PERCOLATED ILEX PARAGUARIENSIS EXTRACT AS A CLEAN-LABEL ANTIOXIDANT: ENHANCING OXIDATIVE STABILITY AND FUNCTIONAL QUALITY OF FRESH PORK SAUSAGES

The growing demand for clean-label foods has encouraged the replacement of synthetic additives with natural antioxidants in meat products. In this context, Ilex paraguariensis (yerba mate), recognized for its high phenolic content and antioxidant activity, represents a promising alternative for improving the oxidative stability of fresh sausages. This study evaluated the effects of yerba mate extracts on the oxidative stability and technological characteristics of fresh pork sausages during refrigerated storage. Yerba mate was obtained from a distributor (Tereré 2000). The percolated extract was obtained from 150 g of dried leaves and 650 mL of 70°GL hydroethanolic solution using a percolation column at 21.6 ± 1.0 mL/min, followed by rotary evaporation and spray drying at 175°C inlet and 103°C outlet temperatures. The commercial extract was donated by Duas Rodas. Both extracts were stored at -18 ± 1°C and incorporated into the formulations at 0.2%. Curing salts were used as the conventional treatment due to their contribution to color stabilization and oxidative and microbiological control. Four treatments were prepared: control without antioxidants (CFS), conventional formulation with curing salts (TFS), formulation with percolated yerba mate extract (PEFS), and formulation with commercial yerba mate extract (CEFS). The extracts were characterized for particle size distribution, Fourier-transform infrared spectroscopy, thermal properties, total phenolic content, and antioxidant activity. The sausages were stored at 4 ± 1°C and evaluated for physicochemical characteristics, water-holding capacity, lipid oxidation (TBARS), microbiological quality, sensory attributes, and phenolic bioaccessibility after in vitro gastrointestinal digestion. Bioaccessibility was expressed as the percentage of phenolic compounds recovered in the intestinal phase relative to the gastric phase. The percolated extract exhibited smaller and more homogeneous particles, whereas the commercial extract showed a broader particle size distribution and a higher incidence of fractured particles. During storage, pH and water activity did not differ significantly among treatments. The incorporation of the extracts did not negatively affect color stability or technological properties, with moisture being the only significantly affected parameter. TBARS values remained below the sensory perception threshold (2 mg MDA/kg), and sausages containing the extracts showed lower lipid oxidation than the control. The percolated extract exhibited antioxidant performance comparable to the conventional formulation with curing salts. Phenolic bioaccessibility was influenced by thermal processing, with the percolated extract showing the greatest functional potential. Ilex paraguariensis extract, particularly when obtained by percolation, represents a promising natural antioxidant for partially replacing conventional antioxidants while maintaining the oxidative stability and technological quality of fresh pork sausages during refrigerated storage.

Acknowledgement

Authors would like to thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ); the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); and COMCAP/UEM.