The changes and gastric digestive properties of gel were investigated for oxidiz ed myofibrillar protein(MP)(0–1 mmol/L H_(2)O_(2))treated by 30%substitution of NaCl with KCl,MgCl_(2),and KCl/MgCl_(2).Mild oxidation ...The changes and gastric digestive properties of gel were investigated for oxidiz ed myofibrillar protein(MP)(0–1 mmol/L H_(2)O_(2))treated by 30%substitution of NaCl with KCl,MgCl_(2),and KCl/MgCl_(2).Mild oxidation level(0.3 mmol/L H_(2)O_(2))facilitated the protein unfolding,and MgCl_(2)obviously intervened the protein selfassembly by forming the salt bridge and more disulfide bonds.At the same oxidation concentration,the sodium-reduced MP substituted with KCl formed dense network structure with better gel strength(increased by 6%–18%)and water retention in comparision to the gel without sodium reduction.The KCl-substituted gel chewing work was also relatively higher among the low-sodium samples at the first chewing cycle.Reversely,the relatively soft structure and lower gel viscosity in simulated oral chewing were found in MgCl_(2)-substituted gel.These changes decreased the contact limit between pepsin and protein for better gastric disintegration or pepsin diffusivity,and increased the proportion of small molecular weight peptides(25.83%,<5 kDa).Therefore,partial substitution of NaCl with other salt replacers could influence the physicochemical properties of low-sodium MP suspension or gel under different oxidation degree and the subsequent gastric digestion characteristics.展开更多
基金supported by the National Natural Science Foundation of China(32172257)the Ministry of Science and Technology of the People’s Republic of China(DL2022163005L)+2 种基金the Science and Technology Program of Qingyuan(2022KJJH018)the Postdoctoral Innovative Talent Support Program(BX20230130)the 111 Project(B17018).
文摘The changes and gastric digestive properties of gel were investigated for oxidiz ed myofibrillar protein(MP)(0–1 mmol/L H_(2)O_(2))treated by 30%substitution of NaCl with KCl,MgCl_(2),and KCl/MgCl_(2).Mild oxidation level(0.3 mmol/L H_(2)O_(2))facilitated the protein unfolding,and MgCl_(2)obviously intervened the protein selfassembly by forming the salt bridge and more disulfide bonds.At the same oxidation concentration,the sodium-reduced MP substituted with KCl formed dense network structure with better gel strength(increased by 6%–18%)and water retention in comparision to the gel without sodium reduction.The KCl-substituted gel chewing work was also relatively higher among the low-sodium samples at the first chewing cycle.Reversely,the relatively soft structure and lower gel viscosity in simulated oral chewing were found in MgCl_(2)-substituted gel.These changes decreased the contact limit between pepsin and protein for better gastric disintegration or pepsin diffusivity,and increased the proportion of small molecular weight peptides(25.83%,<5 kDa).Therefore,partial substitution of NaCl with other salt replacers could influence the physicochemical properties of low-sodium MP suspension or gel under different oxidation degree and the subsequent gastric digestion characteristics.
