The US infant formula market is estimated at over
$3.5 billion, of which 75% are dairy-based formulas.
Dried dairy powders pose a significant food safety risk,
with Cronobacter sakazakii and Salmonella spp. being
pathogens of particular concern. Radio frequency
dielectric heating (RFDH) can provide rapid, uniform
heat treatment of dry powders; thus, it potentially
may be used as a postprocess lethality treatment for
nonfat dry milk (NDM) or powdered infant formula.
Because RFDH is a heat treatment, the functionality
of the NDM may be altered and should be evaluated.
High heat- and low heat-NDM were RFDH processed
at temperatures ranging from 75 to 90°C for 5 to 125
min. Products were then assessed for whey protein
nitrogen index (WPNI), solubility, and color. In low
heat-NDM, RFDH decreased WPNI and solubility
if the process was done at ≥80°C; however, in high
heat-NDM, RFDH had a greater effect on solubility
than WPNI and some color properties were altered.
Further investigation of RFDH is merited to validate
its application as a pathogen control process for NDM
across processing parameters that result in acceptable
functional properties for infant formula and other food
products containing NDM.