The food industry over the years has witnessed great innovation and processes aimed at reducing losses and preserving food for long with hence reducing losses. Milk being so perishable requires adequate preservation and processing to keep it safe for human consumption.
In most milk processing plants, chilled raw milk is heated by passing it between heated stainless steel plates until it reaches 161°C. It’s then held at that temperature for at least 15 seconds before it’s quickly cooled back to its original temperature of 39°C to destroy disease-causing microorganisms and enzymes that contribute to food spoilage.
The conventional method of milk pasteurisation uses energy sources such as fossil fuel, firewood or electricity to generate steam or hot water for heating milk. However, GDC has come up with a unique and innovative way of milk pasteurisation that uses geothermal heat, a first for Africa.
Geothermal heat is indirectly used to heat cold fresh water in a coil tube that is then pumped to the milk pasteuriser, where milk is heated indirectly until the recommended temperature is attained. The Direct-Use demo site at Menengai has a milk pasteuriser with a capacity of 150 litres, and it uses a low-heat technique that takes about one hour to heat the milk until it reaches 70⁰C.
According to Japhet Towett, a Direct Use Engineer at GDC, a geothermal-heated milk pasteuriser has several benefits over the conventional method. “When compared to fossil fuel which is the main source of energy for commercial dairy processing units, thermal energy cost savings of more than 60% can be realized by using geothermal as a source of heat,” says Towett.
The use of geothermal heat in milk pasteurisation reduces energy costs and helps in preserving the environment by reducing carbon emissions. This innovation by GDC is a significant milestone in the food industry and has the potential to revolutionize the dairy sector in Africa.
The geothermal-heated milk pasteurizer in Menengai is a testament processing would deactivate unwanted microorganisms in wine. Spoilage enzymes are also inactivated during pasteurization. Today, pasteurization is used widely in the dairy industry and other food processing industries to achieve food preservation and food safety hence a game changer.