Antioxidant and Antimicrobial Activity of Commercial Propolis Extract in Beef Patties
Journal of Food Science, Early View
The objective of this study was to evaluate the efficacy of propolis extract (PE) to reduce lipid oxidation and microbial growth on beef patties during refrigerated storage. Beef patties were manufactured by incorporating PE in 4 different treatments: (1) Control (no PE addition); (2) commercial propolis 1 (2% w/w; CP1); (3) commercial propolis 2 (2% w/w; CP2); and (4) noncommercial propolis (2% w/w; NCP). Raw patties were wrapped with polyvinyl chloride and stored at 2 °C for 8 d.
Total phenolic content (TPC), free-radical scavenging activity (FRS), and polyphenolic content of the PE were evaluated using high-performance liquid chromatography (HPLC). Lipid oxidation (thiobarbituric acid-reactive substances (TBARS), conjugated dienes (CnDs), metmyoglobin (MetMb%), pH variation, and color (L*, a*, b*, C*, and h*), and microbial growth (mesophilic and psychrotrophic bacteria) of patty samples were measured. NCP treatment demonstrated the highest FRS (64.8% at 100 μg/mL), which correlated with TPC and the presence of polyphenolic compounds.
Lipid oxidation (78.54%, TBARS; 45.53%, CnD; 58.57%, MetMb) and microbial mesophilic and psychrotrophic growth (19.75 and 27.03%, respectively) values were reduced by NCP treatment in refrigerated samples after 8 d. These results indicate that PE has great potential as a natural antioxidant and antimicrobial additive to extend the shelf life of beef patties.
In this work, the results indicate that propolis reduced lipid oxidation and microbial growth, thereby extending meat sample shelf life. Propolis should be considered for use as an alternative to commercially available antioxidants that are currently used in meat products.