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How is galactose produced from lactose?

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Tall, dense stalks of sugarcane grow on both sides of a narrow path, with green leaves arching overhead and sunlight illuminating the plants. — sugar Lines of sugarcane before harvest.

Lactose, a disaccharide found in the milk of mammals, is composed of one molecule of glucose and one molecule of galactose linked by a $β$ -linkage.12

To produce galactose from lactose, the glycosidic bond connecting these two simple sugars must be cleaved. This process is catalyzed by lactase, an enzyme located in the small intestine of mammals. By breaking down the lactose molecule, lactase allows the body to separate and absorb the individual monosaccharides, glucose and galactose.23