While wine certainly does contain a small amount of dissolved protein (naturally coming from the grapes or other fruits — fruits do not contain gluten)and we do not add products that contain gluten to wine. I’ve read some pretty panicked posts on the Internet about fear of barrel-makers using a wheat-based paste on the barrel heads during barrel construction. I’m not sure if any barrel-makers still do this and I called our barrel companies and they thought I was nuts.
If you want to avoid gluten in wine from this extremely remote possible (in my opinion highly unlikely) source, stick to wines that probably haven’t seen any barrel time, like Vidal Blanc, Riesling and Pinot Grigio.
Beware of commercial wines being marketed heavily as “gluten-free.” The American Dietetic Association considers wine and most alcoholic spirits to be safe and so wines hyping their “gluten-free” status maybe just trying to find a unique marketing angle but having no scientific justification just like labeling water as gluten-free. However, since I’m not a doctor, I encourage everyone with Celiac Disease to do your own research. At Nashoba, I can attest that we do nothing that would add gluten to our wines. Additionally, our brewery is in a separate building and uses separate equipment to avoid any possibility of cross-contamination.