Chinese masons used to make mortar using sticky rice. The practice originated at least 1500 years ago.
The secret ingredient that makes the mortar so strong and durable is amylopectin, a type of polysaccharide, or complex carbohydrate, found in rice and other starchy foods, the scientists determined. The mortar’s potency is so impressive that it can still be used today as a suitable restoration mortar for ancient masonry.
(via history blog)