Water-Powered Fish Evisceration System (FES)
Development of a high-speed and high-yield water-powered fish evisceration system (FES) to efficiently pre-process little fish and bycatch for generating minced fish meat is clarified. The system’s idea is currently propelling fish in a flow of water of cutting brushes and blades through an arrangement.
Eviscerated fish are separated from the viscera and water flow in a double screen rotary sieve. The fish evisceration system processed head at the speed of 300 fish, weighing 170-500 gram, off fish/ min when combined with a machine that is heading. Yields of mince produced from walleye pollock, Theragra chalcogramma; and Pacific whiting, Merluccius products; processed from the fish evisceration system ranged between 43 percent and 58%. The yield of muscle from fish was 52%, and the return of tissue from fish was 58%.
Evaluation results suggested that surimi made from minced meat recovered from fish processed using the fish evisceration system was comparable in quality to commercial grade surimi from traditional methods. Redesigned for commercial operation in the Faeroe Islands (Denmark), the system efficiently processed North Atlantic blue whiting,
Micromeritics potassium, with a mean weight of 110 g in a continuous rate of 500-600 fish/min, making deboned mince feeding a surimi processing line at a speed of 2.0 t/h. Yields of mince ranged from round fish from 55 percent to 63 percent. Surimi made in the whiting mincemeat was similar to surimi produced by Norway and France from whiting and marketed into markets.
Magnuson-Stevens Fishery Conservation and Management Act
1996 authorised Magnuson-Stevens Fishery Conservation and Management Act (PL 94-265) defines bycatch as fish harvested in a fishery that isn’t sold or kept for private use and contains economic and regulatory discards. Commercial discards are targeted fish which aren’t retained since they’re undersized, the wrong gender, or of poor quality (Benaka and Dobrzynski, 2004).
Consideration of economic discards is significant since they represent that part of the targeted catch which is unused or is underutilised, and they lead to a financial loss to the fisheries, though still contributing to the total allowable catch. Alverson et al.
1994) estimated that discards from the midwater trawl fishery for walleye pollock, Theragra chalcogramma, in the Bering Sea Aleutian Islands (BSAI) and the Gulf of Alaska to be approximately 6 percent of the landed weight of roughly 1.05 million t (Northwest Fisheries Science Centre in Seattle, 1994).
Regulations were issued in 1997 requiring that by 1998 all chips at sea in the Bering Sea Aleutian Islands keep all Pacific cod, Gadus macrocephalus, and pollock bycatch and by 2003 all rock sole, Lepidopsetta bilineata; and yellowfin sole, Limanda aspera (North Pacific Fishery Management Council, 1998).
An improved retention and usage program had already been accepted as part of the Fisheries Management Program in 1996, addressing the more significant issue of about 273,000 t/yr of groundfish discards in the Bering Sea Aleutian Islands fisheries, with the majority of the discards classed as economic discards (North Pacific Fishery Management Council,1998). Before these regulations bycatch of species that was led could be lost if not feasible.
The commercial fishery for Pacific whiting, Merluccius goods, on the U.S. Pacific shore, lands about 200,000 t/yr (Northwest Fisheries Science Centre in Seattle, 2007). About 70 percent of this catch is harvested and processed at sea, and the rest treated by shore-based surgeries (Northwest Fisheries Science Centre in Seattle, 1996, 1999). An estimated 1,800 t of hake were lost from this fishery in 2005.
As in the pollock fishery processing equipment is used to process the fish. Filleting machines, explicitly designed to handle round fish, such as pollock, whiting and cod, are often calibrated to be site-specific and will perform optimally when fish are of uniform size (Northwest Fisheries Science Centre in Seattle, 1988). As they lead to a better yield per effort using processing technology generally, fish are chosen for filleting.
By way of instance, Whiting of a mean length of 41 cm will yield approximately 30 percent of body weight in off skin, bone outside fillet meat whereas, a 47-cm fish will generate roughly 40 percent (Northwest Fisheries Science Centre in Seattle, 1988). Similar results are expected for cod and pollock. At a 1998 Northwest Fisheries Science Centre in Seattle observer sampling of pollock landings on at-sea-processing vessels, roughly 10 percent of the fish sampled were 38 cm or less in length (Berger (2)). About 1.1 million t of pollock were landed in 1998 (Northwest Fisheries Science Centre in Seattle, 1999). Similarly, it’s estimated that about 13 percent of the Pacific coast whiting landings are composed of <38 cm fish (Dorn (3)).
