Sucrose Concentration and Fermentation Temperature Impact the Sensory Characteristics and Liking of Kombucha

Abstract

Kombucha is a fermented tea beverage consumed for its probiotics and functional properties. It has a unique sensory profile driven by the properties of tea polyphenols and fermentation products, including organic acids. Fermentation temperature and sucrose content affect the fermentation process and the production of organic acids; yet less is known about their impacts on the sensory profile and consumer acceptance. Thus, we aimed to examine the impact of sucrose concentration and fermentation temperature on sensory attributes and liking. For this study, kombucha tea was fermented at three different concentrations of sucrose and fermented at two temperatures for 11 days. Fermentation was monitored by pH, brix, and titratable acidity, and consumers (n = 111) evaluated the kombucha for sensory attributes and overall liking. The fermentation temperature resulted in significant differences in titratable acidity, with higher temperatures producing more organic acids, resulting in higher astringency, and suppressed sweetness. The lower fermentation was reported as significantly more liked, with no difference in liking between the 7.5% and 10% sucrose kombucha samples. Fermentation temperature had the greatest impact on the sensory profile rather than sucrose concentration, which had a greater effect on the fermentation rate and production organic acids.

Keywords: fermentation; fermented tea; physical analysis; sensory analysis; titratable acidity.

Figure 1

Measurements (mean ± SD) for (a) pH, (b) Brix, and (c) titratable acidity throughout the 11-day fermentation period.

Figure 1

Measurements (mean ± SD) for (a) pH, (b) Brix, and (c) titratable acidity throughout the 11-day fermentation period.

Figure 2

Mean liking scores (±SEM) for kombucha with 5%, 7.5% and 10% (w/v) fermented at (a) 20 °C and (b) 30 °C.

Figure 3

Sensory profile of the kombucha beverages fermented at 20 °C and 30 °C (lines: dashed and solid) with 5%, 7.5%, and 10% sucrose (colors: green, orange, purple). Mean intensity ratings reported on general visual analog scale (gVAS) for eight flavor attributes.

Figure 4

A comparison between mean sourness intensity ratings (±SEM) and total titratable acidity (g/L) for kombucha samples. Intensity ratings were collected using a gVAS, general visual analog scale. Different shapes represent temperature (20 °C, circle and 30 °C, triangle) and different colors represent sucrose concentration (5%, green; 7.5%, orange; and 10%, purple).