1nternational By-Products Conference 127 April 1990, Anchorage, Alaska

QUALITY MEAL: SPECIFICATIONS AND USE IN AND FUR FARMING

Nils Chr. Jensen Esbjerg Fiskeindustri Esbjerg, Denmark

INTRODUCTION Table 1. Percent composition of fish meal.

Esbjerg Fiskeindustri was founded in 1989 through Average Minimum Maximum a merger of Andelssild and Vestjysk Fiskemelsfabrik, and is owned by the suppliers. More than 130 Protein 728 68 74 vessels ensure an annual supply of about 750,000 Oil 5 10 metric tons of fresh raw materials. The daily produc- Ash 11 18 tion capacity is 7,000 metric tons of raw materials Water 147 2 4 1 103 and the production is carried out in four independent Salt process sections. Esbjerg Fiskeindustri is the world' s largest single producer of quality fish meal and and handles half the total Danish production of fish meal and oil. The products are marketed under the rials and contributesto the landing of top quality fish. trademark 999. For the fishermen, there may be an economic gain of up The raw material consists of small fish normally not to 50% by landing fresh fish. Fresh fish is a must when used for human consumption, such as sand eel producing quality fish meal for aquacultureand fur Ammodytes sp.!, Norway pout Trisopterus esmarki! farming. and Sprauus sprauus!. During the sand eel sea- The. raw materials are processed by boiling, son, from April to July, 70% of the annual catch is pressing, separation, evaporation, and drying. The landed. processinggenerates about 22% fish meal and 6% fish oil. During all key stagesof the production, quality PRODUCTION OF FISH MEAL AND FISH OIL is controlled and samples are drawn for laboratory tests. Analyses on final products are also performed. Immediately after catching, the fish is cooled by The composition of fish meal depends on the raw measured quantities of ice, which ensures that the raw material;a generalcomposition of fish mealis shownin materials are absolutely fresh when landed. Table 1. Fish meal protein contains all the essential Before landing, reports are submitted concerning amino acids. The fish meal has a high content of lysine, the nature and freshness of the catches. On this basis the methionine, and cysteine, and a high digestibility and factory evaluateswhich product can be madefrom the biological value, which makesit a well suited ingredi- raw materials and which process section is best suited. ent in diets. The oil in the fish meal is protected When the ship arrives, efficient suction equipment en- against oxidation by 150 ppm ethoxyquin. suresprompt unloading,and the fish arethen passed on The Danish Association of Fish Meal and Fish Oil for direct processing. Manufacturershas sponsored several experiments at the Representative samples are drawn from each cargo National Institute of Animal Science and the Danish and analyzedfor freshnessof raw material, expressed Trout Culture Research Station to develop new products. by the TVN value total volatile nitrogen! in milligrams The research involves different process condi- nitrogen per 100grams of fish. A low TVN indicates tions, mixed feeds. and different species of animals fresh fish. The pricing system rewards fresh raw mate- ruminants, mink, piglets, and trout!. The experiments have proved that there can be a greatdifference in the Author's address: Esbjerg Fiskeindustri, Fiskerihavnsgade feed utilization and daily gain response depending on 35, Postboks 1049, DK-6700, Esbjerg, Denmark. the quality of the raw materialused for the productionof 128 Market Specifications

Table 2. Feed evaluation of different fish meals.

Drying TVN in High feed intake Low feed intake WG% method raw fish BVa WG% BVa 1. 17 Indirect steam drier 30 0.49 1.42 0.50 130 0.46 1.42 0.46 1.05 1.07 Freeze drier 30 0.52 1.45 0.51 130 0.45 1.34 0.42 1.1 1

Roller drier 30 0.56 1.46 0.53 1.06 130 0.46 1.28 0.44 1. 14 TVN = Totalvolatile nitrogen. BVa = Biologicalvalue. WG = Dailyweight gain.

fish meal Danish Association 1983!. The overall con- Fiskeindustri in collaboration with Atlas Industries and clusionis thatfish mealproduced from freshraw material the Danish Trout Culture Research Station have done is a highly nutritional product. someexperiments Fosbiil 198S,Jensen 1986!. In the tests, various methods of drying were com- paredand the feedvalue of the fish mealswas deter- THE INFLUENCE OF RAW minedby growthexperiments with rainbowtrouts in MATERIAL QUALITY AND PROCESS aquariaat 12'C. Thepilot plantdrying methods com- ON THE FEED VALUE prisednormal industrial indirect steam drying, freeze drying, vacuumdrying, hot-air drying, and roller To provethe effect of raw materialquality on fish drying. meal feed value for trout, the Danish Trout Culture The experimentsshow that gentle drying doesnot Research Station carried out a series of tests in col- producequality improvements over drying performed laborationwith the TechnologicalLaboratory, Ministry in a steam heated disc-drier operated under normal of unpublished data!. conditions. In four repeatedexperiments with different raw The quality of the raw materialis probablythe materials,fish wholemeal and presscake meal produced mostimportant parameter. It hasthe greatest influence in a pilot plant werecompared in feedingtests with on the fish meal quality, particularly when good pro- rainbow trout Salmogai rdneri Richardson,1836!. The ductionpractice is established.Some of theresults are fish meals were produced from fresh raw materials shown in Table 2. Details from the experiments are TVN less than 50 mg N per 100 g! and stale raw presentedin Jensen1986.! material TVN greaterthan 1SOmg N per 100 g!. The Theexperiments were planned as factorial experi- stale raw material was from the same batch of fish as the ments with the following factors: fresh, but stored for some days at ambient temperature. The same conclusion can be drawn from the four Qualitv >ift awmaterial. Two levels: TVN 30mg N per tests. The bestdaily gain responseis obtainedwith fish 100 g and 130mg N per 100 g. whole meal produced1'rom fresh raw materials,fol- Dryingmethod. Three levels: Indirect steam heated disc lowed by presscakemeal from fresh fish, presscake drier conventional process!, freeze drier low meal from stale raw material, and whole meal from temperatureprocess!, and roller drier high tem- stale raw material. perature-shorttime process!. The difference between the presscakemeals is Feed intake. Two levels: High .45 g protein and minor comparedwith the difference betweenthe 0.21g oil perday per 100g trout!,and low .45 g whole meals. The solubles from fresh fish contain a lot proteinand 0.13 g oil perday per 100g trout!. of nutrients, whereas the solubles from stale fish con- tain water-solubletoxic compounds.This explainsthe The raw material with TVN 30 was fresh, and the difference between the whole meals and why the raw material with TVN 130 was deteriorated but was presscakemeal from stalefish is betterthan the whole not putrid. The feedinglevels were low to showdif- meal from stale fish. ferences if any! in the feed utilization. The feed was To prove the effect of' gentle drying and quality of produced as moist pellets and consists of fish meal, raw material on fish meal quality for trout, Esbjerg fish oil, starch, blood meal, whey, lecithin, alginate, International By-ProductsConference 129

