Chemical Characteristic, Antioxidant Activity, and Consumer Acceptance Level of Kombucha from Sargassum cristaefolium Seaweed Tea

Seaweed infusion is a nutritious beverage rich in bioactive compounds, which is essential for human health. Enhancing the functional properties of seaweed tea can be achieved through the fermentation process to create kombucha. This research aims to explore the impact of fermentation duration on the chemical attributes, antioxidant capacity, and consumer preference of kombucha derived from Sargassum cristaefolium tea. The experimental approach involved varying fermentation periods, including no fermentation, 4, 8, 12, and 16 days of fermentation. Tests carried out included yield, water content, total phenol content, the antioxidant activity (through DPPH and FRAP methods), pH levels, total acidity, total reducing sugars, and sensory evaluation. The findings revealed that fermentation duration significantly influenced the chemical composition, antioxidant activity, and consumer acceptance. Notably, the 12-day fermentation period exhibited superior antioxidant activity compared to other treatments, showcasing a total phenolic content of 25.14±0.07 mg GAE/100 g, DPPH antioxidant activity of 83.00±0.83%, and FRAP antioxidant activity of 4.40±0.07 mM/g. Conversely, the optimal treatment in terms of chemical attributes and consumer preference for S. cristaefolium kombucha was observed with a 4-day fermentation period, yielding a pH of 3.07±0.02, total acidity of 1.20±0.07%, total reducing sugars of 2.86±0.34%, and hedonic ratings for color, aroma, taste, appearance, and overall quality at 4.18±0.76, 4.11±0.78, 4.40±0.72, 4.35±0.71, and 4.26±0.14, respectively.