What should be done to the steamer wand before steaming milk?

Before steaming milk, it is essential to sanitize the steamer wand. This practice ensures that any residual milk or bacteria from previous use is removed, making the wand safe for use with fresh milk. Proper sanitation helps maintain hygiene standards and prevents contamination, which can affect both the taste of the milk and the overall quality of the beverage being prepared.

Sanitizing the steamer wand typically involves running steam through it to clean any remaining bacteria and then wiping it down with a clean cloth. This step is crucial in a professional setting like Starbucks, where food safety and cleanliness are paramount.

While other actions like cooling down or adding water may relate to different aspects of preparing espresso or steaming milk, they are not necessary as a preliminary step specifically before steaming milk. Similarly, oiling the wand is not appropriate or safe, as it can introduce foreign flavors and residues into the milk. Therefore, sanitizing is the most critical step to ensure a clean and safe steaming process.