A sour tasting seasoning and preservative that has been around as long as wine. If you do not prevent it, it will always turn into vinegar in the end. This was already used as a drink in ancient times, mixed with other ingredients. A medical application for respiratory and digestive disorders has been handed down by Hippocrates (460-377 BC). The Roman author Columella (1st century) reports in his work "De re rustica" about the vinegar production from figs, barley and wine. Vinegar has played a role in many cultures. In the Bible vinegar is mentioned as a staple food, the Egyptians had "hequa" (vinegar drink made from barley beer), the Babylonians used vinegar water as a refreshing drink, the Phoenicians made their sour shekar from cider, the Greeks used it in sacrificial ceremonies, the Roman legionaries protected themselves from colds with the Posca (vinegar water) and in Japan the traditional Tamago-Su (rice vinegar) is known, in which a raw egg is dissolved. In the Middle Ages, herbal vinegar was considered a remedy, Hildegard von Bingen (1098-1179) and Nostradamus report on this. The plague vinegar was used against this epidemic.
The causes of its creation were unknown until the middle of the 19th century. The French chemist Antoine Laurent de Lavoisier (1743-1794) claimed in 1793 that this was an oxidative process. In 1837, the German botanist Friedrich Traugott Kützing (1807-1892) correctly named microorganisms as the cause. But it was not until 1868 that the French chemist Louis Pasteur (1822-1895) was able to prove this and identified bacteria as the cause. In the simplest case, "leaving" any alcoholic liquid to stand is sufficient. When such liquids are exposed to air, wild acetic acid bacteria often settle automatically. This is also how the first vinegars were created by chance. Although the process is often referred to as acetic acid fermentation, it is actually a fermentative process because, unlike fermentation, oxygen is required. Many liquids containing alcohol can serve as a basis. These are beer, cider, malt stock, rice wine, grape must or wine.
According to Austrian food law, vinegar is a liquid suitable for human consumption, in particular for acidifying and preserving food, which is produced either by the process of double fermentation, namely alcoholic and vinegar fermentation, or by diluting acetic acid suitable for consumption with water (acid acetic acid). The total acidity, calculated as acetic acid, must be at least 5 g in 100 ml, or at least 6 g in 100 ml for wine vinegar. The alcohol content must not exceed 0.5% vol., or 1.5% vol. in the case of wine vinegar. However, the nature of the vinegar depends not only on its acetic acid content, but also on the raw material and any additives which may have a negative impact on the taste. Apart from acetic acid, vinegar contains only those organic acids that originate from the raw material used or are formed during production.
The oldest process is called open or also Orléans process. In this process the source liquid is inoculated with bacteria. However, the bacteria would also colonise automatically from the air and can also be transmitted by the vinegar fly. The fermentation process is left to itself in open vessels in a warm environment. After some time, a gelatinous, thread-forming skin (also called vinegar cream) of bacteria forms on the surface of the liquid. The acetic acid bacteria(Acetobacter) oxidise alcohol to acetic acid, whereby acetic acid ethyl ester (ethyl acetate) is also formed. The German vinegar producer Johann Sebastian Schützenbach introduced the rapid acetic acid process in the middle of the 19th century. This process uses floating carrier material (wood chips or plastic beads) on which the bacteria adhere. As a result, more bacteria develop and thus the process is faster.
Depending on the technology used, production takes two to three days using the Venturi method (mixing of liquids) or, in turbine systems, even within 24 hours. The starting product is fermented at 28 to 30 °Celsius and gassed with air. As a rule of thumb, the alcohol content of a wine also results in the same amount of acetic acid (12% alcohol content = 12% acetic acid). Table vinegar or table vinegar contains 3 to 10% acidity, the vinegar essence that can only be enjoyed diluted contains 60 to 80%. Wine vinegar is a great enrichment in the production of food or for direct consumption. Sweet and sour drinking vinegar from highly noble predicate wines is served as an aperitif or digestif, matured sherry vinegar is used in the kitchen or the Italian speciality balsamic vinegar is used to refine meat, cheese or desserts. However, the combination of vinegar in salads and wine is problematic and can lead to an "acid explosion" in the mouth. See also under wine with food.
Complete lists of the numerous vinification measures and/or cellar techniques, as well as the different wine, sparkling wine and distillate types regulated by wine law are contained under the keyword vinification. Comprehensive information on wine law can be found under the keyword wine law.
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