Before I lived in Southeast Asia, I knew that fish sauce–that fermented, salty essence of the sea–is an indispensable condiment for many of the region’s beautiful dishes. I enjoyed it as a component of foods from all over Asia. I don’t think I fully appreciated the scope of its influence, though, until I traveled the length of Vietnam.
In kitchens and on tables throughout Vietnam, fish sauce is always at the ready, truly omnipresent. It features in basic preparations, is applied as a finish, and is a constant in the dipping sauces served alongside almost every dish in a magnificent cuisine.
The making of a champion
When I visited a nuoc mam factory in the village of Duy Hai, not far from Hoi An, it was a chance to see the small-scale production of the wonderful, pungent brew. The lines of baskets and barrels surely contrasted with the industrial containers of enormous commercial outfits elsewhere. Still, fish sauce is fish sauce, and we had a chance to see how the stuff gets made.
There, the day’s catch of small fish was poured into an enormous vat with salt, where the mixture will ferment for six months before being decanted through a cloth into three-liter jugs. Most of the factory’s storage space is given over to giant wooden barrels, where a higher-quality sauce spends its fermentation time.



If fish sauce had a DOP
The salt layered on for fermenting should be sea salt, and salt flats along the coasts of Vietnam and southern Cambodia help fulfill this purpose. Just as the quality of the first press is important in the processing of extra virgin olive oil, the slush of fermented fish, after straining through a cloth-lined bamboo basket, must be the color of fine lager if the resulting sauce is to be considered first-rate.
The fish sauce can be bottled for use at this point, but top quality sauces spend additional time in wooden barrels. Whatever the fermentation period, a good bottle of nuoc mam should be clear from top to bottom, without any sediment.



The very best nuoc mam?
Nuoc mam is the signature ingredient in Vietnamese cuisine. More than rice, fish sauce differentiates a Vietnamese dish from similar preparations in the culinary traditions of neighboring countries. According to the chefs I’ve met on my travels in Vietnam, the best nuoc mam is made from anchovies, and the finished product should be at least 45% fish. Nuoc mam from the island of Phu Quoc, to the west of the Mekong Delta, is considered by a number of chefs to be the best around.
Imagine my delight when I happened on a bottle of a high-octane (70%) version of the stuff in the neighborhood grocery near my temporary home in Phnom Penh. In no time, travel partner Tom and I were adding it to stir-fries and scrambled eggs, and used it to make a simple Vietnamese-style dressing for leafy green salads and fruit plates.

Anita,
Lovely to read about your Vietnamese adventures! I have a new-found appreciation for fish sauce after reading your post today.
Marla, fish sauce was nothing compared to Cambodian Prahok (fermented fish paste)! Stay tuned.