高压均质处理对不同浓度肌原纤维蛋白水悬液理化特性及蛋白结构的影响

以鸡肉中的肌原纤维蛋白(Myofibrillar proteins,MP)为对象,研究103 MPa压力条件下高压均质(High pressure homogenization,HPH)对不同浓度(5、10、15 mg/mL)MP水悬液理化性质和蛋白结构的影响。结果表明:HPH可以显著提高不同浓度MP在水中的溶解性(P<0.05),改善MP水悬液的分散性、流变性等理化特性,破坏蛋白结构。随着MP浓度增加,MP水悬液溶解度下降、稳定性变差(P<0.05);高浓度的MP在HPH处理过程中可能会发生蛋白聚集,导致水悬液中蛋白粒径增大,表观粘度变大,流动性降低;MP水悬液二、三级结构改变,表面疏水性降低,巯基含量上升,α-螺旋增加,β-折叠下降,从而影响其溶解性;其中5 mg/mL的MP水悬液经过HPH处理后溶解性较好,溶解度达到88.39%,在4 ℃条件下放置9 d后仍然能保持79.08%的溶解度。本研究为食品行业中肉蛋白的深加工提供了参考依据。

Effects of High Pressure Homogenization on Physicochemical Properties and Protein Structure of Myofibrillar Protein Aqueous Suspensions with Different Concentrations

Chicken myofibrillar proteins(MPs)were used to study the effects of high pressure homogenization(HPH)on the physicochemical properties and protein structure of MP water suspension with different concentrations(5,10,15 mg/mL)under 103 MPa pressure.The results showed that,HPH could significantly improve the solubility of MP in water at different concentrations(P<0.05),improve the dispersion and rheological properties of MP water suspension,and destroy the protein structure. With the increase of MP concentration,the solubility and stability of MP water suspension decreased(P<0.05). Protein aggregation might occur during HPH treatment of high concentration MP,which resulted in the increase of protein particle size,the increase of apparent viscosity and the decrease of fluidity in water suspension. The secondary and tertiary structure of MP water suspension changed,the surface hydrophobicity decreased,the content of sulfhydryl group increased,the α-helix increased and the β-folding decreased,which affected the solubility of MP water suspension. The solubility of MP water suspension of 5 mg/mL was better after HPH treatment,which reached 88.39%. The solubility of MP water suspension was still 79.08% after 9 d at 4 ℃. This study provided a reference for the further processing of meat protein in food industry.