<<Disclaimer: Verify this information before applying it to your situation.>>

Coincidentally, this weekend I too was trying to find out the ingredients of
port. I went to www.premiumport.com, the website for Premium Port Wines Inc.
They are the national importer of Graham's, Dow's, Smith Woodhouse and
Quinta do Vesuvio Ports, as well as Leacock's, Cossart Gordon and Blandy's
Madeiras. Below is their response to the question I e-mailed to them from
their site. (Today they contacted me again to say that they would post my
question and their response on their website, because they thought the
information would be useful for other people too.)

--Nancy E. from New York City


Dear Nancy,

Port - that is true port from Portugal - is fortified with neutral grape
spirit only. Spirit distilled from grain is not permitted. We cannot
give you any assurance as to the type of fortifying spirit used by
producers from any other region who use the name "Port" on their wines
(e.g. California, South Africa, Australia) but if you do consume only
true port from Portugal you will be consuming a product produced 100%
from the grape.

Madeira - again we refer only to true Madeira from the Portuguese island
- was formerly often fortified with cane-sugar spirit but this practice
was banned in 1967. Now only grape spirit is used. If you are unable to
tolerate cane-sugar spirit you should avoid any older Madeira. If
cane-sugar distillate poses no problem you should have no concern with
any true island Madeira. Again, we make no claims for products produced
elsewhere than on the island of Madeira hence I urge you to be sure that
you consume only Portuguese products.

I hope this helps,

Best regards.

David Campbell
Premium Ports and Madeiras