Table 3. True digestibilityof fish meal to mink. Table 4. Compositionof dry pelletsfor trout.

Drying Carbo- Metabolizable temperature TVN mg N/100g in raw material Protein Fat hydrate energy 'C 22 S3 93 kcal/kg

60 94.5 94.3 93.7 19SO-1960 35 5 30 2 200 95 94.8 94.0 93.8 1960 1970 40 7 23 2,500 140 93.0 91.7 88.9 1970-1980 53 11 12 3,100 1980 1987 50 20 10 3,800 1987 42 24 19 4,300 vitamin mix, and water. Thefeed evaluation including the apparent biologi- cal value BVa! and the daily weight gain WG %! is Table. 5. Compositionof wet mink feed. shown in Table 2. There are no practical differences related to the drying methodsin the utilization of the Fish offal 50% 60+/o experimentaldiets based on fish mealproduced from the Fish silage 5 lo 10% same raw material. This means that gentle drying does Industrial fish 0% 10% not produce quality improvements over drying per- Poultry offal S% 10+/o formed in a steam heated disc-drier operated under Fish meal 0% 6% normal conditions. Vitamin mix The quality of the raw materialhad an influenceon Barley 5% utilization; the value of the diet decreased with increas- Metabolizable energy 1,000 kcal/kg ing deteriorationof the raw material. Gulbrandsenand Hjertnes986! havecarried out similar testswith mink. They testedthe truedigestibility of fish meal to mink as a function of drying temperature needfor a highly digestible fish meal with a low phos- andraw materialquality. They concludedthat fish meal phorus content. temperaturesof over 100'C during drying reducesthe ln Denmarkthe compositionof dry pelletsfor trout qualityof the fish meal seeTable 3!. Thereis alsoa haschanged during the last yearsto reducethe pollution slight decreasein true digestibility with increasing problems: The energy content has increasedbecause TVN in the raw material. the protein level i» lower and the fat content is higher Pike et al. 990! refer to other Norwegianexperi- Table 4! Alsted 1990!. The latest types of feed are mentswith temperatureexposure of fish meal and true producedby extrusion. protein digestibility in adult male mink, with the same The dry pellets are basedon fish meal and fish oil conclusion:fish meal temperaturesof over 100'C dur- and the demand for highly digestible protein fish ing drying reducestrue digestibility. meal! increaseswith decreasedprotein level in the dry A common conclusion concerning fish meal for pellets. aquacultureand fur farming can be drawn: The best productsare obtained with fish wholemeal produced FISH MEAL FOR FUR FARMING from fresh raw materials that have been processed under conditions where the temperature in the product In Denmarkthere are two types of feed for minks: have been below 100'C. wet feed, basedon fish offal and whole fresh industrial I'ish; and dry pellets basedon fish meal. The wet feed alsocontains up to 6% fish meal seeTable 5!, while the FISH MEAL FOR AQUACULTURE dry pelletscontain up to S0%fish meal.The composi- Production of fish in aquaculture is increasing tion of the dry pellets is 30% 45% protein, 15% 2S% worldwide with an increasingdemand for quality fish fat, and 3,000 3,8SOkilocalories per kilogram metabo- meal. lizable energy. Environmental problems causedby nitrogen and The Danish mink feed producersprefer presscake phosphorusfrom will in the future put meal both for wet feed and dry pellets,to guaranteethe demands to the fish farmers and feed producers to feed value. They know they never will get the best minimize this pollution. At that time there will be a fish meal a whole meal produced from fresh fish, 130 Ma>ket Specifications

Table 6. Percentcomposition of differenttypes of Gulbrandsen,K.E. andT.Hjertnes. 1986. Proteinkvalitet 999 fish meal. i sildemeltil pelsdyr. NJF MeetingFinland Nordic Agriculture Association!. September1986, 6 pp. Standard Presscake Whole meal Jensen. N.C. 1986. Evaluation of the influence of fish meal meal aquaculture drying methodson the feed value of fish meal for rainbow trout. International Association of Fish Protein 71.4 74.1 72.2 Meal Manufacturers. Rec. of Ann. Conf. 1986, pp. Fat 8.0 6.5 8.2 74-86. Moisture 6.4 6.1 9.5 Salt 2.8 0.9 1.0 Pike, I.H., G. Andorsdottir, and H. Mundheim. 1990. FFA of oil* 21 ]2 The role of fish meal in diets for salmonids. Inter- Ly sine 5.0 125.8 S.8 national Association of Fish Meal Manufacturers. Methionine Technical Bulletin no. 24, p. 14. and cysteinc 2.2 3.0 2.9

