I am using Flextanks and oak chips for my wine and am really liking the results…

Like you I find oak pieces (segments, beans and sometimes chips) are a great way to practice elevage (aging and development) with small lots that won’t fit into a 60-gallon (227-L) barrel or for larger lots where I just don’t want the hassle of barrels. If you’re using small pieces of wood in winemaking, you guessed it, it’s a heck of a lot easier to work with them if you confine them to a bag or a sack of some kind. My non-coopered oak supplier of choice, Stavin (based in California) packs their oak beans and segments in food-grade nylon bags. These puppies are big however, weighing in at 20 lbs. (9 kg) each and are way too large for most home winemakers.
   
So get creative with your oak bagging! I shop at my friendly home winemaking store in Napa and (gasp!) even meander over to the brewing section to pick up some food-grade nylon mesh bags of various sizes. Friends of the Wiz use them for infusing hops or grain in their brews but I use them for containing my oaky bits. You can also find these bags online, again through home winemaking and homebrewing websites.
   
Don’t want to buy something new? I’m not sure if the nylon you mention above is technically “food grade” but in a pinch I’ve known people to use nylon stockings, loose-weave, undyed cotton fabric like muslin (all natural material so nothing will leach into the wine) or several layers of cheesecloth (undyed cotton).
   
If your chips are small, a very loose-weave fabric like cheesecloth will definitely need to be layered several times to keep any little oak pieces from coming out and getting into your wine. Simply measure out how many oak chips you need (I tend to figure, for young red wine, starting with 2 g/L ), cut enough fabric to hold them (you can even split up your dose into two bags if you are adding a lot) gather up the oak into a ball and secure with undyed cotton twine, fishing line or other strong neutral tying material and suspend the ball in your wine. If I’m making wine in a small stainless steel tank with o-rings welded on the inside, I’ll actually tie the ball to the o-ring before filling the tank. This keeps the bag submerged in the wine, where it will do the most good. Also, you can weight your bags with spare stainless steel fittings, clamps or endcaps — I always have a few spares hanging around the garage because they’re what I use to seal my small stainless topping kegs.
   
Just make sure that whatever you put into your wine won’t leach anything or break off into small pieces. Stainless steel is safe, as are “food grade” plastics, non-lead ceramics and pyrex. As far as the oak pieces or chips go, make sure that you shop around and try lots of different brands. I have found large differences in quality between suppliers; some products seem to be nothing more than the sweepings from the barrel shop floor! Don’t forget that the smaller the oak particles, the faster the wood character will extract and, in my experience at least, the harsher the finished product. For longer-term aging, try bigger segments (around 2 inch X 0.5 inch/5 cm X 1 cm). Suppliers are coming up with new types of non-coopered oak all the time so keep checking in.

Response by Alison Crowe.