预热处理金针菇蛋白对猪肉肌原纤维蛋白凝胶特性的影响

Effects of preheat treatment Flammulina filiformis protein on the properties of pork myofibrillar protein gel

本文研究预热处理(preheat treatment,PT)金针菇蛋白(Flammulina filiformis protein,FFP)对肌原纤维蛋白(myofibrillar protein,MP)凝胶特性的影响。试验将FFP在65、75、85和95℃下分别预热处理30、60、90和120min,以蛋白溶解度、总巯基含量和表面疏水性为指标,确定FFP预热处理的最佳温度与时间;将预热处理的FFP(PT-FFP)与MP以不同的比例(0:10、1:9、2:8、3:7、4:6,M/M)混合制备复合凝胶(总蛋白质量浓度均为40mg/mL),以凝胶强度、持水性、流变学特性与微观结构为指标,考察PT-FFP对MP凝胶特性的影响。结果表明,75℃预热处理60min,FFP的溶解度与表面疏水性最高,总巯基含量最低,故确定该预热处理条件为最佳;将该条件下制备的PT-FFP以不同比例与MP混合制备凝胶,结果发现PT-FFP比FFP更有利于复合凝胶的凝胶强度和持水性的提高(P<0.05),特别是当PT-FFP与MP混合比例为1:9时,复合凝胶的凝胶强度和持水性达到最高值121.38g和85.25%;流变学结果也表明,PT-FFP能够提高复合凝胶的弹性模量G′和损耗模量G″;电镜观察可以看出PT-FFP与MP复合的凝胶具有更强的连续性,结构更为致密。总之,经过75℃预热处理60min后的FFP和MP以1:9混合时能够改善肌原纤维蛋白凝胶特性和流变学特性。

The effect of preheat treatment(PT)Flammulina filiformis protein(FFP)on the gel properties of myofibrillar protein(MP)was investigated.FFP was preheated at a series of temperature(65,75,85 and 95℃)for different time(30,60,90 and 120min),respectively.The optimal temperature and time were determined based on protein solubility,total sulfhydryl content and surface hydrophobicity.Preheat treatment FFP(PT-FFP)was mixed with MP at different ratios(0:10,1:9,2:8,3:7,4:6,M/M)to prepare mixed gels with total protein concentration of 40mg/mL.The effects of PT-FFP on MP gel properties were investigated on the basis of gel intensity,water holding capacity,rheological properties and microstructure.The results showed that solubility and surface hydrophobicity of FFP were the highest and the total sulfhydryl content was the lowest when FFP was preheated at the optimum of 75℃ for 60min.PT-FFP prepared under the optimum condition was then mixed with MP at different ratios to prepare gels.It was found that PT-FFP well improved the gel intensity and water holding capacity of the mixed gels as compared with untreated FFP(P<0.05).Notably,the gel intensity and water holding capacity of the mixed gels reached the highest values of 121.38g and 85.25%respectively at the PT-FFP and MP mixed ratio of 1:9.The rheological results also showed that PT-FFP increased the elastic modulus G′and loss modulus G″of the mixed gel.Scanning electron microscope observation showed that the gel of PT-FFP mixed with MP had stronger continuity and more dense structure.In summary,FFP pre-treated at 75℃ for 60min mixed with MP could improve the gel properties and rheological properties of myofibrillar protein at the mixed ratio of 1:9.