Enzyme eliminates fouling in UHT milk production

REIGATE, UK- Milk undergoes several heat treatments to kill pathogenic bacteria, but heat is also the cause of fouling when milk proteins, sugars and minerals start to caramelise in the UHT unit. The build-up of pressure in the system reduces heat transfer, necessitating frequent production shutdowns for cleaning.  

DuPont has found a way to remove fouling in ultra-high temperature (UHT) milk products by using a solution containing an enzyme called the FoodPro? Cleanline. To work, the enzyme is added to the milk before UHT processing. It is activated during heat treatment and then becomes just another protein among the milk proteins. A small dose of the product modifies the phospholipids naturally present in milk prior to heat treatment, limiting the ability of milk components to settle on the heat exchanger.

In trials where FoodPro was used, a UHT processing can run for up to more than twice as long between cleaning cycles, said Aurélie Gammelin global product manager for dairy enzymes. “Because UHT dairy manufacturers use less chemicals, water and energy for cleaning, there is a positive knock-on effect for their environmental profile. The level of organic material in wastewater is similarly reduced,” she said.

Using the product will increase a milk producer’s capacity and reduce costs, and will also optimise processing uptime without any effect on the product. At the same time, a milk manufacturer will be using less cleaning chemicals damaging to the environment. To measure just how much, DuPont designed a calculator tool to show the cost savings and annual profit gain, as well as the estimated savings in water and CO_2.

Due to the reduced tendency of milk components to caramelise on the heat exchanger, the final UHT product has no burnt off-taste. Emulsion stability is also improved.

For more information, contact Pernille Holst Moulvad, marketing manager, DuPont Industrial Biosciences, Food Enzymes, +45 8943 5575 or pernille.holst.moulvad@dupont.com.