Water kefir was fermented with microalga biomass addition.
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Spirulina biomass is an alternative carbohydrate source for fermenting water kefir.
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Water kefir nutritional value was enhanced by Spirulina supplementation.
Abstract
This study evaluated the fermentation of water kefir with the addition of Spirulina biomass to replace the sugar. The kefir was evaluated for protein, lipid, fatty acid (FA), and phycocyanin content. Kefir was fermented (48 h, 25 °C) using Spirulina (1.6 and 2.4 g); the control assay was performed without Spirulina. After fermentation, the assay with 2.4 g yielded the higher growth rate; 14% and 32.7% more than obtained with less amount of Spirulina and control assay, respectively. Moreover, this condition yielded the highest protein content (48.09%). Fermentation affected the FA composition, since C16:0, C18:0 and C18:2n6c amounts were higher than in control. This study was the first to evaluate Spirulina in water kefir grain fermentation. Spirulina biomass was found to be an alternative to other carbohydrate sources, and it increased product's nutritional value. In addition to the metabolism of FA by kefir microorganisms, decreasing their concentration in the final fermented product.