*Free fatty acids. QUESTIONS AND ANSWERS What does your specification of multi-enzyme at 88% refer to'? This is a three enzymemix. You can compareit which is preferred by the mink feed producers in with TORRY-pepsin. The Danish regulation re- Finland. quires that chemical analysis. With a very fine ground fish meal, your enzyme digestibility will FISH MEAL SPECIFICATIONS increaseand you have to be very specific about An exampleof the compositionof a standardfish chemical analysis. meal,a presscakemeal, and a wholemeal recommended Are medications added to fish meal or fish oil, and for aquacultureand mink feedis shownin Table 6. The if so, what kinds and how much? content of selected amino acid» in standard fish meal No, we don't add medication. produced from unspecilied raw materials is lower There's no disease problem with it'? than in the presscakemeal and the aquaculturemeal producedfrom fresh raw material». A. It's a problemin theindustry, especially in Denmark. The raw materials that Esbjerg Fiskeindustri uses In Denmark most of the farming is fresh water trout. for production of fish whole meal for aquacultureand And of course there are diseases. When you take fur farming havean averagemaximum TVN of 60 mg N these trout to seawater, 99% run into disease, but per 100g, and no fish hasTVN over 80mg N per 100g. you can cure them. The digestibility of whole meal is greater than press- Thi» morning we heardthat you get the bestquality cake meal. whenyou havewarm temperature in the drier aslow In conclusion,quality fish meal ideal for aquacul- as 70. Now you say up to 95 you still have good ture and fur farming can be specified as whole meal product. Who is right and who is wrong? made of fresh raw material produced under mild A. I would sayour trial andthe Norwegians' trial with conditions. mink digestibility showthe sameresults. Whenthe Norwegianscompare the LT 94, the Norse mink, REFERENCF.S you can see a difference but you also have two quality differences, such as the LT meal is pro- Alsted, N.S. 1990. Dansk grredfoder. Personal duced from fish with TVN below 50. The Norse communication. mink is produced with TVN below 90. So two Danish Association of Fish Meal and Fish Oil Manu- parameterschange, both the raw material quality facturers. 1983. Quality criteria for fish meal. andthe temperature. The quality of the raw material March 1983, 222 pp. is the most important factor. Secondis how you Fosbiil P. 1985. The effect of careful drying and processit. Of course,if you aren't right you destroy processingon the quality of fish meal. International the protein. But as long as you have water in your Association of Fish Meal Manufacturers. Rec. of product, and evaporatewater, you don't exceed Ann. Conf. 1985, pp. 28 57. those temperatures. InternationalBy-Products Conference l3l April l990, Anchorage,Alaska

NEW PRODUCTS,PROCESSING POSSIBILITIES, AND MARKETS FOR FISH OIL

Baldur Hjaltason Lysi Hf Reykjavik, Iceland

Althoughfish oil hasbeen used as a fuelin some has developedslowly. During the last decadeswe partsof the world for centuriesand has been commer- have also seenimmense changes in the world oil and ciallyavailable since the beginning of thecentury for fat productionwhere both soya oil andlately palm oil industrialpurposes, it was only 50 yearsago that it productionhas increased considerably. Today fish oil becamea commercialsource for humanconsumption. accountsfor only 2% of the total world marketfor When we refer to fish oil we usually mean oil edible fats and oils. Although a numberof countries producedfrom fatty pelagic fish. Today fish oil isa by- producefish oil, thereare only sevenmajor producers: productof the fish mealindustry. In production,the Chile,Denmark, Iceland, Norway, Peru, the USA, and main emphasisis on fish meal, which is still more Japan.Japan is thelargest single producer of fishoil valuable and more in demand than fish oil. Figure 1!. Fish liver oil, on the other hand, is producedonly Commercial fish oil is usually composedof over from the liver of the fish. In somecases it hastherapeutic 90%triglycerides, each usually containing three dif- valueand is an importantsource of vitaminsA andD. ferentfatty acids.An additional8% consists of mono- Documentationfrom 1657 indicatesthat and diglyceridesand other lipids such as phospho- washelpful againstnight-blindness, and in 1770Dr. lipids. Theunsaponifiable portion that accounts for SamuelKay, a physicianat ManchesterInfirmary in an additional 1.S%to 2.0% consistsprincipally of ste- England,gave a lectureon his studies of howcod liver rols,glyceryl ethers, hydrocarbons, and fatty alcohols, oil helpedagainst rheumatism. In 1920it wasdiscov- alongwith the fat-soluble vitamins A, D, andE. The ered that cod liver contained vitamins A and D residuecontains other componentsin small quantities. Anonymous1984!. After the Japanesestarted pro- Fish liver oil has the samecharacteristics, but usually ductionof syntheticvitamin D, cod liver oil lost its contains more unsaturatedfatty acids and a higher identityand did not recoveruntil 1979when the dis- amountof the vitamins sincethe liver actsas a vitamin cussion of the health benefits of omega-3fatty acids reservoir for fish. What makes fish oil different from other oils is began. Becauseof its physicalcharacteristics, fish oil was mainlythe uniquevariety of fatty acidsit contains at first mainlyused for industrialpurposes, such as in TableI!. Anotherfactor is thehigh degree of unsatu- the leatherindustry, for making soaps,and in the manu- ratedfatty acids. The amountand variety of the fatty factureof paints. As processingtechnology became acidsin fish oil variesfrom one fish speciesto another, moresophisticated, a newpossibility emerged for the and also with the seasonof the year, fish diet, fishing food manufacturers to use fish oil in shortenings location,ocean temperature, nutritional and spawning margarine,and fats for the bakingand confectionery state,etc. Only eightto tenfatty acidsmake up 8S% industry.Margarine was invented in 1869because of 90% of the total. Also of interest is that fish oil con- the shortageof butter in Europe. In the beginning tainsa highamount of fatty acidswith thefirst double renderedbeef fat was used,but in the early 1900safter bondbetween the third andfourth carbonatom, counted the hydrogenationprocess was developed to produce from the terminalmethyl group. This family of fatty hardenedfat from liquid oil», a hugenew markedfor acids is called the omega-3 fatty acids and is found fish oil opened. Sincethen the marketfor fish oil primarilyin oil of marineorigin. In contrast,vegetable oils containmainly unsaturatedfatty acidsfrom the omega-6family and animalfat from the omega-9 Author'saddress: Lysi Hf, Grandavegur42, P.O.Box 625, family. Huntanmetabolism differcntiatcs between 121 Reykjavik, Iceland. the positionof the first doublebond, i.e., omega-3, 132 Market Specifi'cations

