Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology & Business University, Beijing 100048, China.
Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology & Business University, Beijing 100048, China.
Food Chem. 2023 Jun 1;410:135408. doi: 10.1016/j.foodchem.2023.135408. Epub 2023 Jan 5.
Monascus pigments (MPs) were adsorbed using calcium carbonate to produce CaCO-MPs lakes. The fundamental properties and formation mechanism of the lakes were investigated. Results indicated that CaCO displayed a high enough affinity for the MPs to form colorant lakes, while the MPs tended to transform the CaCO crystals from calcite to vaterite. The adsorption of MPs by CaCO followed the Freundlich isothermal model with n value higher than 1, confirming it as physical adsorption. The ΔG (-29 to ∼-33 kJ/mol) and ΔH(30-55 kJ/mol) indicated that lake formation was a spontaneous and endothermic process. UV/Vis spectroscopic analysis verified the complex formation between Ca and MPs via physical bonding, suggesting a possible attraction between the Ca and glutamate residues of the MPs. EDS showed that the MPs were trapped inside the particles. FTIR spectroscopy and XPS further confirmed that the physical bonding was the primary driving force behind the lake formation.
红曲色素(MPs)被碳酸钙吸附,形成 CaCO-MPs 色淀。研究了色淀的基本性质和形成机制。结果表明,CaCO 对 MPs 具有足够高的亲和力,形成了着色剂色淀,而 MPs 倾向于将 CaCO 晶体从方解石转变为文石。MPs 通过 CaCO 的吸附遵循 Freundlich 等温模型,n 值高于 1,证实这是一种物理吸附。ΔG(-29 至 ∼-33 kJ/mol)和 ΔH(30-55 kJ/mol)表明,色淀的形成是一个自发的吸热过程。UV/Vis 光谱分析验证了 Ca 与 MPs 之间通过物理键合形成复合物,表明 MPs 的 Ca 和谷氨酸残基之间可能存在吸引力。EDS 表明 MPs 被困在颗粒内部。FTIR 光谱和 XPS 进一步证实,物理键合是形成色淀的主要驱动力。