Collagen and Keratin Hydrolysates to Delay the Setting of Gypsum Plaster

Exploring non-covalent interactions of β-casein with six polyphenols

β-casein is a promising delivery agent for polyphenols that protect their bioactivity. However, limited evidence has been reported on their optimal combination ratios of polyphenols with β-casein and elucidated the factors affecting their interactions. Herein, correlation analysis was used to study the impact of structural, physical, and chemical properties of six polyphenols that are found in abundance in fruits, on their interactions with β-casein, following multi-spectroscopy analysis of optimal molar concentration ratio evaluation. Quenching efficiency was primarily positively influenced by polyphenol molecular weight to its number of hydroxyl groups ratio. Interactions of flavonoids with β-casein were positively affected by their hydrophobicity, whereas phenolic acids were negatively correlated to their charge. The optimal polyphenol to β-casein molar ratio was at or below 20:40. Our findings contribute to an enhanced comprehension of the mechanisms governing milk protein-polyphenol interactions, facilitating the cost-effective applications of polyphenols across food and pharmaceutic industries.

Preferential Binding of Polyphenols in Blackcurrant Extracts with Milk Proteins and the Effects on the Bioaccessibility and Antioxidant Activity of Polyphenols

Milk proteins are well-known delivery agents; however, there is no clear understanding of the competitive interactions of milk proteins with polyphenols in mixed complex systems. Here, we investigate the preferential competitive interactions of different polyphenols present in blackcurrant extract with milk proteins by quantifying the protein-bound polyphenols and comparing the factors affecting these interactions. In addition, bioaccessibility and antioxidant activity were studied after in vitro gastric digestion. Our results indicated that polyphenols from blackcurrant extracts were preferentially bound to caseins more than whey proteins, with noncovalent interactions causing secondary structural changes in the protein. The hydrophobicity and the charge of the polyphenols were negatively and positively related to the number of polyphenols bound to casein and whey proteins, respectively. Moreover, the bioaccessibility and antioxidant activity of polyphenols were enhanced in the presence of milk proteins in milk-based blackcurrant samples when compared to polyphenol and protein-alone samples in the in vitro gastric phase. These findings underscore the critical role of milk proteins in encapsulating or delivering polyphenols. This will pave the way for boosting the bioavailability of polyphenols by complexing them with milk proteins and formulating functional dairy foods, integrating the beneficial effects of these compounds.