Whipped Cream Structure Measured by Quantitative Stereology

¹ Department of Food Science, University of Guelph, Guelph, ON, Canada N1G 2W1

Whipping cream, with 35% milk fat, was high temperature, short time pasteurized and ultra-high temperature sterilized, with and without the addition of stabilizer, to study the effect of these processing conditions on the stability of foam structure. Processed creams were whipped to maximum overrun using a double beater system and were immediately prepared for low temperature scanning electron microscopy. Duplicate foams were refrigerated for 24 h before processing for low temperature scanning electron microscopy. Air bubble sizes, lamella lengths, and volume fraction of air in the foams were measured using quantitative stereology. A significant increase was noted for bubble size and lamella length in aged foams. Comparison between aged foams showed a significant difference caused by heat treatment. Foams prepared from unstabilized or stabilized pasteurized creams had significantly larger bubbles than those prepared from comparable sterilized creams. Therefore, differences between foams whipped from stabilized creams were primarily due to effect of heat treatment.

Key Words: whipping cream • heat treatment • stabilizer • stereology

Submitted on November 4, 1998
Accepted on April 5, 1999