Lou Xiaowei, Yang Qiuli, Sun Yangying, Pan Daodong, Cao Jinxuan
Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, Ningbo University, Ningbo, China.
J Sci Food Agric. 2017 Sep;97(12):3917-3922. doi: 10.1002/jsfa.8325. Epub 2017 May 8.
In order to investigate the influence of non-thermal effects of microwaves on the flavour of fish and meat products, the G-actin of grass carp in ice baths was exposed to different microwave powers (0, 100, 300 or 500 W); the surface hydrophobicity, sulfhydryl contents, secondary structures and adsorption capacity of G-actin to ketones were determined.
As microwave power increased from 0 to 300 W, the surface hydrophobicity, total and reactive sulfhydryls increased; α-helix, β-sheet and random coil fractions turned into β-turn fractions. As microwave power increased from 300 to 500 W, however, hydrophobicity and sulfhydryl contents decreased; β-turn and random coil fractions turned into α-helix and β-sheet fractions. The tendencies of adsorbed capacity of ketones were similar to hydrophobicity and sulfhydryl contents.
The increased adsorbing of ketones could be attributed to the unfolding of secondary structures by revealing new binding sites, including thiol groups and hydrophobic binding sites. The decreased binding capacity was related to the refolding and aggregation of protein. The results suggested that microwave powers had obvious effects on the flavour retention and proteins structures in muscle foods. © 2017 Society of Chemical Industry.
为了研究微波非热效应对鱼和肉制品风味的影响，将冰浴中的草鱼G-肌动蛋白暴露于不同微波功率（0、100、300或500W）下；测定了G-肌动蛋白的表面疏水性、巯基含量、二级结构以及对酮类的吸附能力。
随着微波功率从0增加到300W，表面疏水性、总巯基和活性巯基增加；α-螺旋、β-折叠和无规卷曲比例转变为β-转角比例。然而，当微波功率从300W增加到500W时，疏水性和巯基含量降低；β-转角和无规卷曲比例转变为α-螺旋和β-折叠比例。酮类的吸附能力趋势与疏水性和巯基含量相似。
酮类吸附增加可能归因于二级结构的展开，暴露出包括巯基和疏水结合位点在内的新结合位点。结合能力降低与蛋白质的重新折叠和聚集有关。结果表明，微波功率对肌肉食品中的风味保留和蛋白质结构有明显影响。©2017化学工业协会。
