Change in cell membrane permeability in tea flush on storage after plucking and its effect on fermentation in tea manufacture

Abstract

AbstractThe permeability of cell membranes in tea flush increased on storage after plucking when the flush was allowed to desiccate as in orthodox tea manufacture. The increase in membrane permeability was roughly proportional to the degree of desiccation until the flush approached about 55% moisture content at which the permeability is a maximum.At room temperature (about 22°) there was no appreciable change in membrane permeability in non‐withering flush until after about 30 hours of storage. However, chilling temperatures (4° and 10°) markedly increased membrane permeability even in the absence of any desiccation, and killing temperatures (−15° and 40°) were even more effective.The importance of increase in cell membrane permeability to tea manufacture is discussed in relation to the ease with which the catechol oxidase can be mixed with the catechins in the cells, a process which is essential for the initiation of tea fermentation.