Corn syrup

From Wikipedia, the free encyclopedia.

Corn syrup is a syrup made from maize, composed mainly of glucose. It is used to sweeten soft drinks, juices, ice cream, and many other mass-produced foods. Its liquid form keeps foods moist and prevents them from quickly spoiling. In many areas it is less expensive than sugar due to agricultural policy, e.g. the United States subsidizes its production while taxing sugar imports.

A variety of corn syrup called high fructose corn syrup is often used to cheaply improve the flavor of food. A portion of the glucose in ordinary corn syrup is converted to fructose through the incubation with the enzyme glucose isomerase. This process, invented by Japanese researchers in the 1970s, increases the fructose content of corn syrup to 42%. Because fructose is a much sweeter monosaccharide than glucose, the sweetness of the syrup increases relative to corn syrup. Fructose is also more desirable than glucose as it increases in solubility at low temperatures (so more can be concentrated per unit weight). Through further processing, the fructose content can be increased to 55% (yielding a product that has the same sweetness as sucrose) or any desired higher amount. Common commercial grades of high fructose corn syrup include grades having 42%, 55%, or 90% fructose.

The cheapness and abundance of high fructose corn syrup has generated opinions that the substance has a propensity to induce Type II Diabetes. While this is generally accepted as true, it is misleading, because "normal" table sugar (sucrose) is also widely implicated as a cause of diabetes. Once ingested, sucrose is quickly converted to glucose and fructose by the enzyme invertase.