Milk is essential in espresso, so what are the milk processing procedures?

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When coffee is mixed with milk, take cappuccino, for example, a whole cup may be 2/3 of milk, you have to pay as much attention to the quality of coffee and milk.

The author uses several different types of milk, but the differences between soy milk vs almond milk and full-fat vs low fat are not discussed here. Although these are also important, this paper focuses on the treatment procedures of milk: raw milk, heating sterilization, high temperature treatment, etc. Let's learn about the differences and how they will present the flavor of cappuccino.

The main treatment of milk

Here we need to discuss some technical issues first.

The latest fresh milk that is least processed and available to people is "raw milk", which is unpasteurized and homogenized milk. A more detailed explanation is as follows:

Sterilization: raw milk is not quickly heated and cooled to kill bacteria.

Homogenization: the fat molecules of raw milk are not broken down to prevent the milk from forming a cream layer on the surface.

Because raw milk has not been sterilized at high temperature, it has always been controversial. The US Food and Drug Administration has strongly warned consumers not to drink raw milk. By contrast, many French cheeses are made from raw milk, while the British Food Standards Agency believes that as long as raw milk is properly controlled, it is suitable for non-sensitive groups to drink. Critics of raw milk point out that drinking raw milk can cause food poisoning, while supporters of raw milk say raw milk is tastier and healthier (even if health issues are not supported by research).

You can also buy milk that is pasteurized but not homogenized, and, less commonly, homogenized milk that is not pasteurized. However, generally available milk is pasteurized and homogenized.

There are many forms of high temperature sterilization, of which the two most common are "high temperature short time sterilization HTST" and "ultra high temperature instant sterilization UHT". According to the International Dairy Association, HTST milk will be heated at 70-75 oC for 15 seconds and still need to be refrigerated; ultra-high temperature instant sterilization UHT milk will be heated at 120-130 oC for 2 seconds.

(readers add that there are two other treatments: low temperature long time sterilization (LTLT): 62-65 oC, heated for 30 minutes.

Ultra-high temperature sterilization (UHT-sterilization) can also be called preserved milk: 135-150 oC, heated for 2-5 seconds. )

High temperature sterilization but not homogenization

Remember that there are many ways to sterilize milk at high temperature. Milk heated by 63oC for 15 seconds is used here. Drink from the cold, you can drink a very sweet but thinner taste; steaming will increase the slightly round taste, while the sweetness can remain the same as when it is cold. However, when a cappuccino is made, it will enhance the bitterness of the coffee and give the whole feeling of over-caramelization.

So the author conducted a second experiment: using beans with roasted degree of hand-brewed coffee to boil and concentrate, and try to drink only concentrated and add two cups of milk flavor. When drinking espresso, it tastes sour; the addition of milk amplifies the fruit flavor and increases the overall sweetness of the coffee. For the author, this milk is perfect for making fruit-flavored cappuccinos (shallow baked beans).

UHT ultra-high temperature method

This kind of milk has a long and creamy finish, but it is so sweet that it tastes like a can. After steaming, the surface is smooth and creamy, but there are no foam. After making cappuccino, there is still no milk foam, and the flavor becomes bitter and insipid.