Chlorophyllases (EC 3.1.1.14) are enzymes that break down chlorophyll into phytol and chlorophyllide, driving the loss of green colour in harvested produce, processed vegetables, and tea. In green tea manufacture they generate pheophorbide, a compound linked to skin sensitivity. Food technologists control blanching time and temperature and other processing conditions to manage chlorophyllase activity, preserving the fresh green appearance consumers expect in frozen peas, canned beans, and similar products. Because these enzymes act quickly after harvest, rapid cooling and prompt processing are the first defences against unwanted colour degradation.