~ 1984 RHIEM 1985 ~ 1986

Peru

Chile

USA

Japan

Iceland

Norway

Denmark

50 100 150 200 250 300 350 400 450 500

Thousands of Metric Tons

Figure 1. Fish oil production in seven majo> fish-producing countries, 1984 1986.

omega-6, or omega-9. 1987!. Results now indicate that consumption of As far back as 1956, data were published showing omega-3 fatty acids can help people suffering from that intake of fish oil had a cholesterol-lowering effect arthritis, asthma, and certain types of cancer. Research for humans. This was the first indication that fish oil is also being conducted on the role played by omega-3 and fish diet guard against coronary diseases Nelson fatty acids in the central nervous system and in growth 1972!. In 1972 Dyerberg and co-workers published and development Simopoulos 1986, Horisberger and findings that the low incidence of coronary heart disease Bracco 1987!. in Greenland was related to their diet, and especially The Second International Conference on the Health to their high intake of the eicosapentaenoic polyunsatu- Effects of Omega-3 Polyunsaturated Fatty Acids in rated fatty acid EPA! of the omega-3 family Bang , held in Washington, D.C., March 1990, con- and Dyerberg 1972, Dyerberg et al. 1978!. Only then cluded that all human diets should include omega-3 did the scientific community become aware of the health- fatty acids, and a concern was expressed that steps related roles of the omega-3 fatty acids. At first, re- should be taken to stop marketing enteral and parenteral searchersstudied the hypo 1 ipidaemicand anti-thrombotic formulas that fail to include any omega-3 fatty acids. effects of EPA, but after the discovery of prostaglan- Furthermore, new evidence with an extremely high dins and the extensive work on metabolites, it had level of statistical precision, from the NHLBI study become apparent that omega-3 fatty acids played an National Heart, Lung and Blood Institute!, suggest important role in inflammatory diseases and the im- that the daily dietary intake of 0.5 to 1.0 grams of mune system of the human body Lands 1986, Kinsella long-chain omega-3 fatty acids per day reduce the risk International By-ProductsConference 133

Table 1. Fatty acidsfound in fish oils. with the freshness of the raw material used in fish mealproduction. The mostcommon way to removethe 12:0 17:Branched 19:0 22:0 free fatty acidsfrom the oil is to saponifythem by 14:0 17:0 19:1 22:1 n-11 addingdiluted caustic soda to the oil. Theyare easily 14:1 17:1 20:0 22:2 removed afterward with water in a centrifuge. The 15:Branched 18:Branched 20:1 22:3 n-3 caustic soda also reacts with the triglyceride but at a 15:0 18:0 20:2 n-9 22:4 n-3 much slower rate. Finally the oil is dried before the 16:0 18:1 20:2 n-6 22:5 n-3 bleachingprocess Proceedings Lipidforum Symp. 1986, 16: I 18:2 n-9 20:3 n-6 22:6 n-3 Griffith 1986!. 16:2 n-7 18:2 n-6 20:3 n-3 23:0 Usually, fish oil has a rather unattractive dark 16:2 n-4 18:2 n-4 20:4 n-6 24:0 reddishcolor. This can be removed by addingpowdered 16:3 n-4 18:3 n-6 20:4 n-3 24: I clay or earth that absorbsthe color components.Then 16:3 n-3 18:3 n-3 20:5 n-3 the oil is filtered to remove the bleachingmaterial. 16:4 n-4 18:4 n-3 21:0 At this stage the oil is ready lor hydrogenation. 16:4 n-I 19:Branched 21:5 n-2 Hydrogenis addedto fishoil in thepresence of a catalyst to reduce the number of double bonds and saturate the Source: Leatherhead 1986. fattyacids. The melting point is controlled by the degree n = position of first doublebond counted from methyl of saturationand is checkedby measuringthe iodine group. valueor refractiveindex. After the desiredmelting pointis reached,the catalyst is removedfrom the oil by fi 1tration. It is sometimesnecessary to repeatthe refining and of cardiovasculardeath in middle-agedAmerican men bleachingsteps. After a secondbleaching, the color of by about 40%. the final product can be more easily controlled and it is Thesefindings havebeen published in the scientific alsobeneficial to removetraces of impuritiesthat might pressand have been taken up by the commercialmedia. be left in the oil. The secondrefining removesthe free This causeda suddeninterest in high-qualityfish oil, fatty acidsthat formedduring the bleachingand hy- highin omega-3fatty acids.The fish oil producersand drogenation process. the processorswere not readyfor sucha demand,since The last step is deodorizing, which removes the upto nowalmost all fishoil hadbeen hardened. During volatilecompound» that are the main cause if thestrong hydrogenation,polyunsaturated omega-3 fatty acids are fishy odorand flavor. Amongthe knowncompounds partly saturated and their health benefits ruined. removedby deodorizing are aldehydes,ketones, alco- Fish oil today is producedin fish meal factoriesas hols, hydrocarbons,and compoundsformed by heat a by-product.After thefish arelanded, they are stored decomposition of peroxides and pigments Griffith in holding pits at the factory until they are fed into the 1986!. The concentrationof thesecompounds is usual- cooker. Steamis usedfor cooking,and the temper- ly between200 and 1,000ppm beforedeodorizing. ature rises to 100'C while the raw material goes During deodorizingthe oil is heatedto 200' 250 C in throughthe cooker. In the next step the liquid is a vacuumof I 3 mm mercury and then stripped with removed,consisting of water, oil, and fine solids, usu- steam,which removesthe unwantedcomponents. The ally in a twin screw press. Then the decanterremoves oil then is cooled and is ready for use in the food small particles before centrifugation where the oil is industry. separatedfrom water. Finally, the fish oil is cooled Due to the health benefits of omega-3fatty acids, and stored. The oil from this processis defined as thereis increasinginterest among food manufacturesto crude fish oil. Guidelines for crude fish oil charac- startusing liquid fish oil insteadof hydrogenatingit. So teristics are shown in Table 2 Young 1986!. far unhardenedfish oil hasfew applicationsbecause of Figure 2 isa flow diagramfor the classicalprocess- its fishy flavor and stability problems. The highly ing of crudefish oil. The acid pretreatmentstep is polyunsaturatedomega-3 fatty acidscan be easily oxi- intendedto removeany gum material or phospholipid dized if not protected against oxidation and handled that mightinterfere with the qualityof the final prod- with care. If fish oil is usedin the food industryas a uct. Usually acid pretreatment is not needed for fish sourceof omega-3fatty acids,the producersmust guar- oil. The second step is refining. Crude fish oil al- antee a certain shelf life. The oil must also be able to ways containssome amount of free fatty acidsthat can endure baking and cooking procedureswithout dete- have deleterious effects on the final product. The rioration. This creates a certain dilemma for the fish oil amountof free fatty acids varies mainly in accordance producers,since the fish oil is a by-product. 134 Market Specifications

