How Leftover Milk Ruins the Drink and the Espresso Machine
The obvious benefit that the milk system of a super automatic espresso machine offers is unmatchable convenience. Especially since its programmable features can be set to the correct coffee to milk ratio for any drink on the menu. This becomes most valuable for coffee shops in a morning rush, or locations without a dedicated barista like a restaurant, convenience store or office. But no matter where or how a super automatic machine is used, it can fall prey to neglect, and the milk in your dairy-based drinks will go sour. Literally.
The issue that will occur first is milk drying up in the milk lines. Milk is an excellent source of a variety nutrients, including proteins and fats, which makes it an ideal environment for bacteria to grow. It is also a slightly acidic substance, and becomes more acidic over time, so it turns sour quickly if it’s not refrigerated. Which means each subsequent dairy-drink prepared with dirty milk lines could have old, rancid, sour milk in the cup. Not how a latte should taste.
A longer term problem that will arise with automatic milk systems is mineral scale buildup. Water makes up 87% of milk’s overall composition, and it contains minerals like calcium that contribute to the accumulation of lime scale. This scale will affect the taste of your milk beverages, and if left to build up over time, can ruin the internal mechanisms of a machine. Mineral scale is a hard substance that requires a unique chemical formula that typical cleaning products don’t contain.