IMPROVEMENT OF EQUIPMENT FOR DRYING FRUIT AND VEGETABLE RAW MATERIALS BASED ON AUTOMATION MEANS

Abstract

It is noted that fruit and vegetable raw materials contain a number of nutritional components that are beneficial to human health: vitamins, minerals, carbohydrates, which support health, increase immunity and prevent diseases. However, vegetables and fruits cannot be stored for a long time in natural conditions, which requires extending the shelf life of raw materials using various preservation methods, including drying and freezing. Attention is focused on the fact that drying processes should reduce drying time and minimize energy costs while maintaining high product quality. Therefore, the use of automated control technologies will make it possible to improve the operation of equipment for drying plant raw materials, namely, maintaining the desired quality and reducing defective products. It is proposed to predict potentially expected changes in pressure, temperature and humidity during the primary and secondary stages of freeze-drying, which have different drying mechanisms and require careful monitoring and control to ensure the quality of the obtained dried raw materials using control and measuring equipment, which will help avoid damaged raw materials, destruction of the internal structure, as well as deterioration of many product characteristics, such as texture, volume, shape and color. It is considered advisable to reduce changes in the quality of fruit and vegetable raw materials to use combined drying methods, namely, combining freeze-drying with microwave, infrared or convective drying methods. The process of drying bananas by various methods was studied: convective and microwave methods, as well as combined drying methods, namely, sublimation-convective and sublimation-microwave drying methods. The effect of these drying methods on the physical parameters of the raw material (color, shape, texture) was compared. The results show that in the process of drying bananas it is advisable to use the convective drying method, sublimation-convective and sublimation-microwave drying methods, because the obtained raw material samples have the desired color, shape and texture. However, during microwave drying, banana samples were obtained that do not meet the specified quality indicators, because they have a slightly brownish color, a structure that is somewhat fragile, not elastic enough and slightly deforms when bent. The results of the study were interpreted.