Nathanon Trachoo

pp. 791 - 797

Abstract

Consumer needs for low caloric and reduced fat foods has increased in Thailand. Cholesterol in milk
fat has been a drawback for milk products. Reduction of fat results in undesirable effects in some products.
To reduce fat in yogurt, total solid is lowered to 9-10%. This adversely affects physical and sensory properties of yogurt. Syneresis, weak body, lack of flavor and poor texture and mouthfeel are common defects of
nonfat and lowfat yogurt. Our previous study has shown that yogurt made from milk with high milk fat
globule membrane (FGM) had less whey separation. The objective of this study was to investigate the association of FGM on protein matrix in dairy gels using confocal microscopy. Sweet buttermilk contains a large
amount of FGM. A model system was used by addition of glucono-δ-lactone into yogurt mixes. When directly
acidified, membrane-like materials were observed under the microscope. They functioned as bridges linking
protein matrices together resulting in a more defined protein network. This suggested that FGM has a
potential to improve textural properties of yogurt.