Abstract: In order to evaluate the nutritional value and breeding development prospects, nutritional components in soft part of Nevertia didyma and Natica vitellus were determined using generic methods. The contents of general nutritional compositions, fatty acids, amino acids and mineral elements were analyzed and its nutrients are evaluated. Results showed that Nevertia didyma and Natica vitellus were nutrient-rich with high protein and low fat. The amino acid composition of soft part consisted of 18 common amino acids including 8 essential amino acids. The protein content calculated in wet samples were 19.34% in Nevertia didyma and 15.55% in Natica vitellus. The ratio between essential amino acids and total amino acids were 33.93% in Nevertia didyma and 36.19% in Natica vitellus. Four delicious amino acids were rich with content up to 40%. The coefficient of amino acids ratio was 51.59 in Nevertia didyma and 45.41 in Natica vitellus. Unsaturated fatty acids were abundant in two kinds of shellfish. EPA + DHA accounted for higher than 60% of total UFA. The highest content of major metal elements was K, followed by Mg while Fe was the highest, followed by Zn. The ratio of copper, iron and zinc were reasonable that the values of Zn and Cu were 3.39 in Nevertia didyma and 5.05 in Natica vitellus, and the value of Zn and Fe were 0.33 in Nevertia didyma 0.80 in Natica vitellus. These results demonstrated Nevertia didyma and Natica vitellus were of higher nutritional value and presented broad breeding prospects and market development potential.

Key words: Nevertia didyma, Natica vitellusi, soft part, nutrient composition