The sugar present in milk is primarily lactose.
Composition
Lactose is a disaccharide composed of two monosaccharides:
- Glucose
- Galactose
The molecular formula of lactose is C₁₂H₂₂O₁₁.
Linkage
Lactose is formed by a β-1,4-glycosidic bond between the anomeric carbon (C1) of β-D-galactose and the C4 of β-D-glucose. This linkage is crucial for the sugar's properties and how it is metabolized in the body.
Function
- Energy Source: Lactose is a source of energy for infants and others who consume milk. It is broken down into glucose and galactose by the enzyme lactase, which can then be utilized by cells for energy.
- Facilitates Calcium Absorption: Lactose enhances the absorption of calcium and possibly other minerals, which is crucial for bone health, especially in growing children.
- Prebiotic Effect: Some studies suggest that lactose has prebiotic properties, promoting the growth of beneficial gut bacteria in the intestines.
- Flavor and Texture: In dairy products, lactose contributes to the flavor profile and can also influence the texture and mouthfeel of products such as yogurt and cheese.
In summary, lactose plays vital roles in nutrition, digestion, and provides various health benefits related to calcium absorption and gut health.