Also, Bycatch of food fish is chosen for reduction that may be used for human food if processing economics could be improved for the retrieval of muscle that is edible from these fish. We initiated studies to develop a system designed to recover meat from bycatch and fish like Pacific cod, whiting, and Pollock.
Volume throughput is the Limiting factor for the production of fish meat from many fish. Volume is limited by the conveying style of fish processing machines that uses fish to move. The process uses fish to be entrained by a flow of water and run them through evisceration and cutting modules. The quantity of fish is raised to levels that were viable by removing all conveying components.
New Concept for the Processing of Fish
This is an entirely new concept For the processing of fish. Studies had to start with the design, selection of components, assembly, and testing of this system’s essential elements. The basic idea of this procedure is “shooting” fish down a pipe at a flow of water. The target ratio of water to fish was 17 parts waters to fish wt / wt that is one-part. Fixtures from the pipe orient the fish and through an arrangement of cleaning brushes and cutting blades.
In a flow rate of 2,000 L/min, The fish were accelerated to a speed of 8.7 m/s from the 7-cm diameter cutting section to ease passage through the cutting knives. The cut fish passed through segments with inward bristles that removed tissue like parts and viscera of the head.
The flow of water Viscera and the fish leave the pipe into a sieve that divides and material that is secondary and the fish. The liquid containing gill bits, eyes, viscera, and other non-edible parts of the fish pass through the drop and the sieve outward. This display eliminates the recovers and offal water for recycling into the discharge and the machine.
For a few fish species under 300 G, it’s not necessary to remove the heads to generate good mincemeat. This permits a higher volume of fish to be processed. Flesh quality minces for fish over 300 gram, and fish with heads or discolouration at the mind cutting off the head before the plate. Figure 1 is a side view showing a fish flowing in a pipe. Is a view along the axis of the circular tube demonstrating a cross-section of the fish and the six knives for cutting the fish?
A Cornell 8NHPP pump (Cornell Pump, Portland, Oreg.) was used in this study. The pump comes with an 8-in Diameter release and suction and is capable of flows up to 5,000 L/min. The Pump is used to transport and, vegetables, fruit, fish Other food products with minimal damage.
A customised aluminium feed tank sends water and fish through a section of pipe into the pump. The tank has an overflow trough that pipes and captures used water to release. Makeup water is added to maintain water quality. Water is returned in the inkjet sieve to the feed tank. Hand or conveyor pours into the tank fish for evisceration. No fish orientation is needed, eliminating the need.
Fish and Water discharged from the pump pass through a custom stainless-steel reducer that divides blood from 20 cm to 10 cm feeding in the leading section comprising the knives. Reducing the diameter of the pipe into the part that is cutting accelerates flow and gives the energy that drives the fish. Are put inward along the path to the depth.
The role of the very section is to slit the fish lengthwise along six lines. A minimum of 2 knives cavity cuts opens the belly to expose and eliminate the viscera. For removal, the skull divides for little fish that was head-on. Through deboning, cuts through the muscle and skin of the fish expose more surface area for the healing of muscle.
After splitting, the fish enter a section of pipe with bristles and brushes. Viscera and soft tissue at the gut cavity are loosened and removed since the fish pass through this segment. A cm hose included the split and eviscerated fish and water out of sections and the cutting to a separation sieve. Recuperate waste and viscera A rotary sieve can be used to separate fish, and catch water that was sieved for recycling or discharge.
The coarse internal drum includes a cylinder of parallel bars with 1-3 cm openings to different eviscerated fish from the water flow and discharges them into the processing line feeding deboning equipment. The viscera and water flow to pass to the outer drum using a display where waste and viscera are recorded and delivered to the flow that is offal. Water recycled into the pump feed tank or discharged and is captured in a collection pan. The outer display is continuously cleaned by A capacity spray bar. The spray water refreshes the water to restrict build-up in the fish in the concentration of blood.
Pilot Production Measurements
For pilot manufacturing tests, from 1 to 4 t of fish were used. Fish were weighed in fish bags that hold up to 600 kg on host manufacturing plant scales. L buckets that were tared 20 were used to weigh heads, processed fish, viscera, or recovered mince for return data on host plant product scales.
