Achieving Food Sterility With Steam Infusion UHT Treatment

By Gorm Kjaerulff, Product Category Manager, UHT & ESL, Dairy, SPX Flow Technology

UHT, or Ultra-High Temperature, treatment uses high temperature for a short time to kill micro-organisms in a food or beverage product. It is widely used in the dairy industry where products can easily lose nutritional value, flavor, and appearance as micro-organisms multiply. These organisms thrive at certain temperatures, but if they are not present in a product, it can be stored for many months without the need for refrigeration. This state is known as “commercial sterility.”

UHT processes are designed to achieve commercial sterility. The procedures use heat to treat the product killing viable micro-organisms. This aseptic processing also requires equipment and packaging to be sterile, achieved with chemical, or other sterilization treatments.

There are many technologies available for the UHT treatment of products. Direct heating methods, such as steam injection or steam infusion, mix the heating steam with the product. Indirect heating methods, such as plate or tubular heat exchangers, keep the product and heating medium separate with a stainless steel barrier between them.