The effect of kefir enrichment with Arthrospira platensis and Chlorella vulgaris on kefir microbiota, antioxidant, and physicochemical properties

This study evaluated the effect of Arthrospira platensis and Chlorella vulgaris on kefir microbiota, total phenolic content, antioxidant activity, and physicochemical properties such as pH, Brix, total dry matter, and titratable acidity. The results showed that the addition of algae at concentrations of 0.5% (w/v) and 1% (w/v) to the kefir did not change the acceptable physicochemical properties of kefir. The acidity of the microalgae-enriched kefirs increased with increasing algae concentration. Total phenolic content and antioxidant activity of all kefir samples fortified with algae were higher than those of the control. However, the addition of A. platensis exhibited better prebiotic activity than C. vulgaris on kefir microbiota during storage. Principal component analysis and overall results showed that A. platensis was a better candidate for improving the nutritional value of kefir.