High pressure processing whips up thicker ice cream
Writing in the International Dairy Journal, scientists from University College Cork, Nizo Food Research and the University of Guelph sought to assess the effects of high pressure (HP) treatment on ice cream and discover the mechanisms responsible for the changes.
HP processing is increasingly popular as a food preservation and sterilization method but has only recently attracted the attention of scientists as a tool to improve the functionality of milk proteins.
In the new study, published online ahead of print, scientists said their research indicates that HP treatment could have several important benefits for ice cream manufacturers.
These include the improvement of reduced-fat ice cream and the possibility of making products without the additives that are normally included to prevent ice crystallization.
HP treatment may also allow ice cream manufacturers to cut raw material costs by reducing the protein content without compromising texture or mouthfeel.
These benefits are a result of the increased viscosity and higher resistance to melting induced by the HP processing.
Seeking to explain the mechanisms behind these effects, the scientists said: “Transmission electron micrographs showed the presence of a network of micellar fragments, arising from HP-induced disruption, in the HP-treated mix and ice cream prepared there from.
“The network of micellar fragments is believed to be responsible for the increased viscosity and reduced melting, and is hypothesized to occur as a result of calcium-induced aggregation of caseins on decompression.”
Study author Thom Huppertz from Nizo told this publication that HP processing is ready for use by ice cream manufacturers, and that the necessary equipment is available on a commercial scale.
But from a research point of view Huppertz called for further studies on HP-treated ice cream mix to better establish sensory properties and shelf stability.
The Irish government agency Enterprise Ireland provided funding for the research.
Source: International Dairy Journal
(2010), doi: 10.1016/j.idairyj.2010.12.005
Effects of high pressure treatment of mix on ice cream manufacture
Authors: Huppertz, T., Smiddy, M.A., Goff, H.D., Kelly, A.L.