Abstract:The effects of resistant starch on the in vitro digestibility and gel properties of sodium pyrophosphate-modified myofibrillar protein (SPPMP) emulsion were investigated to provide theoretical basis for further application of resistant starch in meat products. In this study, pea resistant starch was prepared by gelatinization-ultrasonic-retrogradation method, and added into the SPPMP emulsion in the proportion of 0%, 2%, 4% and 6%, respectively. The effects of pea resistant starch on the emulsion stability, in vitro digestibility, rheological properties and gel characteristics of SPPMP emulsion were investigated. Results showed that C-O-P bonds were formed by phosphorylation, which promoted formation of three-dimensional network of heat-induced gel, and improved the apparent viscosity, storage modulus (G′), gel hardness and elasticity, gel strength and gel water holding capacity of MP emulsion. When pea resistant starch was further added, the final in vitro digestibility of protein still remained 93.80% of the original protein digestibility, and the rheological and gel properties of the emulsion were further improved. The G′, gel strength and water holding capacity of the emulsion were 21.61 times, 2.40 times and 1.44 times of the original protein, respectively, when 6% of pea resistant starch was added. This may be explained by that the introduction of phosphate groups induced the cross-link of protein molecules via ion interaction, and the 'filling effect' of pea resistant starch promoted formation of a tighter network structure of MP, which ultimately improved the properties of the emulsion gel. The combination of resistant starch and phosphorylation modification can improve the processing properties of meat protein without obviously reducing the nutritional value of protein.