**2.5 Comparison of different drying methods**

There are several different methods for drying materials, including air drying, freeze-drying, spray drying, and vacuum drying. Each method has its advantages and disadvantages, and the choice of drying method depends on the nature of the material being dried and the desired characteristics of the final product [25–29].

1.*Air drying*: Air drying is a simple and low-cost method of drying that involves exposing the material to air and allowing it to dry naturally. This method is suitable for drying materials that are not sensitive to heat and that do not require rapid drying. However, air drying can be slow and may not be suitable for materials that require precise control of temperature and humidity.


In summary, each drying method has its advantages and disadvantages, and the choice of method depends on the nature of the material being dried and the desired characteristics of the final product. Air drying is a simple and low-cost method, freezedrying is suitable for preserving biological activity, spray drying is suitable for producing dry powders with good solubility and dispersibility, and vacuum drying is suitable for heat-sensitive materials that require precise control of temperature and humidity.
