Foam after oaking ?

[1131morg]

Just curious. I oaked about 32 ounces of 140 proof in quart jar for about 30 days. Beautiful color and smells great. I ran it through a coffee filter into another jar and then into a bottle. In the bottle I noticed some foamy stuff on top. I figured it was from the bottle. I then washed the bottles and still have it. Lookin into the jars I noticed it before I bottled it. Could this be from the oak or something else ?

[Roundyround]

how much and what form of oak did you use?

[googe]

I've noticed that to and wondered, and my oaked rum gets a head on it and the white rum doesnt when I mix with coke. I always thought it was the Tanins being realised from the timber that caused it?.

[1131morg]

Its not much but is enough to notice. I fill the jar bout 1/4 full with chips then rest of way with liquor. As for what type, not sure. Just regular dried white oak I presume

[Dnderhead]

"1/4 full with chips then rest of way with liquor"
wood soup?

[heartcut]

10-20 grams of wood chips per qt works for me.