意式咖啡机蒸汽为什么越来越弱？蒸汽堵了怎么办？如何清洗咖啡机？

Understanding Coffee Machine Steam Power

As is well known, the steam from a coffee machine is primarily used for heating milk and creating milk foam. The strength of the steam determines how long it takes to froth milk—the stronger the steam, the faster the milk heats up and the shorter the frothing time, and vice versa. Recently, however, many friends have noticed that the steam intensity of their home coffee machines has been decreasing day by day, growing weaker every other day as their milk frothing time continues to increase. This is a rather serious problem, so they came to FrontStreet Coffee for consultation.

Some might think that even if frothing time increases, as long as the milk can be heated and foam can be created, it shouldn't be too problematic. However, milk foam that's frothed for too long actually becomes difficult to work with for latte art, because the initially created foam has already reached its limit and begins to break down gradually. This causes the foam to appear cloudy during latte art pouring, with unclear and blurry patterns. Therefore, we need to identify and solve this problem.

Why Does Steam Become Weaker?

If you don't hear any steam leaking from your coffee machine when it's not in use, then nine times out of ten, the problem lies with the steam wand's nozzle. The front end of a steam wand nozzle typically has several small holes distributed in different directions, with the main function of spraying out steam.

When we disassemble the nozzle, we can see a straw-like white tube through which steam is delivered.

Because the nozzle has few and small holes, the amount of steam that can pass through is limited. However, since the coffee machine continuously delivers steam, the accumulated steam forms a powerful thrust, forcing the steam to be "pushed" out extremely quickly. This type of steam can create a vortex in milk during frothing, breaking large bubbles into countless tiny bubbles, resulting in fine and silky foam. Therefore, we can understand that the holes in the nozzle are critically important. When we find that the steam from the coffee machine's steam wand has weakened without any machine malfunction, this means the small holes in the nozzle have become blocked. Because of the blockage, the steam becomes weaker. The main culprit behind this blockage is milk residue that wasn't properly cleaned after frothing milk.

The Cleaning Process

As we know, milk contains many rich substances. When we finish frothing milk, if any milk remaining on the steam wand isn't cleaned thoroughly, the water content in this milk will evaporate due to the nozzle's high temperature, leaving behind substances that couldn't evaporate and attach to the steam wand, forming the visible milk scale. Because this milk scale exists in solid form, when it appears in the steam wand holes, it causes blockage. With limited outlets, the steam cannot be discharged quickly, thus weakening the steam intensity. In such cases, we need to clear the nozzle holes to restore steam strength. This cleaning process involves two steps. The first step is to use a needle-like sharp object to poke out the milk scale blocking the holes. Since it was able to block the nozzle, it has accumulated a certain thickness, and without this initial clearing, the subsequent step won't be effective.

After using a sharp object to clear the milk scale from the channels, take our coffee machine cleaning powder, scoop a small spoonful into a prepared glass, add an appropriate amount of hot water, and place the nozzle inside to soak for several hours. Overnight soaking is also acceptable.

After soaking is complete, take it out, clean it thoroughly, and reattach it to the coffee machine's steam wand. The nozzle cleaning is then complete, and the steam should return to its original strength. Since this type of cleaning is rather tedious, we don't need to do it daily—once a week is sufficient. However, we also shouldn't forget daily cleaning when using the coffee machine. Before and after each milk frothing session, we need to purge the steam wand to clear any residue from inside the nozzle.

In addition, prompt wiping after use is necessary to prevent milk scale formation. As long as cleaning is done properly, the nozzle naturally won't be as prone to blockage.

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Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473