It has been discovered that fracturing fluid breaker mechanisms are
improved by the inclusion of a catalyzed polyol alone that directly
degrades the polysaccharide backbone, and optionally additionally by
removing the crosslinking ion, if present. That is, viscosity reduction
(breaking) occurs by breaking down the chemical bonds within the backbone
directly. The gel does not have to be crosslinked for the method of the
invention to be successful, although it may be crosslinked. In one
non-limiting embodiment, the polyol has at least two hydroxyl groups on
adjacent carbon atoms. In another embodiment, the polyols are simple
sugars and sugar alcohols, and may include mannitol, sorbitol, glucose,
fructose, galactose, mannose, lactose, maltose, allose, etc. and mixtures
thereof. The catalyzing metal ion may employ a metal selected from Groups
VIB, VIIB, VIII, IB, and IIB of the Periodic Table (previous IUPAC
American Group notation).