Fish Head Removal
In tests measuring the efficacy of processing head-off fish, three machines were used. For Pollock, a Baader version 417 (Baader North America, Auburn, Wash.) has been utilised. For the ocean, a pocket belt with mind saw arrangement was used. Both of these machines required one to orient fish. A Baader version 424 combined with an “OTTO” fish feeding machine (Neptune Dynamics Ltd., Richmond, B.C., Can.) Was used to process Pacific whiting.
Mince Meat Recovery
For Pollock, a Baader 699 beef separator with 3-millimeter openings was used. For many Pacific whiting, a Toyo version 405 (Toyo Suisan Kikai Co., Ltd., Osaka, Jpn.) Mm, apertures were used. North Atlantic blue whiting mince, Micromeritics potassium, was recovered using a Sepematic 2000 (Modern pack Hoppe GmbH, Bergisch Gladbach, Ger.) With 3 millimetre openings.
To gauge the return of minced meat out of eviscerated fish, all loose meat has been cleaned from the surfaces of the perforated drum. Meat has been gathered and weighed, and batches of fish were fed into the meat separator for yield calculation.
Surimi is purified muscle produced by washing and straining minced meat to get rid of fat, soluble protein, and connective tissue. Two procedures were used to generate surimi determined by the host’s manufacturing equipment processing plants.
One surimi process, based on traditional Japanese fabrication, was utilised for pollock and ocean-caught Pacific whiting (Lin, 2005). The more recent decanter procedure was used to produce surimi from inshore-caught Pacific whiting as clarified by Babbitt et al. (1993). Surimi quality evaluation was conducted together guidelines by Babbitt and Reppond (1988). The fold test (AFDF (5)) was used for the quick assessment of cooked surimi samples.
Concept Scale-Up and Testing
This is a new concept for the processing of fish. Gear development and pilot studies have been conducted in the Northwest Fisheries Science Centre in Seattle Northwest Fisheries Science Centre in Seattle and industrial fish-processing plants in Alaska, Oregon, and British.
Columbia. In trials, the results could be compared to the operations using fish in the landings.
Economic metrics were the quality of surimi, volume throughput, as well as product return. The data from these studies were used to build a fish evisceration system for North Atlantic whiting’s preparation. Production tests were coordinated with the host facility-based to not interfere with the facility and were limited. Operation of fish evisceration system depended on fishing requirements to supply production for comparison with material of comparable quality.
For the microbiological evaluation of surimi generated from whiting processed from the fish evisceration system in Canada, ready-made 3M Petri movie Products (St. Paul, Minn.) that contain standard methods nourishment and indicators which facilitate colony enumeration were utilised. Both coliform and aerobic counts were created.
Chemical and Physical Properties AVOCA
Measurement of pH, gel strength, moisture, brix, and visual flaws of surimi made from pollock and whiting processed from the fish evisceration system were created based on the surimi industry accepted methods described by Babbitt and Reppond (1988), the AVOCA (1985), and AFDF.
Seattle Northwest Fisheries Science Centre
The first evisceration system was initially constructed at the Northwest Fisheries Science Centre in Seattle Northwest Fisheries Science Centre in Seattle Northwest Fisheries Science Centre in Seattle, Wash., where preliminary tests were made. Batches of 250 that is new–1-00 gram Pacific whiting were processed to establish parameters like knife configurations, flow rate, and brushes that are bristle-style to produce fish. At the completion of the first tests, the prototype system was sent to Kodiak, Alaska, and put up at the Alaska Pacific Seafood’s (APS) processing plant for further testing.
Fish size for walleye pollock is in the gram range. Plants with filleting machines can process pollock under 500 gram, which is sent to reduction. Head elimination was necessary by these fish that was discarded in the fish evisceration system for evisceration. Batch trials using fish which were headed involving the eye and edge of gill plate afforded > 95% fish entirely eviscerated and appropriate for additional processing to minced meat.
Whether fish were appropriate for production 1,000 pollock with a mean weight of 495 gram to determinedestined for reduction, were processed to surimi. Heading removed 34 percent of the fish weight. All fish were eviscerated in 4.5 minutes to get a throughput of 222 fish/min and load of 72 kg/min. Evisceration was satisfactory or complete. Headed and gutted fish represented 59.8 percent of starting round fish weight.
The fish were transferred to the production plant in precisely the identical fashion as plant production to a conveyor feeding. Yield measurements from round fish were 52%. The mince judged to be as good as or better than mince generated for output from the plant and was analysed by the surimi operator for the facility.
