Modulation of Myofibrillar Protein Emulsion Gels by Controlled Oxidized Chicken Fat: Conformational Structure, Gelation Performance and <i>in vitro</i> Digestion

The gel properties of myofibrillar proteins (MPs) emulsions were significantly affected by the oxidation state. In our study, the effect of chicken fat (CF) at different oxidation levels (0-1.2 h) on the conformational structure, intermolecular interaction and gelling performance of MP was investigated. Additionally, the functional characteristics of emulsified gels were explored by scanning electron microscopy (SEM) and in vitro digestion. The results showed that moderately oxidized CF could promote the transformation of α-helix to β-structure, enhanced hydrophobic interaction between proteins and increased the viscoelasticity of MPs gel. In contrast, over-oxidized CF would deteriorate the MPs gel network structure through protein aggregation. Finally, moderately oxidized CF (0.6 h) was used to facilitate the optimal MPs gel, whose gastrointestinal digestion capability increased by 6.85%. This study contributed to a comprehensive understanding of the modification of MPs by oxidized CF on the improvement of physicochemical properties, functional qualities of emulsified gels, which provided a new way of exploring the application of controlled oxidation oils in the emulsion-based meat products and even in the oil-rich meat production industry.