CONICET | Buscador de Institutos y Recursos Humanos

The interest of studying polyphenolic compounds has increased during the last few years due to their antioxidant properties and their role in the prevention of several diseases. Polyphenolic compounds are sometimes added to probiotic dairy products as a method to enhance the beneficial health effects of these functional foods. During winemaking, grape pomace residue is generated creating a heavy environmental impact. It was shown that grape pomace is a good source of phenols. For these reasons, probiotic fermented skim milk, containing Streptococcus thermophilus TA040 and Lactobacillus acidophilus LAC4, was supplemented with pomace extracts of Pinot Noir, Freisa, Croatina, and Barbera Italian grape varieties. After supplementation with Pinot Noir pomace, there was a significant increase in the maximum acidification rate compared to fermented skim milk without any supplementation. The time necessary to reach pH 4.5, considered the endpoint of fermentation, was shortened when all grape pomace extracts were added to the fermented skim milk. It was also observed that the polyphenolic compound supplementations had a positive effect on cell viability of both bacteria strains during 28 days of storage at 4 ºC. The results of this current study as a whole suggest that the addition of grape pomace polyphenols could be employed in developing novel functional dairy products that could satisfy the interest of consumers seeking products that combine nutritional quality, environmental sustainability and health benefits. In a technological context, this work showed that grape pomace extracts supplementation decreased the fermentation time and increased the viability of probiotic bacteria which would reduce the costs in large scale fermentations.