Wooden barrels can be with galvanized or black rings.

To reduce the effect of wood barrel tannins, you should do the following:

1. Fill the barrel with hot water, let the water cool, then empty the barrel.
2. Fill the barrel again, this time with cold water, let the water temperature rise to room temperature and empty the barrel again.
3. You will notice that during the first few flushes, black or brown water comes out of the barrel. That’s why you have to fill the barrel a few more times, until clear water starts coming out of it.
In this way, the level of tannins from the oak will be reduced and will have less effect on the alcoholic beverages that you will keep in the barrel.
If you want an even lower tannin level, repeat the cold water rinse several times. It is important to note that there is a possibility that a brand new barrel will leak at first, even for the first few days. This is completely normal, because during filling the rainbows expand and adhere better to each other and thus seal the barrel.
If you leave the barrel empty, after a few weeks the rainbows will start to shrink again and in that case you need to refill the barrel with cold water to spread them out. When filling the barrel with water, do not use caps.