Ok so you just received your new semi-automatic machine and are getting ready to make a nice cappuccino. You have watched the local Barista, done your online research and have quickly come to the conclusion that you are getting conflicting information on how to properly make a cappuccino or latte with your new machine. In some instances, you may have seen the drinks being made by brewing your espresso and then steaming and frothing your milk. Likewise, you may have also watched videos that show a latte being made in a glass cup where the espresso is being poured into the steamed milk. So which is it you might ask. "Do I brew first or do I steam first"?
The consensus with our team here is that it is better to steam/froth your milk first and then brew your espresso. This especially holds true when using a single boiler espresso machine like the Gaggia Classic or Rancilio Silvia. This serves three main purposes:
First, it is much more fast to make a latte or cappuccino by cooling the machine to brew after steaming then to wait for the machine to heat to steam after brewing. You can very quickly have the machine ready to brew simply by switching to the brew button and running hot water through the steam arm. The wand will change from producing steam to producing hot water very fast. Once you have hot water instead of steam you are ready to brew. This should take mere seconds with most mid level semis like the Gaggia machines.
Second, it is better for the machine and its internal components to be at the cooler brew temperature then the hotter steam temperature. In fact, Rancilio states in their manual that the steps mentioned in point one is necessary in the normal operation to prevent the machine from burning out heating elements and boilers.
Third, performing step one with the mid level semi-automatic machines is a great way to maintain a relatively consistent temperature when brewing. If you start brewing at about the same time after the steam turns to hot water you can maintain a consistent brew temperature with every shot. This is something known as temperature surfing which is a topic all of its own.