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Updated: Aug 7, 2026
07:44
Analysis of Fatty Acid Content and Composition in Microalgae
Published on: October 1, 2013
Shellfish: proximate composition, minerals, fatty acids, and sterols
I King1, M T Childs, C Dorsett
1Department of Metabolism, University of Washington, Seattle 98195.
Journal of the American Dietetic Association
|May 1, 1990
Summary
Shellfish nutritional content varies widely by species. Generally, these seafoods are rich in zinc, iron, and beneficial long-chain omega-3 fatty acids, making them valuable dietary additions.
Area of Science:
- Marine Biology
- Nutritional Science
- Food Chemistry
Background:
- Shellfish are a significant food source globally and regionally.
- Understanding the nutritional profile of commonly marketed shellfish is crucial for dietary recommendations.
- Regional variations in nutrient content may exist due to environmental factors.
Purpose of the Study:
- To determine the proximate composition, mineral content, fatty acid profiles, and sterol composition of eight commercially important shellfish species from the Northwest.
- To provide a comprehensive nutritional analysis for these shellfish.
- To assess the variability in nutrient content among different shellfish types.
Main Methods:
- Proximate analysis for moisture and lipids.
- Atomic absorption spectrophotometry for mineral content.
- Gas chromatography for fatty acid and sterol analysis.
- Analysis of eight shellfish species: sea scallops, blue mussels, Dungeness crab, pink shrimp, Pacific oysters, Manila clams, and California squid.
Main Results:
- Lipid content varied significantly, from 0.7% in sea scallops to 3.1% in blue mussels.
- Mineral content was highly variable; Northwest samples generally showed lower levels than reported elsewhere.
- Shellfish are good sources of zinc; oysters, mussels, and clams are also rich in iron.
- Long-chain n-3 polyunsaturated fatty acids predominated (37.6%–54.3%), with sea scallops notably high (>50%).
- Cholesterol was the primary sterol in crustaceans and most mollusks, with California squid showing exceptionally high cholesterol levels.
Conclusions:
- Shellfish exhibit considerable nutritional diversity.
- Despite variations, shellfish are generally nutrient-dense and beneficial for human diets.
- Specific species like Pacific oysters, blue mussels, and Manila clams offer particularly high levels of essential minerals like iron.
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