How can rice turn into pudding or sushi?

Shake a bag of dry rice and listen to it rattle, shh, shh, like tiny pebbles. Each grain feels small and smooth between your fingers. Those crunchy little grains do not look much like dinner yet.

Yet the very same rice can become a bowl of warm, creamy pudding. It can also become sushi, bites of rice that hold their shape around fish or cucumber. How can rice turn into pudding or sushi?

The secret is packed inside every grain. Each grain is full of starch, which means the white food that a plant stores inside its seeds. In dry rice, the starch is packed so tightly that the grain stays hard.

To start, a cook puts the rice in a pot with hot water or milk. The heat helps the liquid seep into each grain, and the starch soaks it up like a sponge. As the starch swells, the grain grows plump and soft.

Some of the starch slips out onto the outside of the grains. This loose starch is sticky, so the grains cling to each other. Both pudding and sushi need that stickiness.

For pudding, the cook keeps the rice bubbling gently in the milk and adds a spoonful of sugar. The sugar makes it sweet, and the slow heat gives the grains time to turn very soft.

As the cook stirs, the loose starch spreads into the milk and thickens it. The milk turns creamy around the soft grains, and that sweet bowl is rice pudding. A sushi cook makes plain rice in water instead. What do you think the sushi cook stirs into it?

The sushi cook mixes in rice vinegar, with a pinch of sugar and salt. The vinegar gives the rice a bright, tangy taste, a perfect match for fish and seaweed.

Once the rice has cooled, the cook presses a small handful with damp hands. The sticky starch holds the grains together, so the rice keeps its shape. Then the cook tops it with a slice of fish, and there is sushi.

So, our key word is starch. When a cook heats rice in water or milk, its starch soaks up the liquid and makes the grains soft and sticky, and then milk with sugar makes pudding while vinegar makes sushi.

The next time you eat a spoonful of rice, you will know the secret hiding in every grain that makes it soft and sticky.