Oyster sauce is a rich, syruplike sauce that is used in Chinese cuisine. It is made from oyster extract, but despite the name, it doesn’t taste like fish at all. Oyster sauce tastes like a combination of soy sauce and barbecue sauce. It is both salty and sweet; the salt comes from the brininess of the oysters while the sweet is complex, with hints of caramel. It is less salty than soy sauce and full of umami.
Oyster sauce is normally sold in bottles, but it is sometimes packaged in cans. Popular brands in the US are Hop Sing Lung and Lee Kum Kee. It may be found in the Asian section of the international food aisle of the supermarket, as well as Asian groceries and online. Oyster sauce brands will range in price; read the ingredient list of the cheaper brands as they may contain MSG and caramel coloring. Lower quality sauces will also have a fishy taste.
The vegetarian brands, such as Lee Kum Kee, uses mushrooms as a substitute for the oysters. So there is a true vegetarian Oyster sauce.
Unopened, oyster sauce can be stored in the pantry for one year, but once opened, bottled oyster sauce must be refrigerated, where it will last six months.
Did you know that oyster sauce was invented accidentally by Lee Kum Sheung in 1888. He ran a tea stall that sold cooked oysters. One day, Lee was cooking oysters as usual, but he lost track of time and left them to simmer until he smelled a strong aroma. Lifting the lid of the pot, he was delighted to find the normally clear oyster soup had turned into a thick, brownish sauce with an astonishingly delicious taste. Soon he started selling his newly invented seasoning, which turned out to be a hit with the locals.
Info found on Wikipedia
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