Whipped cream structure measured by quantitative stereology

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