How many molecules of water would be needed to break apart a polysaccharide molecule made up of 20 simple sugars and what is the process called?

The process to break apart polysaccharide would be called hydrolysis as the reaction need water. A water molecule will be able to break one bond. Polysaccharide made by 20 simple sugar should have 19 bonds. If we need one molecule per bond, then it should need 19 molecules of water to completely break the polysaccharide into monosaccharide.