Structural characterization and emulsifier property of yeast mannoprotein enzymatically prepared with a β-1,6-glucanase
Yan Qiao, Chengyao Xia, Lin Liu, Lei Tang, Jihong Wang, Changsheng Xu, Juying Wang, Lei Zhang, Xianfeng Ye, Yan Huang, Dongmei Mao, Yongheng Liang, Zhoukun Li, Zhongli Cui
Abstract
Yeast cell wall mannoprotein with diverse structures and functions are effective emulsifiers due to the amphiphilic structure comprising a protein backbone and mannan chains. In this study, a β-1,6-glucanase-based approach to produce mannoproteins from baker's yeast was established. Batch production of mannoprotein MP112 was realized with 11.1% yield, 90.7% purity, and a mannan to protein ratio of 14.5. The mannan-protein conjugate structure was confirmed by composition analysis, FT-IR and NMR spectrometry, as well as SEM observation, and the assembled mesoporous structure with filamentous fibers was deduced to determine the favorable emulsifying properties from rheological analysis. Application of mannoprotein-based emulsion in the preparation of porcine myofibrillar protein gels showed that MP112 improves the properties of myofibrillar protein composite gels by the formation of a fine-stranded gel network with enhanced protein-polysaccharide-water interactions, which reduce damage to the muscle tissue and increase product quality. This study is expected to broaden the applications of mannoproteins as value-added ingredients.