Surimi processors are committed to improve utilization of seafood resources, increase productivity and reduce organic matter discharged into the environment. The object of this study was to recover protein from pollock surimi processing washwater using membrane filtration and characterize properties of the recovered material. A pilot unit equipped with membrane elements concentrated protein from the surimi wash-water. Membrane concentrate and control surimi samples were analyzed for proximate composition, lipid oxidation, color, sodium dodecyl sulfate gel electrophoresis, amino acids and minerals. Membrane concentrate, membrane concentrate plus surimi and control surimi were monitored for 180 days of storage at -20C. The membrane concentrate had significantly higher moisture and lipid, but lower protein content than surimi. As determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis, membrane concentrate proteins displayed a greater amount of lower molar mass molecules compared with surimi. The amino acid profile was comparable to control surimi and the recovered membrane concentrate proteins had similar nutritional values to that of surimi. The results indicate that the addition of 5% membrane concentrate to surimi will not adversely affect the storage at -20C and that the recovered wash-water protein could be used to obtain a fish protein ingredient or added back at a low percentage to surimi products. PRACTICAL APPLICATIONSIn order to increase productivity and improve utilization of seafood resources, surimi processors are looking into alternative technologies to recover proteins and other material from the wastewater. Membrane filtration is a promising option for the concentration of wastewater. This study was conducted to determine the recovery and characterize the material recovered from surimi wash-water using a commercial membrane filtration unit. It was demonstrated that the recoverable material is nutritionally similar to the final surimi product and that the overall yield can be increased using membrane technology. In addition to the benefit of recovering protein, the membrane filtration can reduce the amount of material in the waste stream. Journal of Food Quality ISSN 1745-4557RECOVERY OF PROTEIN FROM SURIMI WASH-WATER J.J. STINE ET AL.

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Unpurified red salmon oil (UPSO) was processed to obtain purified salmon oil (PSO) by chitosan adsorption. Both unpurified and purified oils were evaluated for peroxide value (PV), free fatty acids (FFA), fatty acid methyl esters (FAME), moisture, and color. An emulsion system containing PSO (EPSO) was prepared; the system was analyzed for color, rheological properties and microstructure before spray drying to produce microencapsulated PSO (MPSO). MPSO was analyzed for moisture, water activity, bulk density, color and FAME composition. PSO or MPSO was added to a commercial baby-food product (CB) and all baby-food samples were compared for PV, FFAs, FAME, and color. Experiments were completed in triplicate and data statistically analyzed (a = 0.05). PSO had higher percentages of total omega-3, total monounsaturated DHA, and EPA than MPSO. EPSO exhibited viscoelastic characteristic and the droplet size of EPSO was 1-9 lm. Total omega-3 and total monounsaturated contents of the MPSO were lower than PSO. All baby-food samples with added fish oils had similar color. DHA and EPA contents of baby food were increased over three fold by the addition of PSO and/or MPSO. MPSO can be added to CB resulting in increasing total percent omega-3 fatty acids while maintaining desirable attributes of the CB.

This study investigated the effect of blueberry juice on menhaden oil lipid oxidation during microencapsulation. Oil in water emulsions containing menhaden oil with 0, 5, or 10% blueberry juice were spray dried to produce control-M, 5% BJ-M, and 10% BJ-M microencapsulated powders, respectively. All microencapsulated powders had similar encapsulation efficiencies with low surface oil content. Peroxide value (meq/kg of oil) was 4.50, 4.31, and 3.38 for control-M, 5% BJ-M and 10% BJ-M, respectively. Ten percent BJ-M had lower (P < 0.05) anisidine value, and totox values than 5% BJ-M and control-M. This indicated that 10% blueberry juice reduced lipid oxidation in menhaden oil during microencapsulation to a greater extent than the other formulations.