Recap and Glossary
- Baristas are responsible for monitoring the pressure gauges on espresso machines.
- If ever the steam boiler’s pressure gauge reads dangerously high (i.e., over 2 bars), immediately switch off the machine and contact a qualified person to deal with the issue.
- Steam boilers are usually set at between 1.0 and 1.5 bars of pressure.
- Purging the steam wand before and after steaming is essential to prevent syphoning and to avoid adding old steamed-milk residue to the next pitcher of milk to be steamed.
- Steaming milk to produce microfoam can be achieved by a two-step process: entraining air into the milk before the milk gets warm and, in doing so, increasing the milk volume by a factor of one-third.
- Milk should be aerated between 20–50% for all milk-based drinks on the menu (except the cappuccino).
- Non-dairy milks are prone to curdling, and it is necessary to use techniques to avoid this.
- Milk should not be heated to below 55° C or above 65° C.
- Colour-coded cloths will help to avoid cross-contamination of milk and equipment.
- An organised milk-splitting protocol can help you achieve an even division of foam between drinks of the same type. Steaming milk for more than one drink at a time is more efficient than steaming individually for separate drinks.
Boiler pressure The steam pressure built up in a sealed water boiler, used for producing steam
Cross-contamination A situation in which chemicals or high-risk food types are mixed with each other in a way that is detrimental to their safe storage or renders them unsafe to consume
Curdling A process that causing milk (dairy or non-dairy) to separate into curds or lumps
Entrain To incorporate air into milk
Four Quarters Method A system of milk-splitting that is designed to share equal amounts of foam between two drinks
Lipase enzyme An enzyme that occurs naturally in milk that,