Researchers from IRTA and URV produce healthier peach and grape juices by using wine by-products

Wine lees are a by-product of the winemaking process. Although considered waste, they are rich in bioactive compounds such as polyphenols, which have antioxidant and antimicrobial properties. Their utilization, along with the discarded peach pulp from juice production processes, led research teams from the Rovira i Virgili University (URV) and the Institute of Agrifood Research and Technology (IRTA) to explore ways to use these by-products as functional ingredients. In their study, published in the scientific journal Foods and part of Virginia Prieto's thesis at IRTA, they successfully enhanced the antioxidant and antimicrobial effects of peach and grape juices.

During the study, wine lees were incorporated into fresh peach and grape juices at concentrations of 1.5% and 2% and stored under refrigeration. Maribel Abadias, from the Processed Fruits and Vegetables Group of the Postharvest Program at IRTA, notes:

"As a result of this process, the growth of Listeria monocytogenes, one of the most concerning pathogens in ready-to-eat refrigerated products, was significantly reduced."

The results also showed a significant increase in polyphenol content (by 75%), the antioxidant activity of these juices (by 75%), and the total soluble solids content by 10%. Additionally, during refrigerated storage, the functional juice maintained stable properties such as pH and acidity.

Miquel Mulero, a researcher from the Nutrigenomics Research Group in the Department of Biochemistry and Biotechnology at URV, who worked together with the IRTA group at the Fruitcentre in Lleida, emphasizes:

"These results suggest that this functional juice could have a longer shelf life and offer health benefits due to its bioactive compounds."

The research also included a sensory evaluation, in which 57% of the tasters positively rated this new functional juice. However, the research team highlights the potential of these wine by-products as functional ingredients and natural antioxidants.

Francisca Isabel Bravo, a researcher from the Nutrigenomics research group at URV, points out:

"This new product, which extends the shelf life of fresh peach and grape juice and adds nutritional value, represents an opportunity to valorize a by-product of the wine industry within the framework of the circular economy."

Moreover, it offers an opportunity for local stone fruit producers to increase the economic value of these products, contributing to greater sustainability in agricultural and food production.

The study underscores the importance of further research to fully identify the bioactive compounds in wine lees to explore the potential of their properties in developing new innovative functional food products.

Source: URV

Publication:

Prieto-Santiago, V.; Aguiló-Aguayo, I.; Bravo, F.I.; Mulero, M.; Abadias, M. Valorization of Peach Fruit and Wine Lees through the Production of a Functional Peach and Grape Juice. Foods 2024, 13, 1095. https://doi.org/10.3390/foods1307109