2023-05-14 01:07:18
The Mesopotamian civilization developed the first agricultural and livestock systems, invented the wheel and writing, among many other innovations. It is precisely in Sumerian documents that the first reference to milk as a source of food appears.
However, to find the origin of milk we have to go back some 310 million years, when the ancestors of mammals, the synapsids, developed a secretion that served to moisten the eggs they incubated. Over time, that liquid increased the concentrations of casein and calcium.
Consistency similar to toothpaste
Currently, the milk of mammals is made up mainly of water, carbohydrates, proteins and fats, the proportions varying depending on the species. In addition, there is enormous variability in terms of milk produced.
Thus, for example, a shrew does not produce one milliliter a week, while a blue whale can produce 220 kilograms of milk daily, an energy contribution capable of feeding two hundred people throughout a year.
Whale milk, like that of other marine mammals, has a high concentration of fat and protein, and a low proportion of carbohydrates, which makes its consistency resemble that of toothpaste.
It is precisely thanks to this idiosyncrasy that allows the milk to reach the mouth of the calf – the calf of the whale – and not to be diluted in the water around the calf, since whales do not have lips.
The responsible is the casein
Milk is made up of approximately 88% water and a mixture of solid particles, the main protein being casein, which helps our body absorb calcium. This protein groups with another component of milk -calcium phosphate- to form spherical structures known as micelles, which are one micrometer wide.
These micelles, along with some fat corpuscles, form a colloidal solution that gives milk most of its physical characteristics, as well as its characteristic white color.
However, the first breast milk, also known as colostrum, is yellow-orange in color, due to its composition in beta-carotene, a natural pigment with antioxidant action. This milk is thick, sticky and is fully adapted to the needs of the newborn, its main function being immunological.
Milk can also be blue
One of the elements of the saga created by George Lucas is blue milk, also known as bantha milk, fictitious creatures that are used as pack or transport animals on the planet of Tatooine. This milk, in addition to its coloration, is characterized by its thickness and sweet taste.
A few years ago the international press covered the appearance of blue milk in a town near Turin. Apparently the tonality of this milk was not due to the Star Wars creatures, but was caused by the contamination of a bacterium: Pseudomonsa fluorescens.
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