The meat drained has been washed, and refined before dehydration at a diameter screw press. At this time the quantity of fish meat that is processed wasn’t large enough to pass through the screw press resulting in a dewatered product that had higher moisture content than surimi. Nonetheless, the fish meat has been moved to the mixing and packaging line where it had been blended with cryroprotectants (sugar, sorbitol, phosphates), extruded into 10 kg cubes, and frozen.
Samples of the suspended fish evisceration system surimi were then evaluated in the Fisheries Industrial Technology Centre of the School of Fisheries and Ocean Science, University of Alaska Fairbanks (FITC), in Kodiak and also by the Alaska Pacific Seafoods quality management staff. Evaluation of the more significant moisture content experimental surimi (nearly 80 percent) made it hard to compare with regular surimi product that would have a moisture content of about 75 percent and correspondingly higher protein content.
High water content affects both stability (stress) and elasticity (strain). 76 that is the value for grade SA surimi was surpassed by the L * colour scores for whiteness. The flaws (bone, skin, impurity) score was seven on a scale of 10 evaluated by the plants quality management section.
Results in Table 1 indicated that under production conditions, it could be anticipated from headed that mince generated and water eviscerated fish could produce surimi with colour and impurity scores comparable to grade surimi. The high moisture content of this test surimi resulted in reduced gel strength (GS) values.
But from previous experience, the gel strength of the surimi will be expected to increase from 400 to 600 points if dewatered to a standard moisture content of 75 percent (Reppond and Babbitt, 1997). This would yield a gel strength of up to 850 points, which is quality. No breaking of a sample, with the test, indicated that the evaluation surimi’s elasticity was great.
A natural industry return metric is the mince weight to surimi product ratio that’s 0.55 to 0.6. According to 52% mince yield (Table 2), a quick estimate of surimi yield from whole fish could be 28.6-31.2%. This is a sizable increase in surimi yield compared to the market average of 20-22 percent (AFDF5).
Results of these trials in Kodiak suggested that the fish evisceration system could produce surimi at yields from pollock of around 500 g. This has the potential to increase value and the use of the fish that is smaller.
Inshore Pacific Whiting Trials
After the conclusion of the trials in Alaska, the fish evisceration system was set up in a surimi production plant (Port Fish Ltd.) at Port Alberni, B.C., Can., Where there had been an active fishery for Pacific whiting which is caught in the inner waters of the Straits of Georgia. These fish are often of excellent quality because of meagre infection rate of Myxosporean parasites familiar to the more abundant ocean-caught Pacific whiting (Kabata and Whitaker, 1985). The fish average less than 300 gram in weight.
300 fish with an average weight of 262 g were pulled from the processing line. A random sample of 70 fish had a mean weight of 223 g after processing the fish throughout the fish evisceration system. This was approximately 85 percent of the start fish weight. Minced meat recovery of 8.5 kg in the 70-fish sample provides an estimated 46.3% mince return from whole fish. The mince was indistinguishable from the mince being generated from the plant as judged by the plant foreman and quality control (QC) personnel. Comparatively flesh return from backbone in butterflyfish at the station was approximately 34%.
After the evaluation on whiting, the size of the fish increased, and water evisceration couldn’t be achieved on a consistent basis. A range of batch runs was conducted using led fish which were cut between the edge of the plate and the back of the eye.
After water evisceration, the fish trunks delivered to deboning represented 61-66 percent of the fish fat that was original. The return of meat on a fish basis ranged from 42 percent to 47%. The yield was influenced by the state of the fish and functioning of the machine that was deboning.
Whiting Surimi Test
In this evaluation, 75.4 percent of the whole fish weight stayed after heading. Evisceration with fish evisceration system reduced beginning round fish fat to 64.2 percent of the start weight. Twenty kilograms of the eviscerated fish were deboned, producing 13.6 kg of minced meat leading to a yield of 43.7 percent from round fish. The 800 kilograms of fish that was conducted and eviscerated were utilised to process into surimi.
The absorption of water not influenced the return of fish meat created by the system. The moisture content of the mince generated from entire fish evisceration system processed fish and led fish evisceration system prepared fish was 84.2 percent and 84.3%, respectively. The moisture content of minced meat produced from the plant using traditional filleting equipment was 84.3%. We reasoned that the yields of meat weren’t due to absorption of water.
