Steaming

Japanese tea steaming applies pressurized steam at approximately 100 degrees Celsius for 15-120 seconds, depending on the desired style. The moist heat instantaneously denatures oxidizing enzymes without the Maillard browning that occurs in Chinese pan-firing. This preservation of chlorophyll, amino acids, and vitamin C gives Japanese green tea its characteristic bright jade color and umami-forward, ocean-breeze freshness. Steaming duration defines three major sencha styles: asamushi (light, 15-30 seconds) produces clear, delicate liquor with defined needle shape; chumushi (standard, 30-60 seconds) balances clarity and body; fukamushi (deep, 60-120 seconds) creates an opaque, intensely green, full-bodied cup. The steaming machine (mushiki) is the critical piece of equipment in any Japanese tea factory, and its calibration — steam pressure, leaf throughput rate, and conveyor speed — requires years of expertise to master.