This condiment is extremely common in cuisines throughout Southeast Asia and southern China, where it’s integral in many dishes. At its most basic, it’s made by pounding shrimp and/or krill into a paste, salting the resulting mixture, and then letting it ferment from there. It’s a staple in many curries and sauces, in which it’s often integrally important.
Other than that, there is a huge variety in the characteristics of shrimp paste not just from country to country, but even within a given country from region to region.
One of the areas where shrimp paste can vary the most is in its presentation and moisture content — that is, in some areas, shrimp paste will be a thick, viscous liquid while in other regions it’s sold as a dried brick. Meanwhile, the color can range from pale light pink to deeper red to a strong dark brown.
The other realm in which you’ll find different characteristics is the flavor and aroma. Both based on region and quality, some shrimp pastes will have a much stronger flavor and smell than others; some consider higher quality shrimp paste to have a milder smell, for example.
Uwajimaya carries different versions of shrimp paste in our grocery department, where you can check them out and decide which works best for you.