Effect of Mentha spicata L. and Artemisia campestris Extracts on the Shelf Life and Quality of Vacuum-Packed Refrigerated Sardine (Sardina pilchardus) Fillets

The present study investigated the effects of ethanolic extracts obtained from Mentha spicata and Artemisia campestris on the shelf life and the quality of vacuum-packed sardine fillets stored at 3 +/- 1 degrees C for a period of 21 days. The three groups were tested were VC, control group; VM, group treated with 1% mint extract; and VA, group treated with 1% artemisia extract. The observed shelf life of sardine fillets was 10 days for control samples, whereas the combination of vacuum packaging with mint and artemisia extracts extended the product's shelf life to 17 days. Among the chemical indices determined, the thiobarbituric acid-reactive substances values were significantly lower in VM samples. Total volatile base nitrogen was maintained at low levels in VA samples until 17 days of chilled storage. Results of aerobic plate counts and coliform counts showed the existence of a reduced growth in VA group, whereas lactic acid bacteria did not show a significant difference among groups. Natural extract treatments combined with vacuum packaging showed lower microbiological and chemical indices, indicating that the presence of phenolic compounds in mint and artemisia extracts and the removal of oxygen in the pack retarded lipid oxidation and reduced the growth of microorganisms, which resulted in preventing spoilage and extending the product's shelf life.