The basic ingredient for the preparation of butter is the creamor milk cream, i.e. the fat component of the milk that is obtained through two main methods: the centrifugationquite quick process, and theoutcrop. The latter procedure is slower, which lasts about 15-20 hours and during this wait the bacteria naturally present in milk (the so -called Lablactic bacteria) metabolize some molecules leading to the formation of acid compounds. For this reason, the cream obtained for outcrop is known as sour creamwhile the centrifugation one has a more sweet taste because the much faster process that does not give time to bacteria to perform any type of fermentation. Once the cream is recovered, it is subjected to a process called zanellingan enduric processing that breaks the membranes of fat blood cells, allowing them to join, coagulate and separate from the dairy, the waste liquid. The butter is then washed, stunned and modeled in the classic loaves, taking on its creamy and spreadable consistency. Butter like milk is also aemulsionbut this time the fat part is predominant compared to the aqueous phase.
The procedure for producing the cream from the cream
The cream is first subject to various thermal treatments, which include one pasteurization To break down a large part of the microbial charge (especially if it is a cream deriving from outcrop) and to deactivate some enzymes that could cause the butter to raise; A cooling phase then takes place (normally below 7 ° C, but depends on the type of process) to obtain the crystallization of fats: this phase is essential to give the final butter structure, make it less oily And more spreadable.
The trial process provides for a process called zanelling. The term derives from the containers within which this phase has historically occurred, the zancules: they were wooden containers with a cylindrical shape inside which the cream was inserted and below beaten with a plunger who was raised and lowered by hand inside the cylinder. Modern and mechanical devices are used on an industrial level, but always called zancules.
In normal conditions, the fat It is dispersed in the aqueous phase in tiny droplets protected by a thin layer of protein e phospholipidswhich prevents them from aggregating. However, the mechanical energy of the fool break these protective membranesallowing the fat blood cells to join together, through a process known with the name of coalence.
As fat globules aggregate, they separate from water and residual cream proteins. This leads to the formation of two distinct phases:
- There solid partcomposed of fat blood cells that come together more and more to form one compact and smooth mass (which I will then give life to the butter).
- There liquid partcall buttermilkwhich will be drained and mainly contains water, proteins and a small amount of residual fat.
There lipid phase It is now ready for the transformation into butter. The consistency is still too grainy: at this point the butter is first washed with cold water to eliminate the residues of lacticello, then it is again stored and then compacted in the classic loaves.
Fun fact: butter is an emulsion like milk, but on the contrary
From a chemical point of view, the butter is mainly made up of fatlike saturated fatty acids and cholesterolwhich represent about 80% of the total composition. The remaining part consists of water, proteins, carbohydrates (mainly lactose), vitamins (such as vitamin A and vitamin E) and minerals (for example phosphorus, sodium and calcium).
Note how the presence of both fat and water presumes the fact that the butter, exactly like milk, is aemulsionthat is, a stable system in which aqueous part and fat part are mixed. However, there is a substantial difference: while milk is aOil emulsion in water (Or/a), which means that we have tiny fat droplets dispersed in a predominantly watery environment; In the butter, on the other hand, the situation overturns and we have awater emulsion in oil (A/O) where the droplets of water are dispersed in a lipid matrix, derived from the coalence of fat globules that joined during the zangulating to form a compact and greasy structure typical of butter.
