粒径的略微增大,流变性质表明类蛋黄酱乳液具有以弹性为主的凝胶网络结构,随着蛋白浓度的增大,油滴粒径逐渐减小,粘弹特性增强。DSC热分析表明:随着蛋白浓度的增加,类蛋黄酱乳液的结晶凝固点降低(-18→-28℃),而蛋黄酱即使具有低于冷冻温度(-20℃)的结晶凝固点(-27.89℃),仍发生了冻融破乳现象,类蛋黄酱乳液较好的界面稳定性赋予了其较好的冻融稳定性,为开发一类天然低胆固醇高冻融稳定性的酱类乳液提供了研究基础。

In this paper,the hydrodynamic particle size(Dh),zeta-potential(ζ),surface hydrophobicity(H0),and solubility of the acid-heat-induced soy protein isolate aggregates(AHSPI)were characterized and measured,and the acidic(pH 3.0)native soy protein isolate particles(ANSPI),the pH 7.0 heat-induced soy protein isolate aggregates(HSPI)were used as the comparative analysis.At the same time,AHSPI was selected to prepare mayonnaise-like emulsions with high freeze-thaw stability.The effects of different protein concentrations on the appearance,microstructure,viscoelasticity,and DSC thermal analysis of mayonnaise-like emulsions were discussed.The results indicated that the hydrodynamic particle size of AHSPI(204.67 nm)and H0(79418)were larger than ANSPI and HSPI(pH 7.0),but the absolute value of zeta-potential(35.93 mV)was smaller than that of ANSPI and HSPI(pH 7.0),and the solubility(89.47%)was better than HSPI(pH 7.0).The minimum concentration of mayonnaise-like emulsions prepared by AHSPI after 3 freeze-thaw cycles was 0.3 wt%.The structure of the emulsions remained the same after freeze-thaw,only the droplet size of the emulsions slightly increased.The rheological properties indicated that mayonnaise-like emulsions had the elastic gel network structure.With the increase of protein concentration,the droplet size of the emulsions gradually decreased,and the viscoelastic properties were enhanced.The DSC thermal analysis indicated that the freezing point of the mayonnaise-like emulsions decreased(-18→-28℃)when the protein concentration increased,.Even the freezing point(-27.89℃)of the mayonnaise was below the freezing temperature(-20℃),the demulsification of the mayonnaise still existed.The mayonnaise-like emulsions had better interfacial stability than mayonnaise,which had good freeze-thaw stability.This finding provides a research basis for the development of the low-cholesterol native sauce emulsions with high freeze-thaw stability.