Grape pomace – possible antioxidant and microbial quality enhancement for pork sausages

Grape pomace (GP), a wine industry by-product, offers a sustainable approach to meat preservation. This study assessed GP extracts and powders (Cabernet Franc, Merlot) in pork sausages during 21 days of refrigerated storage. The total polyphenol content of GP extracts reached 12.11 ± 1.36 mg GAE.g -1 (Cabernet Franc) and 7.58 ± 2.15 mg GAE g -1 (Merlot), with strong antioxidant activities confirmed by DPPH, FRAP, and ABTS assays. Sausages with GP exhibited significantly lower lipid oxidation, with TBARS values reduced from 0.346 ± 0.013 mg MDA kg -1 in controls to 0.264–0.292 mg.kg -1 in GP treatments on day 21. Merlot extract lowered total viable counts (2.85 ± 0.01 log CFU.g -1 ) compared to control samples (2.97 ± 0.01 log CFU.g -1 ). GP powder increased oleic acid (44.07 ± 0.85%) and linoleic acid (12.59 ± 0.31%) contents, while also elevating fat and reducing protein and water proportions in sausages. Extracts, in contrast, had minimal effect on composition. Overall, GP—particularly extracts—enhanced oxidative stability, microbiological quality, and fatty acid profile while supporting by-product valorization and clean-label, sustainable food production.