many of its fat globules rise and form a fatrich layer at the top of the container This phenomenon is called creaming, and for millennia it was the natural first step toward obtaining fat-enriched cream and butter from milk In the 19th century, centrifuges were developed to concentrate the fat globules more rapidly and thoroughly, and homogenization was invented to prevent whole milk from separating in this way (p 23) The globules rise because their fat is lighter than water, but they rise much faster than their buoyancy alone can account for It turns out that a number of minor milk proteins attach themselves loosely to the fat globules and knit together clusters of about a million globules that have a stronger lift than single globules do Heat denatures these proteins and prevents the globule clustering, so that the fat globules in unhomogenized but pasteurized milk rise more slowly into a shallower, less distinct layer Because of their small globules and low clustering activity, the milks of goats, sheep, and water buffalo are very slow to separate Milk Fat Globules Tolerate Heat… Interactions between fat globules and milk proteins are also responsible for the remarkable tolerance of milk and cream to heat Milk and cream can be boiled and reduced for hours, until they’re nearly dry, without breaching the globule membranes enough to release their fat The globule membranes are robust to begin with, and it turns out that heating unfolds many of the milk proteins and makes them more prone to stick to the globule surface and to each other — so the globule armor actually gets progressively thicker as heating proceeds Without this stability to heat, it would be impossible to make many cream-enriched sauces and reduced-milk sauces and sweets …But Are Sensitive to Cold Freezing is a ... release their fat The globule membranes are robust to begin with, and it turns out that heating unfolds many of the milk proteins and makes them more prone to stick to the globule surface and to each other... proteins are also responsible for the remarkable tolerance of milk and cream to heat Milk and cream can be boiled and reduced for hours, until they’re nearly dry, without breaching the globule membranes.. .and low clustering activity, the milks of goats, sheep, and water buffalo are very slow to separate Milk Fat Globules Tolerate Heat… Interactions between fat globules and milk proteins