Mắm Tôm Ninh Cơ is a traditional Vietnamese fermented paste made from small marine shrimp and produced by Nam Định Seafood Processing Joint Stock Company. It is prepared from shrimp caught in the coastal waters around Thịnh Long and sea salt. The raw material is salted and left to ferment naturally in large tanks. During fermentation the shrimp proteins gradually break down and create amino acids responsible for the pronounced umami flavor. The finished product has a thick texture and a grayish to purplish-gray color. Its aroma is strong and characteristic of fermented seafood products. The flavor is intensely salty with pronounced marine richness and a long finish. The producer states that the paste is neither diluted nor separated from its liquid portion during production. It is used to prepare dipping sauces served with tofu, boiled meat, and vegetables or as a seasoning in cooked dishes. Before serving it is often mixed with lime juice, sugar, and chili to soften its saltiness and balance its aroma.