The following are the processes involved in the Food Processing Industry that require heat energy to generate hot air, steam and hot thermic oil where we can use concentrated solar power technologies for meeting demand of heat energy:
- Pasteurization – solar steam heating
- Drying of vegetables / fruits – solar hot air
- Frying of edible items – hot thermic oil
- Pasteurization – solar steam
There are several applications that require thermal energy in the food processing industry. A few of them are listed below
Processing Fruits/Water Contained Vegetables (Pulp/ Ketchup and so on)
The following process flow diagram depicts the typical processes that take place for packed pulp products:
The pasteurization of pulps takes place with the help of steam heating. Evaporation takes place in the vacuum pans so as to maintain the aroma of the fruit/vegetable. The pulp / ketchup is stirred inside steam jacketed vacuum pan. Generally the steam is required in the range of 5-7 bar for above processes. This steam can be easily delivered using solar thermal systems.
Drying Various Fruits/ Vegetables for long-term preservation
Different fruits and vegetables are dried for different applications mainly to remove the water content in them. This process increases the shelf life of the product. Many times vegetables are dried to convert them into the powder form. The process of drying can be done by various methods. Passing hot air over these products is the most popular method. Drying of fruits/vegetables with the help of solar heat is the oldest method of all. With modern solar hot air generation systems, temperatures of 110-200°C can be achieved, which can boost the rate of drying to a great extent.
Frying various edible items for packed food
The Packed food is generally fried using edible oils where mostly wood fire is used for heat. The recent trend in this industry is frying using thermic oil system. Frying requires thermic oil at temperatures above 250°C. The SolwedISH solar system can be used to provide thermic oil up to 500°C for these applications.
Pasteurization of products for germ killing
Many dairy products or other easily perishable products are pasteurized by heating and cooling them immediately one after another. This helps to give the germs a thermal shock and increase the life of the product. The heating of the product is generally carried out using steam of around 6 bar. This steam can be generated with the help of solar system.