I'd doubt this because the rate of de-complexation is usually pretty low (which is why it's useful as a mechanism for slowed drug delivery -- the cyclodextrin-complexed compounds move around much more easily than the usually-hydrophobic drug de-complexes from the cyclodextrin).
Edit: reading the application -- this doesn't appear to be cyclodextrins, but some configuration of small-chain length glucose polymers (mentioned 1-20 with an average of 10).
It looks like the powder is made by a physical process. Just as water absorbs into a towel. Ethanol apparently absorbs into dextrin powder and stays as a dry solid.
From the patent:
EXAMPLE II A 150 g. amount of the bulked 5 DE. MOR-REX dextrin of Example I was blended with 250 g. of 90% by weight water) ethanol in a Hobart mixer at speed No. 2 with a wire whisk for 2 minutes. A dry-tothe-touch free flowing powder was obtained that contained 56.2% ethanol and 8.3% moisture. The bulked ethanol containing flowable powder was packaged in air-tight foil envelopes and after 6 months storage had retained its flowability characteristics and its original alcohol content.
EXAMPLE III A teaspoonful (3 g.) of the product of Example II, when added to 10 ml. of water produced a clear, sparkling low-viscosity alcoholic solution with a nonsweet strong alcohol taste.
[1]:http://www.google.com/patents/US3795747