Sugar, the common name for sucrose (also saccharides), is extracted and refined from sugar cane and sugar beets. There are many substance chemical classified as sugars, and when these are referred to, they are always used with a qualifier such as in milk sugar (lactose), corn sugar (dextrose), and malt sugar (maltose).
When the word sugar is used without qualifier in, generally refers to the common sweetener (sucrose). Other sugars have varying degrees of sweetness relative to sucrose, and some sugars differ from sucrose in that they lend varying degrees of bitterness whereas sucrose imparts only a sweet taste.Other important sources of sucrose include palm and maple trees and fruits. Chemically, and in every other way, cane sugar and beet sugar are the same. In addition to providing energy for the body and sweetness to foods, sugars perform numerous other roles in the food industry.
Sucrose is actually composed of glucose and fructose, and it is structurally unique in that its glycosidic bond involved the anomeric hydroxyl of both residues. The linkage is alpha with respect to the glucose and beta with respect to the fructose residue.
The dietary sugars that are most important nutritionally since free monosaccharides are not commonly present in the diet in significant quantities. There is, however, some free glucose and fructose on honey, in certain fruits, and in the carbohydrates that are added to processed foods. The cellular use of carbohydrates depends on their absorption from gastrointestinal (GI) tract into the blood stream, a process normally restricted to monosaccharides. Therefore the sugars must be hydrolyzed to their constituent monosaccharides units. The hydrolytic enzymes involved are collectively called glycosidase, or, alternatively, carbohydrases.
Sugar in the Diet
