forty-eight hours. Self-made perilla frutescens drink in Song Dynasty is best not to be stored for a long time, and it is best to drink it within 48 hours after it is obtained, because this Chinese medicine drink is easily influenced by the outside world, such as light and temperature, and long-term storage will lead to the loss of effective components or quality changes. Purple perilla drink in Song Dynasty is a traditional Chinese medicine drink, the main component of which is perilla leaf, which has the function of clearing away heat and toxic materials and is often used to relieve heatstroke in summer.