Antioxidant Activity and Peptide Levels of Water-Soluble Extracts of Feta, Metsovone and Related Cheeses

The purpose of the present study was to evaluate the antioxidant, anti-inflammatory activity and peptide levels of Feta cheese and other brined cheeses, and Metsovone cheese and other smoked cheeses. Feta, goat and cow cheeses are classified as brined. Feta cheese is made exclusively from ewe milk or ewe milk with the addition of a small amount of goat milk. Metsovone and other smoked cheeses are made from cow milk with a possible addition of small amounts of ewe and goat milk. The antioxidant activity was determined using Folin and FRAP assays, while the peptide content was determined using Bradford and Lowry assays. The anti-inflammatory activity was assessed using the lipoxygenase inhibition assay. The assays were applied in the water-soluble extract of cheeses. The results showed that Feta cheese and brined cow cheese differed in antioxidant activity. Feta cheese and brined goat cheese also differed in both antioxidant activity and peptide levels. Specifically, Feta cheese had higher antioxidant activity in comparison with both goat and cow cheeses. As for peptide content, Feta cheese had a higher peptide level compared to goat cheese. The results also showed that Metsovone cheese and other smoked cheeses exhibited significant antioxidant activity and peptide levels. Moreover, the water-soluble extracts of all cheeses showed some anti-inflammatory activity.