The mango harvest season has duration of 3 – 4 months. During this season apart from selling mango for fresh consumption, a major portion of the harvest is converted into pulp to cater the need of juice making and other value addition purpose. The pulp has a shelf life of more than a year even without air-conditioning. Mango leather/jelly is one of a delicacy product having a good market demand. Presently this product is prepared by drying the pulp at 60 Deg C.
By using solar heated air at 60 Deg C , the firewood consumption for the Drier could be reduced. The solar heating unit saves fuel consumption around 60 to 80%.
The system doesn’t need big maintance except cleaning of glass which takes two hours of two workers for every week.
The switching over from solar heating to conventional heating during rainy day is very easy.
In nutshell the working of the system is satisfactory and it saves fuel consumption.
A 55m2 area solar collector generated sufficient hot air to dehydrate in 8 hours around 120 kg of mango concentrate. This unit has a back up heating with bio- mass fuel. This project will handle a minimum of 30 tones of fruit concentrate per annum and create employment of 1500 man-days per year. These kinds of unit could be replicated throughout the country mainly on the mango and other fruits growing areas.
M/s. Eswari Srinivasa Food Products , Andhra Pradesh