Kosher wine (Hebrew: יין כשר, yáyin kashér) is wine that is produced in accordance with halakha, and more specifically kashrut, such that Jews will be permitted to pronounce blessings over and drink it. This is an important issue, since wine is used in several Jewish ceremonies, especially those of Kiddush.
To be considered kosher, Sabbath-observant Jews must supervise the entire winemaking process and handle much of it in person, from the time the grapes are loaded into the crusher until the finished wine product is bottled and sealed. Additionally, any ingredients used, including finings, must be kosher. Wine that is described as "kosher for Passover" must have been kept free from contact with leavened or fermented grain products, a category that includes many industrial additives and agents.