Table 2. Guideline values for crude fish oil characteristics.

Moisture and impurities Usually 0.5%, but sometimes 1% FFA as oleic acid! Ranges from 1% to 7%, but more usually 2% to 5% PV 3 to 20 meq/kg AV 4 to 60 IV 95 160 115 160 150-200 160 200 Anchovy 180-200 Color Up to Gardner 14 Iron 0.5 to 7.0 ppm Copper Less than 0.3 ppm Phosphorus 5 to 100 ppm Sulfur Levels of over 30 ppm will usually result in difficulty with hydrogenation

Source: Young 1986. FFA = free fatty acids; PV = peroxide value; IV = iodine value; AV = anisidine value.

Figure 2. Flo~' diagram fr>r processing crude fish oil. InternationalBy-Products Conference 135

Table3. Partitionof lipidsin capelininto fish meal and oil.

Capelin,whole Meal Oil Total lipids TL!, % of dry matter 32 13 100 Percentageof TL in whole fish 40 60 Neutral lipids, % of TL 77 60 97 Phospholipids,% of TL 16 24 I Fatty acid 8.1 14:0 6.7 4.5 9.0 16:0 1 1.3 15.9 1.1 18:0 1.3 2.0 8.7 16: I 8.2 7.6 17.4 18:1 17.3 16.0 24.9 20:1 20.5 10.0 19.5 22:1 15.6 7.1 2.9 20:5 n-3 5.3 10.5 1.7 22:6 n-3 7.4 17.9 1.4 Total n-6 1.5 2.0 6.3 Total n-3 15.3 31.6 FromN. Urdahland E. Nygaard970! unpublisheddata!. Source: Opstvedt1985.

When the raw material arrives at the factory, it is thefish. Thegreatest disadvantages of this method are usuallyseveral days old, anda fewmore days may go the high cost,limited numberof food-gradesolvents by beforeit is processed.This meansthat the raw that can be used, and the large volume of solvents material used is not fit for human consumption,and needed.However, high-quality oil canbe obtained with thereforethe oil is often of low quality. When the fish this method. oil ishydrogenated, thecrude oil qualityis not so crucial Recentlyanother extraction method has become sinceby hardeningthe oil, the polyunsaturatedfatty commercialized.This is SupercriticalFluid Extraction acidsare saturated. This meansthat oxidation problems SCFE!,which has been applied to severalprocesses in are more or less eliminated, so we should not get an thefood industry. SCFE utilizes the special properties offensiveflavor in thefully processedoil. Butif thefish of gasabove its supercriticaltemperature and pressure oil is not hydrogenated,higher-quality crude fish oil is to extract or fractionate compounds McHugh 1986!. needed. This meansit is necessaryto look into other Partlydue to economics, this method has been used only productionpossibilities besides improving the process. to remove undesirablecomponents from fish oil or to It is worthnoting that the oil part of capelinfish separateEPA and DHA from fish oil Northwestand meal containshigher amountsof EPA and DHA Alaska Fisheries Center 1985!. docosahexaenoicacid! of the omega-3family than Fishoil producerstoday have many possibilities to unprocessedcapelin fish oil. Thereason is thatmost of improvethe quality of crudefish oil. Improvedpro- thephospholipids that contain EPA and DHA are still in cessingtechnique and betterstabilizers offer higher- the fish meal, while the fish oil consistsalmost exclu- quality oil to the food industry. sivelyof mono-, di-, and triglyceri des Table 3! Opstvedt In all fish oil production,the quality and freshness 1985!. The conclusionis that in orderto obtainthe of the raw materialis of greatestimportance. After highest-qualityfish oil, preferablywith thesame com- beingcaught, the fish should be kept on ice until it is positionas in thefish, theemphasis must be on the processed.Chemical parameters such as TVN total productionof fish oil, withfish meal treated as a by- volatile nitrogen!should be monitoredto checkthe product. freshness.During processing, heating should be kept In thevegetable oil industry,oil is themain product to minimum.In thepresence of waterand pro-oxidants andmeal is a by-product.By usingfresh fish asa raw suchas copper and iron, fish oil canbe easily oxidized. materialand appropriate solvents, the mono-.di-, and Heat accelerates the oxidation process to a great extent triglyceridesand phospholipids can be extracted from and can also causeisomerization, polymerization, and 136 Market Specifications

