lactose

3 definitions found

lactose - Collaborative International Dictionary of English v.0.48 :

  Galactose \Ga*lac"tose\, n. (Chem.)
     A white, crystalline sugar, C6H12O6, isomeric with
     dextrose, obtained by the decomposition of milk sugar, and
     also from certain gums. When oxidized it forms mucic acid.
     Called also lactose (though it is not lactose proper).
     [1913 Webster]

  lactose \lac"tose`\ (l[a^]k"t[=o]s`), n.
     1. (Physiol. Chem.) The main sugar present in milk, called
        also sugar of milk or milk sugar. When isolated pure
        it is obtained crystalline; it is separable from the whey
        by evaporation and crystallization. It is a disaccharide
        with the formula C12H22O11, being chemically
        4-([beta]-D-galactosido)-D-glucose. It has a slightly
        sweet taste, is dextrorotary, and is much less soluble in
        water than either cane sugar or glucose. Formerly called
        lactin. When hydrolyzed it yields glucose and galactose.
        In cells it may be hydrolyzed by the enzyme
        [beta]-galactosidase.
        [1913 Webster +PJC]
  
     2. (Chem.) See Galactose.
        [1913 Webster]

lactose - WordNet (r) 2.1 (2005) :

  lactose
      n 1: a sugar comprising one glucose molecule linked to a
           galactose molecule; occurs only in milk; "cow's milk
           contains about 4.7% lactose" [syn: lactose, milk sugar]