Aeration of low fat dairy emulsions: Effects of saturated-unsaturated triglycerides

Three dairy emulsions containing 10 wt% anhydrous milk fat (AMF), alone or in mixture with its low or high melting temperature fraction (olein- or stearin-rich fraction, respectively), were aged at 4 degrees C for 24 h and then submitted to a whipping test at this temperature. We observed that the AMF/olein emulsion presented less crystalline fat content, and a higher ability for air incorporation than the other two emulsions. In addition, air bubbles formed in the AMF/olein-rich emulsion presented a more uniform size distribution, a smaller proportion of bubbles higher than 50 pm, and they appeared to be coated with a thicker layer of fat droplets. These results indicated that foam-structure forming properties in reduced milk fat emulsions can be enhanced by lowering the proportion of saturated triglycerides. (c) 2007 Elsevier Ltd. All rights reserved.