Wang Xu, Xiong Youling L, Sato Hiroaki
Department of Animal and Food Sciences, University of Kentucky , Lexington, Kentucky 40546, United States.
Institute of Food Sciences and Technologies, Food Products Division, Ajinomoto Company, Inc. , Kawasaki 201-8681, Japan.
J Agric Food Chem. 2017 Sep 27;65(38):8451-8458. doi: 10.1021/acs.jafc.7b03007. Epub 2017 Sep 18.
Porcine myofibrillar protein (MP) was modified with glucose oxidase (GluOx)-iron that produces hydroxyl radicals then subjected to microbial transglutaminase (TGase) cross-linking in 0.6 M NaCl at 4 °C. The resulting aggregation and gel formation of MP were examined. The GluOx-mediated oxidation promoted the formation of both soluble and insoluble protein aggregates via disulfide bonds and occlusions of hydrophobic groups. The subsequent TGase treatment converted protein aggregates into highly cross-linked polymers. MP-lipid emulsion composite gels formed with such polymers exhibited markedly enhanced gelling capacity: up to 4.4-fold increases in gel firmness and 3.5-fold increases in gel elasticity over nontreated protein. Microstructural examination showed small oil droplets dispersed in a densely packed gel matrix when MP was oxidatively modified, and the TGase treatment further contributed to such packing. The enzymatic GluOx oxidation/TGase treatment shows promise to improve the textural properties of emulsified meat products.
用葡萄糖氧化酶（GluOx）-铁对猪肌原纤维蛋白（MP）进行修饰，该组合会产生羟基自由基，然后在4℃下于0.6M氯化钠中进行微生物转谷氨酰胺酶（TGase）交联。检测由此产生的MP聚集和凝胶形成情况。GluOx介导的氧化通过二硫键和疏水基团的封闭促进了可溶性和不溶性蛋白质聚集体的形成。随后的TGase处理将蛋白质聚集体转化为高度交联的聚合物。用这种聚合物形成的MP-脂质乳液复合凝胶表现出显著增强的凝胶化能力：与未处理的蛋白质相比，凝胶硬度提高了4.4倍，凝胶弹性提高了3.5倍。微观结构检查表明，当MP被氧化修饰时，小油滴分散在紧密堆积的凝胶基质中，而TGase处理进一步促进了这种堆积。酶促GluOx氧化/TGase处理有望改善乳化肉制品的质地特性。
