some floating free, some embedded in the membranes of the fat globules Pasteurization (p 22) greatly reduces this vitality; in fact residual enzyme activity is taken as a sign that the heat treatment was insufficient Pasteurized milk contains very few living cells or active enzyme molecules, so it is more predictably free of bacteria that could cause food poisoning, and more stable; it develops off-flavors more slowly than raw milk But the dynamism of raw milk is prized in traditional cheese making, where it contributes to the ripening process and deepens flavor The making of milk Cells in the cow’s mammary gland synthesize the components of milk, including proteins and globules of milk fat, and release them into many thousands of small compartments that drain toward the teat The fat globules pass through the cells’ outer membranes, and carry parts of the cell membrane on their surface Milk owes its milky opalescence to microscopic fat globules and protein bundles, which are just large enough to deflect light rays as they pass through the liquid Dissolved salts and milk sugar, vitamins, other proteins, and traces of many other compounds also swim in the water that accounts for the bulk of the fluid The sugar, fat, and proteins are by far the most important components, and we’ll look at them in detail in a moment First a few words about the remaining components Milk is slightly acidic, with a pH between 6.5 and 6.7, and both acidity and salt concentrations strongly affect the behavior of the proteins, as we’ll see The fat globules carry colorless vitamin A and its yellow- ... proteins and globules of milk fat, and release them into many thousands of small compartments that drain toward the teat The fat globules pass through the cells’ outer membranes, and carry parts of the. .. salts and milk sugar, vitamins, other proteins, and traces of many other compounds also swim in the water that accounts for the bulk of the fluid The sugar, fat, and proteins are by far the most important components, and we’ll... far the most important components, and we’ll look at them in detail in a moment First a few words about the remaining components Milk is slightly acidic, with a pH between 6.5 and 6.7, and both acidity and salt concentrations strongly affect the behavior of