The impact of fermentation duration on pH, antioxidant properties and consumer preference of Spirulina sp. beverage

Fermentation enhances the nutritional value of antioxidants in food. Fermentation breaks down the cell wall structure of the ingredients and activates enzymes that release bound compounds, such as antioxidant phenolics. This study aimed to assess the effect of fermentation time on Spirulina sp. regarding antioxidant activity, pH, consumer preference and low molecular weight bioactive compounds. The results showed that the best fermentation time was the first day with the highest antioxidant activity of 86.82 % a pH value of 4.76; phytochemical screening analysis indicated the presence of positive compounds from the flavonoid, alkaloid, steroid, triterpenoid, catechol and phenolic groups; total phenolic content of 147.548 µg/ml; presence of 9 essential amino acids and seven non-essential amino acids; consumer preference level of 7.22 < µ < 7.50; and the primary low molecular weight bioactive compound is hexadecenoic acid with an area of 55.77 %. The findings indicated that beverages fermented with Spirulina sp. possess the potential to serve as promising health-functional beverages, given their abundance of active compounds that are advantageous to health.