Red Yeast Rice Production

Production

Red yeast rice is produced by cultivating Monascus purpureus on polished rice. The rice is first soaked in water until the grains are fully saturated. The raw soaked rice can then either be directly inoculated, or steamed for the purpose of sterilizing and cooking the grains prior to inoculation. Inoculation is done by mixing M. purpureus spores or powdered red yeast rice together with the processed rice. The mix is then incubated in an environment around room temperature for 3–6 days. During this period of time, the rice should be fully cultured with M. purpureus, with each rice grain turning bright red in its core and reddish purple on the outside.

The fully cultured rice is then either sold as the dried grain, or cooked and pasteurized to be sold as a wet paste, or dried and pulverized to be sold as a fine powder. China is the world's largest producer of red yeast rice.

Due to the low cost of chemical dyes, some producers of red yeast rice have tried to adulterate their products with red dye #2 Sudan Red G [1](in Chinese).