loss of essential polygenic fatty acids. Table 4. Tasting results for foods prepared with The use of anti-oxidants early in the process is also refined fish oil. of great importance. Low-quality fish oil can never be upgraded by adding anti-oxidants, but high-quality Taste crude oil with anti-oxidants is much more stable during Food made comment processing and less prone to oxidation than fish oil with no anti-oxidants. Tests in Iceland have shown that the Spreads processing of fish oil such as refining, bleaching, and and pastes Fish spread Acceptable deodorizing reduces its stability if no anti-oxidants Cheese spread Good are added to the crude oil and after each processing step Peanut butter Acceptable Thorison 1990!. Salads and When liquid fish oil is used for human consump- salad dressing» Salad cream Acceptable tion, it is often necessary to add a winterization step to Mayonnaise Production the process. During winterization the oil is cooled to problems remove solid fat fractions that would normally cloud, Coleslaw Poor at refrigerator temperature, oil that is liquid at room Dairy products Yogurts Poor temperature. This also increases the amount of omega- 3 fatty acids in the oil. Oils and Due to increased ocean pollution, fish oil produced oil blends French dressing Good from fish caught in polluted waters contains some pesr Canned fish oil Good ticides, polychlorinated biphenyls, and other undesir- Sausages,smoked able contaminants. This is now a problem for the fish and spiced foods Salami Good liver oil producers since the liver collects these con- Pork sausages Good taminants. During deodorizing some of the compo- Source: Young 1990. nents are removed. Deodorizing can hardly be called a gentle process, especially for highly unsaturated oil. Therefore, oil processors have started to use a high- vacuum, molecular distillation apparatus to remove im- purities. The high-vacuum, molecular distillation acceptable flavor that contains fish oil. In Denmark process also removes the vitamins, some cholesterol, this past year, a commercial margarine product was and some oxidation products, and therefore purifies the launched containing 20% 25% unhydrogenated fish oil and makes it more stable against oxidation. oil and 7S% 80% vegetable oil Barlow and Young Let's now look at the markets. The market for 1988!. liquid fish oil for human consumption can basically be In order to include fish oil in infant formulas and in divided into three areas. baked products, processors have been looking into the possibility of using microencapsulated fish oil in order ~ As a commodity for the food industry. to solve the stability problem of the oil. The ~ As a health food. microencapsulation technique offers a very promising ~ As a pharmaceutical. solution. It is based on forming sub-miniature capsules or microcapsules consisting of a shell and fill material. From a theoretical point of view, fish oil may be Typical microcapsules are small enough to be used as a used in any food item that contains fat. The problem free flowing powder or suspended in water. The dis- that must be solved is how to introduce fish oil into advantage is that the volume of coating material is still food products without making them taste fishy. The very large compared to the fill material. This is now a most promising food application seems to be in mar- commercial product. garine, salad oil and salad dressing, mayonnaise, and In the fats and oils industry, intensive research several types of spreads and pastes. The International work is in progress in the field of enzymatic modifica- Association of Fish Meal Manufacturers IAFMM! tion, such as interesterification. Cocoa butter equivalents started trials in the United Kingdom in 1985 using fish are now produced by interesterifying mixtures of oils oil from different sources at different levels in several and fats Posorske et al. 1987!. Besides making triglyc- foods. The products included were French dressing, erides high in omega-3 fatty acids, enzymatic modifica- salad cream, frankfurters, salami, margarine, and may- tion opens up the possibility of modifying fish oil as onnaise Table 4!. The trials in general were success- a replacement for more expensive fat and oil sources, ful since they show it was possible to produce food or even to tailor-make triglycerides for specific uses. Intet.nationalBy-Products Conference 137

Crude oil

Figure3. Processingpossibilities for unhardenedfish oil.

Figure3 showssome processing possibilities for It hasbeen proven that fish oil dramaticallyaffects unhardened fish oil. thebiological activities in thebody Galli 1988!.Many It is very difficult to estimatethe market for clinical testsare underway, and the pharmaceutical unhydrogenatedfish oil. But it wouldnot beunreason- industryhas shown interest in the therapeuticapplica- ableto estimatethe U.S. andEuropean market, based on tion of fish oil concentrates. Whether the results can be fish oil asa supplierof omega-3fatty acidsat 150,000 harnessedinto useful specific therapiesremains to be tonsper year. This is based on daily dietary intake of 1.0 seen.At leastone company has registered encapsulated gramof long-chain,omega-3 fatty acids. fishoil asa drugin Europefor loweringblood fat. Many Although cod liver oil hasbeen sold for many years patentapplications have been approved making claims asa healthfood, a greatdemand has developed in thelast thatomega-3 preparations act as anti-cancer agents, and few yearsfrom the health food industry for fish oil thatthey could be usedfor prophylaxisor treatmentof containinghigh amounts of omega-3fatty acids,espe- vascular disorder, or even treatmentof disorderslike cially EPAand DHA. Severalfish oil productsare now Raynaudsdisease. How big thepharmaceutical market on the market. Most of them are basedon fish oil in will be dependson the resultsof the tests. The drug whichthe omega-3 content has been increased with cold companieswill alwaysdemand the mostpurified, filtration, solventextraction, SCFE, enzymatic treatment, highest-qualityfish oil fromthe fish oil industry,and or a combination of these. There are also on the market therefore has set standardsfor the fish oil processing omega-3fatty acidmono-esters and free fatty acids industry. producedfrom fish oil. Mostof theseoils arehighly During the last ten years, we have seen a new unstable,and althoughanti-oxidants and vitamin E marketdevelop in aquaculturefor fish oil asan ingredi- have been added,the oil must be specially protected. ent in fish feed. Lipids from wild fish containcompara- Most of these products are encapsulatedin a soft tively high levelsof omega-3fatty acids. The marine gelatincapsule that protects the oil. speciesthat are farmed today must get their omega-3 138 Market Specifications

Table 5. Potential use of fish oil in fish feeds, 1990.

Fish production Dry feed Fish oil Fish oil amount metric tons metric tons inclusion metric tons Fish species Area x 1,000! x 1,000! in diet %! x 1,000!