The gel strength of the surimi and surimi produced by the plant from the same bunch of fish are shown in Table 3. Gel strength results were reduced for the fish evisceration system surimi that is experimental.
The results might be associated with the handling of the fish. The fish were out of a delivery of 90 t. They were more than 24hrs old when processed by the procedure when processed to create the production sample over and above 34h old. Before going the fish were stored for four h with top ice.
The fish were held with ice for another three h before water evisceration. The fish were caught before being processed at the plant that was surimi. Handling and this time of the fish may have led in the gel that was functional worth of the surimi product that ended. The defect score, however, was quite high.
Estimating the last yield of surimi from around fish with 43.7% mince recovery using a moisture content of 84.3 percent and final moisture content of the surimi in 75%, would lead to a surimi yield of 26.7%. The plant at the time was averaging 19.4% product yield from raw material. The gain in return, based on the above numbers, would be 37.6% with the fish evisceration system.
Microbiological tests in the kind of total aerobic plate counts (Alaska Pacific Seafoods) and total coliform counts were made on surimi products made by water evisceration in this study. These were compared to tests made on product manufactured by the server plant.
Alaska Pacific Seafoods is meant by complete for surimi made from fish evisceration system fish were low, and coliform counts were within count amounts. Alaska Pacific Seafoods for surimi were coliform counts lower and higher.
Pacific Ocean Whiting Trials
The fish evisceration system was set up and operated in a processing plant in Hammond, Oreg. The results of an evaluation to gauge the return of minced meat from fish evisceration system and Toyo filleting machines used in the factory were 44.9 percent and 39.5%, respectively. The mince yield of 44.9 percent from whole fish using fish evisceration system was consistent with results from previous evaluations.
In a follow-up test, 3,300 fish with an average weight of 328 gram were processed. The fish eviscerated and were led in 17 min. The fish were moved into the Toyo 405 deboner and to the procedure that was surimi. The plan was to “label” this fish meat on the last of the average plant production.
A sample of the experimental surimi and normal production surimi produced an hour earlier, were analysed by the plant quality control technicians. The cooking regimen for these examples utilised a 30[degrees]C “suwari” set (Alaska Fisheries Development Foundation (5)) before the last cook at 90[degrees]C. This procedure produces gel strength than the widely used 90[degrees]C cook way of measurement and sample preparation.
The gel strength for its experimental surimi was marginally lower (1,290) compared to the plant generated surimi (1,547). The colour measure for fish evisceration system made surimi exceeded the score, and graded FA surimi grading criteria were lower.
Headed Whiting Trials
This trial used an automatic heading measure. Pacific whiting of predominantly 220-360 gram fish with an average weight of 280 g attained a throughput of 300 fish/min. The yield of the return of mince and trunks was 67 percent of fish and led was 50 percent from fish.
The mince’s quality was judged identical to mince which was being generated by the plant with a Toyo 711 filleting machine with two operators and processing the bunch of fish. The plant produced mince from fish in a yield of 35 percent. Table 2 outlines the minced fish returns from the various fish processing trials created with the fish evisceration system. Commercial Program: North Atlantic Blue Whiting
In 2003 a commercial variant of the fish evisceration system was constructed to process North Atlantic blue whiting (NABW), a little species in the cod family, believed to have great potential for surimi production (Trondsen, 1998). The machine was located in Denmark’s Faeroe Islands in the Viking Fish Protein processing plant situated alongside Havsbrun, a large fish meal producer that provides the island’s Atlantic salmon, Salmo spp., farms.
The seas around the Faeroe Islands have always produced sizeable blue whiting catches of over 400,000 t/yr (Standal, 2006). In the time of the study described here, the vast majority of North Atlantic blue whiting (NABW) landings consisted of 80-160 gram fish with a mean size of approximately 110 g. Fish were delivered by decrease fish trawlers and were held onboard in refrigerated seawater at 2[degrees]C but different from fish bound for supper processing.
In fish bags, the fish were iced at landing before processing. To start processing, the fish were moved to a feed tank that delivered a shaker that oriented the fish head for conveying in the fish evisceration system the fish. A rate of 500-600 fish/min provided approximately 2.0 t of minced fish muscle/h had to operate the surimi line.
For a few test runs, feed rates were attained with fish that was a company. Fish exiting reducer and the pump were accelerated up before cleaning sections and going into the cutting.
