Comparison of Food, Fruit, and Vegetable Drying Methods

EKOTEC HEAT PUMP DRYING METHOD AND ITS DIFFERENCE FROM OTHER DRYING METHODS (1)

EKOTEC heat pump dryers recover latent and sensitive heat from the exhaust gas by condensing moisture from the drying air. In this way, the dried air's moisture is recovered and reheated with recovered heat, increasing energy efficiency. In contrast, in other traditional drying methods, this heat recovery would be lost to the atmosphere. This enables drying at low temperatures, low costs, and the ability to work in humid environmental conditions.

The EKOTEC heat pump dryer allows control of not only the air's moisture and temperature but also the heat recovery. Thus, a heat pump dryer can improve product quality while using less energy and reducing drying time. Any dryer that uses convection as its primary heat input mode can be equipped with a well-designed heat pump.

Heat pump drying technology is combined with other drying techniques to achieve better product quality, low energy consumption, high performance coefficient (COP), and high thermal efficiency.

Drying with a heat pump consumes only half or a third of the electricity used by condenser dryers. Compared to electrically heated convective dryers, heat pump dryers have the lowest operating costs.

OTHER DRYING METHODS

Solar and Sun Drying:

Sun drying refers to drying food directly under the sun. It is the oldest method of drying food, as it uses direct sunlight, natural air movement, ambient air temperature, and relative humidity. This process is slow and requires constant monitoring; foods must be covered at night to protect them from insects and cannot be used during rainy periods. As a result, it is a long drying process, and the conditions and parameters of the process cannot be controlled, leading to low-quality final products. However, it is the cheapest drying method and does not require special equipment or energy consumption, making it suitable for developing countries with favorable weather conditions for the process. The drying time depends on the product characteristics and drying conditions but typically lasts between 3 to 4 days.

Vacuum Drying:

Vacuum drying technologies are used to remove moisture at low drying temperatures when heat-sensitive food components need to be preserved. Vacuum drying is similar to freeze-drying, but in vacuum drying, the product does not freeze, and the vacuum is not as high as in freeze-drying. Heat transfer occurs through radiation and conduction in this process. The vacuum drying system consists of a vacuum chamber where the product is placed, a heat source, a device for generating and maintaining the vacuum, and components for collecting the evaporated water vapor from the food. Vacuum drying is rarely used for drying fish.

COMPARISON OF FOOD, FRUIT, AND VEGETABLE DRYING METHODS