Salmon W. Europe 135 225 15' 34 Far East 30 50 15~ 8 N. America 25 40 15' 6 S. America 7 12 15 2 Trout Europe 182 328 10 33 N. America 80 145 10 15

Catfish N. America 150 300 2.5 and prawns Far East intensive! 120 240 Far East semi-intensive! 180 180 129 2 S. America semi-intensive! 30 30

Eels Far East 100 200 15' 30 Europe 8 16 15 3 Yellowtai1 Far East 150 150' 12 20 Milkfish Far Fast 300 1504 10 Crayfish N. America 50 10'- Total 2,076 190 ' Diets producedby cookerextrusion, allowing oil contentof finished diet up to 25 /o. '- Only a smallproportion of crayfish producedlikely to receivemixed feed. ' Some fish oil likely to be usedin moist feeds. Also will move to dry feedsbecause of pollution problemscaused by moist feeds, especially in Japan. ' Low-cost, carbohydrate-richdiet fed to milkfish with 10%to l5% fish meal in dry diets. However,maybe fish oil will also be included in the diet. Amount of mixed 1'eedused is limited; also use waste products fed directly. -' Watanabe 1988.

Source: Pike 1990.

fatty acids in the diet. Since the omega-3 polyunsatu- pounds. With improved separation techniques and rated fatty acids are an important part of the marketing more gentle processing methods, these oils might play image of fish as a healthy food, fish oil has become a an even more important role in the pharmaceutical vital feed ingredient. Recentstudies also indicate that and health food industry in the near future. omega-3polyunsaturated fatty acids from fish oil pro- tect the fry from various diseasesby improving the REFERENCES immune system. Production of farmed fish and crustaceans is cur- Anonymous. 1984. A History of British Cod Liver rently over five million metric tons annually, but only Oils. Martin Books, Cambridge, England. part of this production receivesmixed feed. The esti- Bang, H.O. and J. Dyerberg. 1972. Plasmalipids and mateddry feedrequirement in 1990is 2,076,000metric lipoprotein in Greenlandic West Coast Eskimos. tons. The amount of fish oil needed in the feed is in the Acta Med. Scand. 192:8594. range of 190,000 metric tons and will likely continue to grow in the coming years Table 5! Pike 1990!. Barlow, S.M. and F.V.K. Young. 1988. Food Manu- facture. October, p. 75. Although the emphasis has been on the marketabil- ity of the health benefits of fish oil, it is known that Crawford, M. and D. Marsh. 1989. The Driving Force. fish oil and fish liver oil contain other interesting com- Heinemann, London. International By-ProductsConference 139

Dyerberg,J., H.O. Bang, E. Stofferson, S. Moncada, and Thorison, S. 1990. Icelandic FisheriesLaboratories, J.R. Vane. 1978. Ficosapentaenoicacid and pre- unpublished data. vention of thrombosis and atherosclerosis'? Lancet Watanabe,T. 1988. IntensiveFish Farming: Nutrition 2:117-119. and Growth. Blackwell Scientific Publications, Galli, C. and A.P. Simopoulos. 1988. Dietary m-3 and OnsneyMead, Oxford OX2 OEL, U.K. P. 172. u-6 Fatty Acids. NATO ASI Series Vol. 171. Young,F.V.K. 1986.The Refining and Hydrogenation Plenum Press, London. of Fish Oil. IAFMM Fish Oil Bull. No. 17. Griffith, W.A. 1986. Further processingand usesof Young,V. 1990.The usageof fish oil in food. Lipid animal fats and fish oil. Proc. Symp. Fish Oil and Technology 2!. Animal Fats. Sponsoredjointly by Leatherhead Food R.A. and Federation of Oil Seeds & Fats Association International, Leatherhead, U.K. P. QUESTIONS AND ANSWERS 44. When Joel Cowger spokeyesterday on white fish Horisberger,M. andU. Bracco. 1987.Lipids in Modern mealproduction, he said to burnthe oil you Nutrition. Raven Press, New York. produce,or anyfish oil you producein Alaskafor Kinsella, J.E. 1987. Seafoodand Fish Oils in Human fuel becauseyou can't make any money from it. Health and Disease. Dekker, New York. Is theprocess used here to producefish meal and oil Lands, W.E.M. 1986. Fish as Human Health. Aca- damagingto the oil in any way, or is it simply a demic Press, New York. matter of economics? I noticed on one of your graphsthat the omega-3 content in Alaskapollock Marcuse, R. ed.!. 1986. ProceedingsLipidforum liver oil is quite high. Symp. Animal Fat: Resources-Properties-Refin- ing-Application. ScandinavianForum for Lipid In producingcrude oil andraw material,freshness Research and Technology, Oslo. is the most important thing. When you start pro- cessingthe oil after that, then you have to be very McHugh,M. and V. Krukonis. 1986. Supercritical careful about the processingtechniques. Pollock Fluid Extraction. Butterworth, London. oil also contains some vitamins, and it has been sold Nelson,A.M. 1972. Diet therapy in coronarydisease. asa verygood omega-3 source in fish feed,espe- Effect on mortality of high-protein, high-seafood, cially eel feed in Taiwan. It is very possibleto use fat-controlled diet. Geriatrics 27:103. that oil for humanconsumption as a food ingredi- Northwest and Alaska Fisheries Center. 1985. National ent. One has to be careful to keep the oil separate, Marine Fisheries Service, U.S. Department of have everything clean around it, and treat it very Commerce. Quart. Rep. Oct. Dec. gently. But youneed to processfurther than crude oil. Opstvedt,J. 1985. Fish Lipids in Animal Nutrition. IAFMM Technical Bulletin No. 22. Norwegian Is the productionof fish mealand oil in Alaskaa Herring Oil and Meal Industry ResearchInstitute, problemof oil quality,if theydo not separatethe livers out on pollock? Norway. Pike, I. 1990.The Role of Fish Oil in Feedsfor Farmed A. Fish liver oil contains vitamins, and it is not logical Fish. IAFMM Technical Bulletin No, 25. to include it in food simply becauseyou would get an overdose of vitamins. You can add it effectively Posorske,L.M. et al. 1987. Processconsideration of only up to a certainpoint. In orderto collectliver continuous fat modification with an immobilized oil you must separateit by hand,and processit lipase.Paper presented at the 78th Annual Meeting separately.The cost is prohibitivebecause fish of the American Oil Chemists Society, New Or- liver oil must competewith vegetableoil prices. I leans, Louisiana, 1987. am convincedthat food processorswill not be able Second International Conference on the Health Effects to, or be willing to, pay any high premium for fish of Omega-3Polyunsaturated Fatty Acids in Sea- oil. It hasto competewith soybeanoil, corn oil, etc. food. 1990.Washington D.C., March 20 23, 1990. Q Almostall thepollock landed in Alaskais held in FAO and WHO. Press release. RSW vessels,refrigerated sea water, and delivered Simopoulos,A.P. 1986.Review: Omega-3 fatty acids at mostwithin two daysof catch,more like 24 hours in health and disease. J. Nutr. Growth Cancer 3:69 of catch. Do you know of any effect on the raw 71. materialthat might have?What aboutsalt uptakein 140 Market Specifi'cations

