When yeast (wild, in this case) is cut off from the oxygen, alcohol is produced which is the brown/black liquid pooling on the top of your starter. I am pretty certain the liquid in your case, is not black but only slightly brown after such a short time of 5 hours. In either case, no problem. Just stir it down for a tangier flavor. It is not recommended to use several discards in one recipe. The product will come out heavy and dense. If you are not planning to use the discard immediately, store in the frig for up to 3-4 days. The longer you wait, the more spent it will become. Consider freezing it! Elisabeth@KAF

• Reply