Effects of manufacturing conditions on the foaming properties of milk and sensory characteristics of foamed milk

The foaming properties of milk manufactured under different conditions were investigated using a Dynamic Foam Analyzer 100. The sensory characteristics of foamed milk were evaluated by descriptive analysis by means of a trained panel. Milk homogenized at 25 MPa had significantly smaller bubble size and higher foam stability than milk homogenized at 7 MPa. Foamed milk prepared from milk homogenized at 25 MPa had significantly higher sensory evaluation scores for 'fineness', 'smoothness', 'elasticity', and 'body', and a significantly lower score for 'meltability' compared to foamed milk prepared from milk homogenized at 7 MPa. Milk heated at 120 degrees C had a significantly smaller bubble size than milk heated at 140 degrees C. Foamed milk prepared from milk heated at 120 degrees C had a significantly higher score for 'sweetness' than did foamed milk prepared from milk heated at 140 degrees C. In addition, milk heated using infusion-type pasteurizer had a significantly smaller bubble size compered to milk heated using a plate-type pasteurizer. Foamed milk prepared from milk heated using an infusion-type pasteurizer had significantly higher scores for 'fineness' and 'smoothness', and a significantly lower score for 'cooked-flavor' compared to foamed milk prepared from milk heated using a plate-type pasteurizer.