Malt vinegar, or alegar, is a type of vinegar which is made by malting barley, turning the barley into a beer, and then allowing the beer to turn into vinegar. The flavor of malt vinegar is quite distinctive, and very familiar to many fans of fish and chips. In addition to being used as a condiment, malt vinegar is also commonly used in chutneys, and it can be added to pickling mixtures. The strong flavor makes malt vinegar less suitable for more mild, delicate sauces and dressings.

When barley is malted, it is soaked in water and allowed to germinate before being roasted to dry it out. The partial germination and roasting converts the natural starch in the barley into a sugar which is known as maltose. When the malted barley is fermented, the maltose will convert to alcohol. The malting process is used to make beers and an assortment of liquors such as whiskey. When the malted mixture is fermented in a special way, the alcohol turns to vinegar, which has a high concentration of acetic acid, giving it a distinctive tangy taste.

Most malt vinegar is light brown, and it is often aged before sale to allow it to mellow. Fresh malt vinegar can have a raw, assertive, aggressive taste which is a bit intense, while well handled aged malt vinegar is creamy and soft. The acidity pairs with the distinctive malted flavor to create a very unique condiment. Unfortunately for fans of malt vinegar, some companies make imitations of this popular vinegar which are dyed with ingredients like caramel; these products may be labeled as malt vinegar, but they lack the complex, layered character of true malt vinegar.

If you plan to use malt vinegar for pickling, make sure that the acid content is around 5%. This concentration is ideal for pickling, and it will ensure that the food is safely preserved by the pickling process. If you want to use this vinegar as a condiment, you may want to seek out a genuine malt vinegar if you are going for the trademark malty flavor.

The strong flavor of this vinegar means that it is not usually suitable for the purpose of making herbed or flavored vinegars. At best, a flavored vinegar made with malt vinegar will simply be overwhelmed by the malt, and at worst the added flavoring could clash with the malt vinegar in a rather unpleasant way.