The Food Lab: Better Home Cooking Through Science

First question: Which type of rice makes the best risotto?
Rice contains two molecules that make up its starch
content, amylase and amylopectin. Generally speaking, rices
with a higher proportion of amylopectin to amylase will tend
to soften more completely and thicken their sauce more
strongly. All risottos start with a short- to medium-grain
form of rice high in amylopectin. It’s the exact ratio of
amylase to amylopectin that determines the final texture of
your rice and sauce.
There are dozens of cultivars of short-grained rice used in
Italy, but here in the United States, you’re likely to see only
four types that’ll work for risotto: