Have you ever put leftover soup in the fridge, only to find that it has turned from a liquid into a thick, slimy mass of jelly after it cooled? Have no fear: your soup has simply congealed!
When a liquid has congealed, it becomes thick and gelatinous, like when gravy cools off or blood dries. This process happens when substances cool down and solidify, changing their texture and form, which can be fascinating in both cooking and science — if a bit unappetizing. Luckily, most congealed foods can become tasty and appealing once more by simply heating them up.