Effect of Addition of Grape Pomace Extract (Pinot Noir Variety) on the Physical-Chemical Properties and Safety of Frankfurter Sausages

This study was designed to demonstrate the effect of Pinot Noir grape pomace extract (GPE) on the quality and shelf-life of frankfurter sausages during 35 days of storage at 4 °C. Due the high polyphenolic compounds of GPE, there is an increasing interest in potentially replacing the artificial additives with natural alternatives generated from waste. The GPE was prepared using ultrasound-assisted extraction (UAE). Following ultrasound-assisted extraction, the extracts were filtered through filter paper to remove solid residues. The meat batter was divided into four groups: control (NFC) and three experimental batches with 1%, 2%, and 3% Pinot Noir grape pomace extract (FE1, FE2, FE3). Results showed that increasing GPE significantly raised water and protein levels while reducing fat content and water activity (p < 0.05). Except for a decrease in the b* color value, GPE did not notably affect pH, collagen, or L* and a* color parameters. Although the chemical parameters changed, the collagen content remained unchanged, indicating that GPE does not significantly affect connective tissues. The best effect was shown in the sample FE3, which had the highest GPE addition and exhibited the highest protein content (16.46%) and moisture content (64.99%), as well as the lowest water activity (0.93). Microbiologically, GPE reduced aerobic mesophilic bacteria, with all samples remaining safe for up to 28 days. These findings confirm GPE as a viable ingredient for producing safe, high-quality frankfurter sausages.