in Europe, with the French city of Orléans becoming particularly famous for the quality of its vinegar through a formalized fermentation and aging process, which became known as the Orléans process. During this time, malt vinegar also began to develop in England, where it was first known as alegar. Balsamic vinegar also began its evolution in the Duchy of Modena in Italy, though it would not become widely known until the Napoleonic Wars after being sold abroad by French troops. In the 19th century, vinegar production underwent many dramatic changes, such as rapid industrialization and scientific analysis. Karl Sebastian Schüzenbach invented the first large-scale industrial process for vinegar production in the Kingdom of Baden in 1823. Known as the packed generator, it circulated alcohol over beechwood shavings to reduce fermentation times from several months down to 1–2 weeks. This process also facilitated the rise of vinegar made from pure alcohol called spirit vinegar or distilled white vinegar. Japan also began industrializing vinegar production during the last days of the Tokugawa shogunate, when Matazaemon Nakano, a man from a traditional sake brewing family, discovered that sake lees could be used to make rice vinegar. This helped provide ample vinegar for the burgeoning popularity of sushi in Japan. The company he founded, now known as Mizkan, is headquartered in Handa (near Nagoya) and is the largest vinegar producer in the world. Meanwhile, vinegar fermentation became understood as a natural and biological process. Louis Pasteur made the decisive discovery that a special type of bacteria, later known as acetic acid bacteria, was the agent of fermentation for vinegar production. In the 20th century, vinegar production was again revolutionized by the invention of the submerged fermentation process that cut production times down to 1–2 days. This allowed the mass production of cheap vinegar around the world. Production Commercial vinegar is produced either by a fast or a slow fermentation process. In general, slow methods are used in traditional vinegars, where fermentation proceeds over the course of a few months to a year. The longer fermentation period allows for the accumulation of a nontoxic slime composed of acetic acid bacteria and their cellulose biofilm, known as mother of vinegar. Fast methods add the aforementioned mother of vinegar as a bacterial culture to the source liquid before adding air to oxygenate and promote the fastest fermentation. In fast production processes, vinegar may be produced in 1-3