Dry heat treatment of skim milk powder greatly improves the heat stability of recombined evaporated milk emulsions
(19-02-2021) UGent researchers succeed in avoiding heat coagulation when sterilising concentrated milk.
Reason
Recombined evaporated milk (REM) is an ultra-high heat treated product that is made typically by homogenization of an aqueous mixture of skim milk powder and fat. One of the biggest challenges during REM manufacturing is the heat-induced coagulation during the heat treatment, which largely depends on the heat stability of the skim milk powder. The visible coagulation is generally accompanied with fat separation or brown discoloration which adversely affects the product quality and production equipment.
Research
Skim milk powder contains proteins and sugars which can react with each other to form glycosylated proteins. This process is promoted by dry-heating the skim milk powder under controlled conditions, and may result in a powder with improved functional properties.
Results
Pre-treating skim milk powder with a dry-heating procedure was found to improve the heat stability of REM greatly in this study. The applied conditions in this study demonstrated the possibility of preparing REM which could withstand at least 30 min of sterilisation at 120℃ without significant increases in the particle size or viscosity.