Abstract

The aim of the present study was to evaluate the effect of the inoculation of the heated aqueous red beetroot extracts (30, 50 and 60°C) by different concentrations ofSaccharomyces cerevisiae (0.50, 0.75 and 1.00%). The optimum experimental temperature value and S. cerevisiae concentration were found to be 50°C and 0.50% for both sugar consumption and pigment preservation. The antioxidant capacity measured by ABTS^•+ assay (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation) shows that this extract present an appreciable activity (EC₅₀= 10.77 µg.mL^-1) above the tested samples. The betalains compounds were analyzed and identified using UPLC LTQ Orbitrap MS method. Betalains (vulgaxanthin I, betanin, isobetanin, betanidin and neobetanin) were determined in the fermented extract.

Key words: Red beetroot, fermentation, Saccharomyces cerevisiae, betalain compounds.