Bayhaqi 11201 — Pledged juice that turns into wine leaves the pledge

It is narrated from Aslam (may Allah have mercy on him), the freed slave of Sayyiduna Umar bin al-Khattab (may Allah be pleased with him), that tila' (thickened cooked grape juice) was brought to Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) at al-Jabiyah. In those days it was cooked until it was like thick syrup. He said: This is indeed a (permissible) drink at the stage it has reached. The vinegar of wine that has been spoiled (deliberately) is not to be drunk until Allah Himself makes its spoiling appear; at that point the vinegar becomes good. And there is no harm for a person to buy vinegar he finds with the People of the Book, as long as he does not know that they deliberately spoiled it after it had turned into wine.
His word "spoiled" means: treated (to turn it into vinegar).