CONICET | Buscador de Institutos y Recursos Humanos

Green tea polyphenols are valuable compoundspossessing antioxidant and antiproliferative activities. Unfortunately, polyphenolsare also responsible for the undesired sensorial properties, especiallyastringency and bitter taste, which limits their use in food products. Tocircumvent this drawback, delivery systems have been developed, and among them,encapsulation would appear to be a promising approach. The objective is to bindpolyphenols to whey proteins and gelatin in order to mask or reduce theirastringency and bitter taste without affecting their biological activity. Firstly,polyphenols (0.5% wt) were combined with whey proteins (3% wt) at pH 6, and thecomplexes obtained were tested in their antioxidant and antiproliferativeactivity. Results showed that this spontaneous binding did not affect nor theirantioxidant activity neither their antiproliferative activity. Furthermore,these activities were evaluated before and after an in vitro digestion. Results demonstrated that both, antioxidant andantiproliferative activities were not affected by the presence of whey proteinsand even better activities were observed after digestion. These could beexplained by the antioxidant and antiproliferative activities of the peptidesgenerated from whey proteins after digestion. Thus, in order to improve themasking effect of whey proteins over polyphenols astringency, gelatin was addedto the system and assessed at 0.05, 0.1 and 0.25 %wt. Results showed thatparticle mean diameter increased with the increment of gelatin concentration:84, 167 and 257 nm for 0.05, 0.1 and 0.25 %wt, respectively. Samples showed novariations in size during the storage indicating that particles are stable overtime. We concluded that the protein combination selected was adequate toencapsulate polyphenols due to the spontaneous formation and stability of theparticles. This system would be useful for the development of a bioactivecontaining ingredient such as polyphenols.