Chili peppers are an important vegetable and condiment in daily life and are widely used in Henan, Sichuan, Gansu, and Hunan. Henan primarily cultivates the Chaotian pepper, Xinjiang primarily grows the large chili pepper, Gansu primarily grows the Rose Red variety of the large chili pepper, Inner Mongolia primarily grows the Jinta Red and Yidu Red varieties of the large chili pepper, Shandong primarily grows the Yidu Red and Wangdu Red varieties of the large chili pepper, Hebei primarily grows the Chaotian pepper, Yunnan primarily grows the Chaotian pepper, Shanxi, Sichuan, and Guizhou also grow Chaotian pepper, and Shaanxi grows the Linear pepper. However, large-scale chili pepper cultivation and traditional drying methods not only waste a lot of manpower and resources but are also significantly affected by weather, making them inadequate. The advent of chili pepper drying rooms has effectively solved this problem.
Chili drying rooms, also known as chili drying rooms, are a type of heat pump drying equipment widely used in chili pepper drying. They are constructed with insulating materials and utilize a heat pump unit as energy source, which circulates hot air within the room to achieve the desired drying effect.

Currently, there are two main drying methods for chili pepper dryer: direct drying and staged drying.

Direct drying: As the name suggests, direct drying involves drying directly in the chili pepper dryer. After setting the dryer's parameters, the chili peppers are placed on a rack tray and pushed into the drying room or stacked at the inlet of a mesh belt dryer, where they are fed by a mesh belt into the dryer for drying.

Stage drying: In this drying method, chili peppers with a moisture content of 75% to 85% are first dried to a moisture content of 50%, then piled and sweated before a second drying step. Pile sweating is a crucial step in the chili pepper drying process, significantly impacting chili quality, drying time, and yield. Chili peppers noticeably soften and swell during the drying process. Pile sweating primarily serves to condition the chili peppers, allowing the chili oils to penetrate the surface. This results in a uniform, rosy, and smooth color after drying, and helps balance the moisture content of the peppers. Without the second drying step, drying 1,000 kg of chili peppers at a hot air temperature of 40°C-60°C would take 63 hours. With the second drying step, the drying time is reduced to approximately 40 hours, and the yellowing and hulling are significantly reduced. After the second drying step, the resulting chili peppers are of exceptional quality.