Even absent any obvious smudges or smears, beer professionals can tell just by looking if a beer has been poured into a dirty glass. The trick is to pay attention to what the bubbles are doing.

The glass adds to the tactile facet of the experience, while the shape of the glass itself can augment the flavor of the beer it holds. [ Hello, inbox: Sign up for the weekly Things To Do newsletter .

That's why fancy beer glasses often have etching in the middle of the bottom, so that you get a cool cascade of bubbles coming up to the top and reinforcing the foam. Photograph: Parker Hall.

From ocean depths to kitchen shelves, microplastics have infiltrated nearly every corner of the environment. They’ve been found in food, water, soil, air, household dust, and even human waste. This ...

Apart from the visual cues, beer in dirty glassware can sometimes have an off-aroma, which Smith describes as a “wet dog smell.” A funky-smelling beer is going to be markedly less enjoyable.

A clean glass, Hobday said, “allows for residual foam to stick to the walls as you drink your beer, forming a lace-like pattern of parallel rings on the empty glass.” A beer with no head, a head that ...