Production of low-tannin Hibiscus sabdariffa tea through D-optimal design optimization of the preparation conditions and the catalytic action of new tannase

Many tannase-based industrial applications are currently being developed to successfully break down tannins in teas and juices. However, so far, no study has demonstrated the potential application of tannase to reduce tannin levels in Hibiscus sabdariffa tea. The D-optimal design was utilized to predict the optimal conditions for maxi-mizing anthocyanins and decreasing tannin content in Hibiscus tea. Then, the effects of Penicillium commune tannase were evaluated by examining the physicochemical parameters and a-amylase inhibitory action of un-treated and treated Hibiscus tea, as well as quantifying catechin content changes using HPLC. Following treat-ment with tannase, the esterified catechins decreased by 8.91%, while the non-esterified catechins increased by 19.76%. Additionally, tannase significantly raised the total phenolic compounds by 8.6%. In contrast, the a-amylase inhibiting activity of Hibiscus tea decreased by & AP;28%. As a novel member of the tea family, tannase offers an excellent means of conditionally producing low-astringency Hibiscus tea.

Automated summary

Many tannase-based applications have been developed to break down tannins in teas and juices, but none have explored the potential application in reducing tannin levels in Hibiscus sabdariffa tea until now. This study used a D-optimal design to predict optimal conditions for maximizing anthocyanins and decreasing tannin content in Hibiscus tea. The effects of Penicillium commune tannase on physicochemical parameters, alpha-amylase inhibitory action, and catechin content changes were evaluated, showing a decrease in esterified catechins and an increase in non-esterified catechins after tannase treatment.