Effect of Ginger and Turmeric Ratio on the Physicochemical and Antioxidant of Kombucha

Lim, Mei Choo (2022) Effect of Ginger and Turmeric Ratio on the Physicochemical and Antioxidant of Kombucha. Final Year Project (Bachelor), Tunku Abdul Rahman University College.

Text Lim Mei Choo_Full Text.pdf Restricted to Registered users only Download (2MB)

Abstract

Kombucha is a type of a naturally fermented beverage rich in organic acids, bioactive compounds and probiotics, claimed to provide several health benefits such as antioxidant, anti-microbial and anti-carcinogenic. In this study, ginger, turmeric and blends of ginger and turmeric substrates were used as an alternative to black tea in traditional kombucha fermentation and changes of fermentation were observed for twelve days changes on its physicochemical and antioxidant. The antioxidant analysis demonstrated that the fermentation time and different substrates showed significant effects on the antioxidant activity. All the samples resulted in a significant increase in DPPH (free radicals scavenging activity), ferric reducing antioxidant power (FRAP) and total phenolic content but promoted the degradation of flavonoids. In contrast, the blends of ginger and turmeric substrate showed the lowest DPPH (5.23 ± 0.28 %), FRAP (54.46 ± 0.54 mM of Fe2+ /L), total phenolic content (5476.10 ± 36.80 mg GAE/100 mL) as compared with other samples. In addition, physicochemical analysis demonstrated that the fermentation time introduced to significant increase in mass of SCOBY in the kombucha. While the pH values of the samples decreased during the fermentation time, the acetic acid content increased. However, the turmeric substrate showed the lowest reading of acetic acid content in which is 0.45 ± 0.01 % as compared with other samples. In addition, the fermentation process promoted to the significant decrease in total soluble solids content (˚Brix). There was no significant difference (p > 0.05) between the pH value, and color change of ginger, turmeric and blends of ginger and turmeric kombucha, but the black tea kombucha promoted a lower pH value (2.80 ± 0.01) and Brix (8.1 ± 0.1), with lower color change (ΔE) (12.43 ± 0.23). When the color values were examined, it was found that the color change of black tea kombucha was significantly increase but become constant after 8 days of fermentation. Overall, ginger and turmeric were suitable to use as the additional ingredients in kombucha because both ginger and turmeric provide higher antioxidant activity and phenolic content as compared with the black tea kombucha