Raw Milk is considered as a tremendous medium for contagious growth of bacteria’s and other pathogens which soon get
accelerate when stored at ambient temperature. Pakistan is at 3rd place in worldwide milk production. Here about 41.6 million
ton of milk is being produced annually from which only 5% get processed and pasteurized hardly and remaining proportion of
milk is handled by milk man under non-hygienic conditions which causes diseases. Dairy processing is a rapid growing
business but high operational cost is a serious problem. The solar energy in combination with vacuum tube collector having
200 litres capacity and 2.088m² collector area is an efficient way of pasteurizing the milk. Steam is used to pasteurize the milk
stored in stainless steel tanks. Milk is heated up-to 63°C temperature in 30 minutes, then cooled down to 30°C through heat
exchanger by using natural tap water. Furthermore, milk is cooled down to 4°C in the chiller within 90 minutes which is
powered by 2kW Photovoltaic system. Rotary compressor was used in the chiller which reduces shunt load. Torque load is
zero by applying invertor technology in chiller. Efficiency of the unit was achieved up-to 69%. The payback period of this unit
is 3.8years and processing cost occur 1.8 PKR per litre. This research study is conducted to prolong the shelf life of milk and
results as the most excellent and economical way of preserving milk through this solar energy resource technique.
Muhammad Usama Yaseen, Muhammad Ashraf , Anjum Munir. (2019) DEVELOPMENT AND PERFORMANCE EVALUTION OF SOLAR ASSISTED MILK PASTEURIZER BY USING VACUUM TUBE COLLECTOR, , Volume 56, Issue 3.
