Oyster Sauce Vs. Fish Sauce

The first time I fell into the oyster sauce vs. fish sauce debate was, when I was supposed to cook Thai for dinner. We had invited some friends over for dinner and I had decided on Thai cuisine for the evening. As I was surfing for recipes, I saw that in the ingredient list of some recipes, fish sauce was mentioned, while in others oyster sauce was mentioned. Now if they were about to different dishes, I would not have fallen into the trap, but since for the same recipe, some used oyster sauce and some used fish sauce I was inadvertently drawn into the debate. Although I had a lot of work at hand, I had to get to the root to find out, which of them is better and should be used. Also I realized, when one asks for fish sauce, we end up getting only oyster sauce. So, now, I wanted to know the difference between oyster sauce and fish sauce and also, if I could substitute one for the other, if yes, how.

Difference Between Oyster Sauce and Fish Sauce

The first point that we must understand, when we talk about oyster and fish sauce, is that as the name suggests, oyster is used to make oyster sauce and fish is used to make fish sauce. If they were the same, they would not have two different names. Oyster sauce per se is a recent discovery, as fish sauce has been used since the seventeenth century.

Often, fish sauce is said to be an oyster sauce substitute, however, there is a big difference in the taste of the said sauces. Oyster sauce inherently has a sweeter taste to it. On the other hand, fish sauce has a salty taste. In other words, both the sauces are on either side of the taste spectrum. So, if one has to be substituted for the other, you can understand the change in taste they will bring about.

Now comes the consistency of the said sauces. Oyster sauce is an extract of the oysters, therefore has a thicker consistency and is viscous. Its color is often similar to that of soy sauce, but with much thicker consistency. On the other hand, fish sauce is made by marinating and fermenting the fish in water, therefore, has a watery consistency. It is often clear and amber to look at.

After consistency, comes the odor of the sauces. As compared to the fish sauce, oyster sauce has a milder aroma. It does not have any sort of fishy odor. As a matter of fact, you can sample oyster sauce straight out of the bottle and you will not find it gross. On the other hand, fish sauce has a very typical fish-like odor. If you happen to open the bottle and smell it, you may not get as much a fishy odor. However, the moment you sample it, you will get the fishy odor.

This brings us to the method used for making oyster and fish sauce. To make oyster sauce, oysters are boiled in water to derive the oyster broth. The broth is then thickened over low flame, till the desired consistency is achieved. Once it has been thickened to the desired consistency, it is caramelized. So that the sauce does not go bad, different preservatives and monosodium glutamate may be added. While to make fish sauce, fish is fermented in water for a long duration. In some cases, the fermenting process can last a year, till the fish completely melts in water. It is often left in the sun. The jars are opened at regular intervals. When it is time to remove the sauce, a hole is made at the bottom of the jar, so that the sauce passes through the fish remains, and it is sieved through a cloth. This derived sauce is left out in the open, to reduce the odor and then the sauce is bottled.

Now comes the question in which cuisine is oyster sauce used, and which cuisine uses fish sauce. If one considers authentic Chinese food, you will see that it uses oyster sauce. Like me, if you are a Thai food fan, then oyster sauce is the right choice. In Vietnamese cuisine, the use of fish sauce is preferred.

I hope this write-up has answered your queries regarding oyster and fish sauce and you know the difference between well. It will ensure you use the right sauce for the right cuisine and are able to derive the best flavors from it.