83A-17 |
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S. SATHIVEL, Fishery Industrial Technology Center, Univ. of Alaska, Fairbanks, School of Fisheries & Ocean Sciences, 118 Trident Way, Kodiak, AK 99615-7401, P. J. Bechtel, Subarctic Agricultural Research Unit, USDA-ARS-Pacific West Area, Univ. of Alaska, Fairbanks, 245 O'Neill Bldg., Fairbanks, AK 99775-7220, and K. D. Reppond, Northwest Fisheries Science Center, National Oceanic & Atmospheric Administration, National Marine Fisheries Service Utilization Research Lab., PO Box 1638, Kodiak, AK 99615-1638. Over one million metric tons of Pollock (Theragra chalcogramma) is harvested annually from Alaska waters. The byproduct yield from pollock processing was estimated to be approximately 66%. Many Pollock byproducts from fish filleting processing can be used directly as foods or processed to make food ingredients. Proteins can be extracted from byproducts and separated into water soluble and insoluble fractions. The objectives of this study were to isolate the soluble protein fraction from different Pollock byproducts and evaluate the physicochemical and functional properties of the protein powders. Byproducts used for recovering the soluble protein fraction included Pollock viscera, heads, frames, trimmings, gonads, and livers. The samples were separately minced, and water was added (water:mince=1:1, V/W). The mixtures were heated at 85C for 60 minutes and after centrifugation the soluble protein fractions were recovered and freeze dried. Chemical properties determined were protein, lipid, ash, amino acid and mineral contents and functional properties included fat absorption, emulsifying capacity, water absorption capacity, protein solubility and color. The protein powders prepared from viscera, liver, head, frame, trimming, and gonads, respectively, contained 59.8%, 63.5%, 59.1, 75%, 81.3 and 78.2% protein. The emulsifying stability was 71.2, 77, 72, 72, 89.6, and 52.8% for viscera, liver, head, frame, trimming, and gonads, respectively. Highest (12.8 mL of oil/g protein) and lowest fat absorption (1.5 mL of oil/g protein) was observed for Pollock trimmings and liver, respectively. Water absorption capacity (mL/g) of Pollock head and frame protein powders were different from the other protein powders. All protein powders had desirable essential amino acid profile. There were some differences detected between chemical and functional properties of soluble protein powders from Pollock byproducts. The soluble protein powders from Pollock byproducts could have potential uses as functional food and feed ingredients.
Session 83A, Aquatic Food Products: Byproducts, mince and surimi
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