*4.1.1.1 Open sun drying*

Here, food products are placed right under the sun, below solar radiation to get rid of their moisture properties. The difference in density in the air from the atmosphere allows for air movement. In other words, to get a product dried, they are usually spread in a large area under solar radiation. It is usually time-consuming till it is dry to a required level. All that is needed is a large surface ground done with concrete or a suitable soil area with products laid on them between ten to thirty days depending on a favorable weather situation. This form of drying technique consumes a lengthy time of sun subjection which can sometimes bring down the nutrition level of the products, like sapping off their vitamins.

Open solar drying is a good choice for food drying but comes with a lot of problems such as reduced product quality, adverse effects of rain, moist, wind, animal consumption, and dust [24]. The use of industrial drying comes in as another option which is very expensive. It would need a lot of fossil fuel which will result in air pollution. Nonetheless, the spread and adoption of solar energy is likely to take prominence in the coming years and is without negative environmental effective factors [24].