Two full cutting and cleaning segments were using a selector valve to direct stream. This enabled the fish flow to be changed into the section that was backup without stopping the flow of fish. Care, blade configurations, or cleaning could be reached on the machine to production without interruption. Installation of cleaning components and cutting to the side can be completed in under 5 min.
During the continuous flow of 3.0-3.5 t of around fish/h, there were few incidents requiring shifting of cutting segments with firm fish. The return of flesh ranged from around fish from 55 to 63 percent and was higher when fish were fresher. The performance of surimi from the fish was the quality of which is shown in Table 6, 30-33 %.
North Atlantic Blue Whiting to Surimi
Quality control was an issue for processing of North Atlantic blue whiting to surimi. Raw fish quality varied. Delivery of fish was not achievable, leading to landings of excellent fish that is mixed. Softening of the fish has been proportional to the age of temperature and the fish of storage.
Protease activity can be controlled with the addition of protease pig plasma which increased gel strength of the surimi than twofold. Control of surimi was because of pigments in the fish heads. Similar colour and textural problems were also reported by Trondsen (1998) in a study to ascertain the market value of surimi made from North Atlantic blue whiting.
The colour problem was eliminated whiting by removing the heads. For North Atlantic blue whiting, it was determined that an automatic heading machine for example “OTTO” would significantly improve excellent overall control. Due to an unexpected and fragile surimi market that developed in the time of the startup, together with production issues, management decided to stop surimi production (Nordby (6)).
High volume and higher yield have demonstrated the capacity of this water evisceration system described in this research to efficiently produce minced fish meat from several species of round fish (walleye pollock, Pacific whiting, and North Atlantic blue whiting). A volume throughput speed of up to 6 t of fish/h has been attained.
The volume provides material for operating a processing plant. To accomplish this amount of fish processing using 200 g fish would require the equivalent of a couple of lines of equipment that is traditional. Operation the cost, and installation space would be restrictive in close quarters.
Increased product yield, with the water evisceration process, would create an estimated 2.88 t of minced fish meat per hour from 6 t of fish in 48% return. In contrast, it would require up to eight and three or four lines machine operators to generate the quantity of fish meat.
The quality of surimi made from minced fish meat produced from pollock and whiting processed from the fish evisceration system in this study ranged from FA (high grade) to KB (low to average quality). The production of surimi from North Atlantic blue whiting with the fish evisceration system was efficient in creating a product that is marketable like the conventionally made whiting surimi product.
North Pacific Fishery Management Council. 1998. Improved utilisation and retention program. Overview of the Bering Sea and Aleutian Islands groundfish fishery management program. N. Pac. Fish. Manage. Council. Newsl., May, Anchorage.
- Estimated 2005 Discard and total catch of selected groundfish species. James Hastie, Fishery Resource and Monitoring Division, Northwest Fisheries Science Centre, 2725 Montlake E. Blvd., Seattle 98112 and Marlene Bellman, Pacific States Marine Fisheries Commission, 205 SE Spokane St., Suite 100, Portland OR 97202. Unpubl. rep., Dec. 2006.
- Berger, J. Resource Ecology and Fisheries Management Division, NOAA, NMFS, AFSC, 7600 Sand Point Way N.E., Seattle, WA 98115. Unpubl. 2001, data.
- Dorn, M. Resource Ecology and Fisheries Management Division, NOAA, NMFS, AFSC, 7600 Sand Point Way N.E., Seattle, WA 98115. Unpubl. 2001, data.
- Mention of trade names or commercial firms doesn’t imply endorsement by the National Marine Fisheries Service, NOAA.
- Alaska Fisheries Development Foundation. Alaska Fisheries Development Foundation. 1987. Surimi. It is American. Project summary 1982-1987. AK, Anchorage.
- Nordby, M. World Protein, 16008 41 St. N.E. Lake Forest Park, WA 98155. Private commun., 2007.
Peter M. Nicklason, a Food Process Engineer, affiliated with the University of Idaho, is from the Resource Enhancement and Utilization Technology Division, Northwest Fisheries Science Centre, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112. Harold Barnett is a study Chemist with the Resource Enhancement and Utilization Technology Division, Northwest Fisheries Science Centre, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112. Jerry K. Babbitt, retired, was a Supervisory Research Chemist with the Resource Enhancement and Utilization Technology Division, Northwest Fisheries Science Centre, National Marine Fisheries Service, NOAA (present address: 1816 Simeonof St., Kodiak, AK 99615).