Oyster sauce salt, should be added to the sauce, since the oysters should provide all the savoury flavour. However, this method is prohibitively expensive. Many modern oyster sauces are thickened with cornstarch, flavoured with oyster essence or extract and darkened with caramel. Vegetarian oyster sauce prepared from mushrooms, often oyster mushrooms or shiitake mushrooms, is also popular and generally lower in price. It may contain more taste enhancers if less mushroom extract is used to reduce costs. Most of the oyster sauces available on the market contain added monosodium glutamate (MSG). In recent years MSG-free varieties can also be found. The taste
Oyster more expensive. The Pacific oyster has been grown in the outflow of mariculture ponds. When fish or prawns are grown in ponds, it takes typically of feed to produce of product (dry-dry basis). The other goes into the pond and after mineralization, provides food for phytoplankton, which in turn feeds the oyster. To prevent spawning, sterile oysters are now cultured by crossbreeding tetraploid and diploid oysters. The resulting triploid oyster cannot propagate, which prevents introduced oysters from spreading into unwanted habitats. In many areas, non-native oysters have been introduced in attempts to prop up failing harvests of native varieties. For