Optimization of Inorganic Ceramic Membrane Filtration Process for Tea Enzymes

Abstract

In order to enhance the clarity of tea enzymes while maximizing the preservation of their functional components during the clarification process, this experiment utilized tea enzymes derived from summer and autumn tea fermentation as the primary material. Through both single-factor and response surface experiments, the effects of inorganic ceramic membrane pore size, transmembrane power, transmembrane pressure, and transmembrane temperature on the content of functional components, membrane flux, transmittance, and soluble solids content of the enzyme solution after membrane filtration were examined. The objective was to determine the optimal conditions for ceramic membrane filtration of tea enzymes. The results showed that, the ideal conditions for ceramic membrane filtration of tea enzymes were as follows: Membrane pore size of 400 nm, transmembrane power of 47 Hz, transmembrane pressure of 0.28±0.02 MPa, and transmembrane temperature of 15±2 ℃. Under these conditions, the retention rates of tea polyphenols, theanine, zinc, selenium, and soluble solids content in tea enzymes were 95.28%, 82.91%, 90.48%, 91.67%, and 84.46% respectively. The transmittance reached 85.10%±0.12% with 2.5-fold improvement compared to before membrane filtration. Additionally, the membrane flux achieved 123.25±2.68 m3/(m2·h). These optimal conditions not only maximized the retention of functional components in tea enzymes, but also ensured their transparency and uniformity. Therefore, employing these conditions for the filtration and clarification of tea enzymes was a viable approach.

Keywords

• tea enzyme
• inorganic ceramic membrane
• filtration
• process optimization
• tea polyphenols
• theanine
• retention rate