Emulsifying properties development of pork myofibrillar and sacroplasmic protein irradiated at different dose: A combined FT-IR spectroscopy and low-field NMR study

The present study investigated the effect of different irradiation dose (0, 3, 5 and 7 kGy) on the emulsifying properties development of pork myofibrillar protein (MP) and sacroplasmic protein (SP). The results showed that emulsifying activities of SP was significantly impaired by the increasing irradiation dose, while that of MP were only observed to be significantly improved at 3 kGy irradiation (P < .05). The increasing irradiation dose caused the increase of SP carbonyl groups and the decrease of its sulfhydryl groups (P < .05), while 3 kGy irradiation decreased the carbonyl groups of MP and increased ζ-potential significantly (P < .05). LF-NMR results revealed that the water hydration in MP structure was dose-dependent. FT-IR data displayed that irradiation caused minor change of SP in the amide I region from 1700 to 1600 cm−1, while ≥5 kGy irradiation significantly contributed to the denatured aggregated β-sheet components of MP.