|Thomas, Andrew - Aj|
Submitted to: Annual Meeting of the Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 6/14/2000
Publication Date: N/A
Technical Abstract: Ice cream is a complex food foam system consisting of air, fat, ice, and serum phases. Although hard-pack ice creams have been studied to relate composition and processing conditions to rheological properties, very little data is available for soft-serve ice creams. The purpose of this work was to study the rheological properties of a commercial soft-serve ice cream and to compare the results to those obtained for a low-fat ice cream prepared using Fantesk**TM. Fantesk describes a class of stable starch-lipid composites formed by steam jet cooking of starch and lipid phases. In this case, waxy maize starch and butter were used, and the butter content was selected to give 1-2 wt% butter in the ice cream mix. Measurements were conducted on a Rheometrics ARES controlled-strain rheometer with parallel plates. The rheometer was equipped with an air convection oven and a mechanical chiller to allow temperature control within +/ 0.1 deg C. The starch content of the Fantesk-based soft-serve ice cream increased its freezing point, but measurements on both ice creams at their serving temperatures were similar. Strain sweep experiments showed that both formulations had similar moduli in the linear viscoelastic regime, although the linear region for the Fantesk formulation extended to much higher strains. Dynamic frequency sweeps were also similar, with G' > G" over the entire frequency range for both samples. Both formulations also showed an overshoot on startup of steady shear. The effects of mix composition, overrun and temperature were also studied. These results show that a low-fat soft-serve ice cream can be formulated with Fantesk that maintains similar mechanical properties to a commercial soft-serve ice cream.