Do disaccharides undergo anomerization?
Not only is there no reason to think anomerization does not occur in the disaccharide you mention, it most definitely does occur. 

As long as water has access to carbon-1 of a glucose unit, there will be an open-chain form at that site, and then when it re-closes, the possibility of alpha- and beta-anomers.  This will be the case for di-, tri- tetra-, oligosaccharides, polysaccharides, etc... and applies to monosaccharides of any carbon length or type (aldoses or ketoses).  

The reason is that hemi-acetals or hemi-ketals are intrinsically unstable in water. By contrast, when that carbon is a full acetal or full ketal (a so-called non-reducing sugar) then it is stable in water, and anomerization does not occur.  Examples include trehalose and sucrose.