Infuser

An infuser is any removable tool, basket, mesh ball, spoon-style strainer or disposable paper filter bag, used to hold loose leaves inside a mug or pot while the water steeps around them. When the steep is done, you lift the infuser out instead of straining the whole pot.

The way it is built matters: fine mesh keeps small leaf particles out of the cup, while a roomy basket lets whole leaves swell and unfurl, which is when they release most of their flavor and aroma. A tight, cramped infuser restricts that expansion and holds a tea back from tasting its best.

When buying, match the infuser size to the tea style, since large-leaf oolongs and whole-leaf whites need noticeably more room than fine black tea or rooibos. A very common mistake is packing a small ball infuser tightly with leaf, which stops the leaves expanding and produces a weaker, flatter cup than the same tea brewed with more room.