Scott Smiley

Chemical composition of the giant red sea cucumber, Parastichopus californicus, commercially harvested in Alaska

Giant red sea cucumbers, Parastichopus californicus, are commercially harvested in the U.S. Pacific Northwest; however, the nutritional and chemical properties of its edible muscle bands and body wall have not been fully elucidated. In particular are the fatty acid profiles of P. californicus tissues, which have not been documented. Sea cucumbers were delivered live and muscle bands and body wall freeze dried, vacuum packed, and stored at –30°C until analyzed. Proximate composition of freeze-dried tissues varied greatly with muscle bands being composed of 68% protein, 12% ash, 9% carbohydrate, and 5% lipids, while the body wall was composed of 47% protein, 26% ash, 15% carbohydrate, and 8% lipids. The hydroxyproline, proline, and glycine contents of the body wall were much higher than those in muscle bands, consistent with the larger amount of connective tissue. Calcium, magnesium, sodium, and iron contents were higher in the body wall than those in muscle bands, whereas the opposite was observed for zinc content. Total long-chain n-3 fatty acid contents were 19% and 32% of total fatty acids in body wall and muscle bands, respectively. Muscle bands had higher content of eicosapentaenoic acid (20:5n-3) than body wall at 22.6% and 12.3%, respectively. High content of arachidonic acid (20:4n-6) was recorded in both body wall (7.1%) and muscle bands (9.9%). Overall, the fatty acid profiles of body wall and muscle bands of P. californicus resemble those described for other species; however, the distribution and occurrence of certain fatty acids is unique to P. californicus, being representative of the fatty acid composition of temperate-polar marine organisms. The chemical characterization of freeze-dried edible tissues from P. californicus demonstrated that these products have valuable nutritional properties. The body wall, a food product of lower market value than muscle bands, could be better utilized for nutraceutical and pharmaceutical applications.

Protein digestibility evaluations of meat and fish substrates using laboratory, avian, and ileally cannulated dog assays

Meat and fish serve as important protein sources in the companion animal diet; however, limited protein digestibility data are available for assessing protein digestibility differences among good-quality protein sources. Beef loin, pork loin, chicken breast, pollock fillet, and salmon fillet were evaluated for composition, protein digestibility, and AA bioavailability using the immobilized digestive enzyme assay, cecectomized rooster assay, and ileally cannulated dog assay. Pollock contained the greatest amount of CP, total essential AA (TEAA), and total nonessential AA (TNEAA; DM basis; 96.9, 38.6, and 50.3%, respectively). Salmon contained the next greatest amounts (92.8, 36.4, and 44.6%), followed by chicken (90.3, 36.1, 43.2%). Beef had the least CP content (82.7%), but had slightly greater TEAA and TNEAA concentrations (33.9, 42.0%) compared with pork (86.2, 33.6, 41.3%). Immobilized digestive enzyme assay values were greatest for pollock fillet (0.71) and least for chicken breast (0.52). Beef loin, pork loin, and salmon fillet were similar (0.63, 0.62, and 0.64, respectively). Standardized TEAA and TNEAA digestibility coefficients, evaluated using the cecectomized rooster assay, were greatest (P < 0.05) for pollock fillet (90.4 and 89.8%, respectively) and least (P < 0.05) for chicken breast (86.6 and 85.9%, respectively) and salmon fillet (87.8 and 86.4%, respectively). Dogs assigned to a 5 x 5 Latin square design were fed 5 diets, with each test substrate as the major protein source. No significant differences (P > 0.05) were found in ileal digestibility of protein. Values ranged from 88.9% for chicken to 90.5% for pork loin and pollock fillet. Ileal TEAA and TNEAA coefficients were not different among test substrates, with values between 91.7 and 92.7%, and 88.8 and 90.4%, respectively. Total tract CP apparent digestibility values ranged from 94.4 to 94.8%, with no differences noted among treatments. Despite marked differences in composition and predicted and standardized digestibility values, when the protein sources were added to diets at a concentration of approximately 30% (25% of total energy intake), no differences in test protein substrates were noted in either ileal or total tract nutrient digestibility.

Chemical Characterization of Testes Meals Made from Alaska's Seafood Processing Byproducts

ABSTRACT Our objective was to produce a unique feed ingredient from underutilized walleye pollock (Theragra chalcogramma) and pink salmon (Oncorhynchus gorbuscha) testes. Protein content in meals from both species (72% and 80%, respectively) were above the values found in high quality herring meals (∼70%), but both were poor in some essential amino acids, e.g., methionine. Additionally, both were good sources of the amino acid taurine (1.7 and 2.2% of meal, respectively). Pollock meal was very rich in phospholipids (82% of total lipids) and in DHA (28 mg/g meal) and EPA (18 mg/g meal), indicating potential as an ingredient in larval starter diets. The purine contents in both pollock and salmon testes meals were more than 10 times the concentrations found in other fish byproducts or commercial fishmeals. The high concentrations of purines found in these testes, especially in the salmon meal, make it an ideal candidate for an immune system stimulant when added to dietary formulations.

Nutritional Quality of Fish Meals Made from By-Products of the Alaska Fishing Industry in Diets for Pacific White Shrimp (Litopenaeus vannamei)

Abstract The nutritional quality of ten commercially available white fish meals made from by-products of the Alaska fish processing industry (primarily pollock) was determined. Pelleted feeds were manufactured containing these meals in complete replacement of a low-temperature processed Norwegian fish meal (control). These feeds were fed to triplicate tanks of Pacific white shrimp at the facilities of the Oceanic Institute for a period of ten weeks. At the end of the trial, the growth, feed conversion ratio and survival data were subjected to analysis of variance procedures. The final weight of the shrimp was more than ten times the initial and mean survival was 97%. There were no significant differences in performance parameters among the treatments. It is concluded that the nutritional quality of Alaska white fish meals is equivalent to the highest standard in the industry and are of suitable quality for inclusion in commercial shrimp feeds.

Quality Characteristics of Freeze-Dried Salmon Baby Food Purees During Storage

Five combinations of baby food (puree; puree + pink salmon roe; puree + bone; puree + salmon oil; puree + oil + bone) were formulated from retort-processed sockeye (red) salmon puree base, freeze-dried; then evaluated for color, odor, ability to rehydrate, and storage stability. Baby food was retort-processed, freeze-dried, vacuum-packaged, then stored at 22°C for 4 months. Rehydration was best for the puree only (71.7%), about 53% for puree + roe and puree + oil, and about 48.5% for that containing puree + oil + bone. Adding roe to freeze-dried salmon baby food puree increased fishy, rancid, metallic, and sweaty odor; and lightened and decreased redness, yellowness, and visual color intensity. Adding salmon oil increased salmon odor slightly, yellowness, and visual color intensity and decreased color saturation during storage. Adding salmon bone decreased salmon odor and true red color and increased rancid and buttery odor intensities, yellowness, and visual color intensity. Increasing hue angle indicates that the product is becoming less red. Adding salmon oil and bone together increased salmon, fishy, rancid, and sweaty odor intensities and reduced true red color and visual color intensity. Retort-processed, freeze-dried salmon baby food puree with no added roe, oil, and/or bone had and retained the most intense red color throughout the storage period. These data suggest that salmon puree alone consistently produced the highest quality retort-processed, freeze-dried product.