Tamari is made with more soybeans than ordinary soy sauce, resulting in a smoother, more balanced, and complex flavor. In the 17th and 18th centuries, the manufacturing of soy sauce developed from a household art to a commercial industry. To increase production, the thick, whole soybean mixture was replaced with a mixture of half wheat and half soybean. The new liquid resulting from fermentation became known as Shoyu, the common type of soy sauce used today.
Three main categories of soy sauce are available in the United States: Tamari, naturally brewed and made primarily with soybeans; Shoyu, also naturally brewed and made from half soybean and half wheat; and Nonbrewed, which is made from hydrolyzed vegetable protein.
When judging soy sauce, the characteristics to look for are aroma, appearance, and most importantly, taste. Tamari has a soft, rich aroma; a very smooth flavor; and a well-balanced taste. Shoyu, although a modern-day brewed soy sauce with a balanced taste, is sharper than Tamari due to the difference in raw materials and a stronger alcoholic fermentation. Nonbrewed has a strong, unbalanced taste; a salty aftertaste; and is completely unlike Tamari and modern-day brewed soy sauce.
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