IsolationandNutritionalAnalysisofKrillProteinConcentrate.docVIP

Isolation and Nutritional Analysis of Krill Protein Concentrate J. Gigliotti, J. Tou, J. Jaczynski This word document was downloaded from the website: /en/, please remain this link information when you reproduce , copy, or use it. a href=/enword documents/a Division of Animal and Nutritional Sciences, West Virginia University, PO Box 6108, Morgantown, WV 26506 JUSTIFICATION: Krill are shrimp-like crustaceans with the largest biomass on Earth. Nutritional analysis shows krill to be a good source of high quality protein and omega-3 fatty acids (ω-3 FAs). Despite its abundance and potential nutritional value, krill has not been widely utilized for human consumption due to the lack of proper technology for protein recovery. OBJECTIVES: The study objectives were to isolate krill protein concentrate (KPC) and to determine the nutritional value and safety of KPC for human consumption. METHODS: KPC was recovered using isoelectric solubilization/precipitation. Whole krill was homogenized in water (1:6 w/v) and the protein solubilized at pH=11.0, followed by removal of impurities (shell, appendages, etc) by centrifugation. The solubilized protein was precipitated at pH=5.50 and de-watered by centrifugation. Freeze-drying of the recovered protein yielded KPC, which was used in isocaloric diets containing either 10% KPC or 10% casein or no protein. Rats, routinely used to determine protein quality in infant formulas, were used to determine KPC digestibility, protein quality, and ability to support growth. RESULTS: Proximate analysis indicated KPC had 77% protein and 8% fat (dry basis). KPC protein quality was high as indicated by the presence of all the essential amino acids required by humans. KPC lipid composition consisted of 32% ω-3 FAs. Growth and feed efficiency was lower (P0.001) in rats fed protein-free diet. Weight gain, feed efficiency and protein efficiency ratio were similar (P0.05) between KPC and casein-fed animals. The safety of KPC was