the livers? obtain esters at 95% purity of both EPA and DHA.

A. The problem with collecting livers at sea is that Q. Mr. Goddard! In our salmon processing plants in most of the bottom trawlers, factory trawlers, are Kenai we have available to us on the order of one now mechanically gutting the fish, and that means million pounds of salmon heads a year. Is there any that a specialperson separates the liver. The best economically viable application for extracting thing is to put the liver into a plasticcube and ice it, omega-3oils from salmonheads that could be done and if you processit within four or five days, you in a small application without an attendantmeal will able to get quality fit for humanconsumption. plant? I'm referring to the trawlers that deliver whole fish A. There is already a small market for salmon oil in to shore-basedplants where the pollock hasbeen in capsulesas a healthfood. And alsofrom a marketing RSW tanks for 24, 30, to 36 hours. point of view, peopleprefer to have omega-3oils from salmon to other types of fish. So that is an A. If it is well cooled, you could get the liver. If you advantage.But I have seennothing of the salmon get it out within 24 hours, you would be able to oil maybe it's not so different in fatty acid com- processwith good quality. The condition of the position from other modified oils. This comes fish is also important. If it is close to a spoiling aroundagain to the cost of producing it. Is your oil stage,etc., the liver deterioratesfast. competitivewith other oils similar in composition? Is there a market for fish oil in the manufacture of There is a market for this; I would estimate 50 to soaps? 100 tons a year. A. Not any more. Now there are cheapersources of Q. Out of a million pounds of salmon heads, how oil. Fish oil is not competitive in most of the much oil do you think could be produced? industry any more. Todaywe haveonly limited use for fish oil in the margarine and shortening in- A. Fifteen percent. dustry as hydrogenatedoil, and also in fish feed. Q. That would be substantial. That would be some- There is a good possibility in the near future that thing on the order of SOto 70 tons. food manufacturers will use fish oil in blends with A. In our company,we have looked at the fatty acid vegetableoil. The dietary recommendationis that composition of the salmon viscera, and we found you should have approximately the ratio of 4:1 the oil very disappointing in omega-3 fatty acid vegetable oil:fish oil. content. But the oil from the head must be very Q I am from a developing country. If fish oil is used interesting. in the manufacture of soaps, is there a problem with As a commercial application from a processor's deodorizing'? Or is the manufacturing process a viewpoint. it would be a lot easierto segregatethe deodorizing process as well? heads and to deal with them than the viscera. I'm If you use it as a soap, you would first partly assumingthat a simple boiling processwould be hydrogenateit in order to get the right saturated sufficient for extracting most of the oil and then state of the fatty acids. When you do that, you follow with some sort of crushing. solve most of your off-flavor problems. A. Yes. Also I think it would be very interesting to In an early slide, you showed a specification that look at the composition of the oil. How much is listed a tolerance for sulfur. What's the source of phospholipid, how much is triglyceride; if you that sulfur? It shouldn't be in refined fish oil unless could get someof the phospholipidsout, you would you have contamination from protein. have much stronger marketing potential. So you A. Someproteins contain sulfur, andwhen the protein should look at your method of producing with this deteriorates and breaks down, some of the sulfur is in mind. Not only look at triglycerides, but look at released to the oil, I believe. the type of fat left in the head after boiling and separating the oil. Was that specificationfor hydrogenatedoil? Boiling and separatingis probably the simplest. Yes. Sulfur affects the catalyst in the hydrogena- Q tion process. The cost of hydrogenation increases A. Yes, that's the simplest, to grind it very well, and because you have to add an extra dose of metal then to boil it and press it out. I'm certain you will catalysts. get all the oil you would like to get out of the flesh Mr. Nelson! At our laboratory we' ve been doing of the head. extraction work in fish oils. We' re now able to What do you estimatefor the commercialvalue of InternationalBy-Products Conference 141

somethinglike that in raw form'? is a routine analysis,and I am pleasedto confirm that we have a reduction of compounds like DDT A. I estimateyou would get $2,000 to $3,000a ton. and PCBs. The contaminants are usually in very Q. If we can produce 50 tons a year, that makes it closedareas such as fjords, and they are far below interesting. the legal levels. On the other hand,consumers are A. You have to be very careful to have a balance scaredif theyknow there are even small traces of between the demand and the supply, because you anycontaminants in theoil. Thereforeone has to be could overflow the market. verycarel ul aboutremoving contaminants in order to state that the oil is contaminant free. Q. I have a question about environmental contam- inants in fish oil. I'm wondering whether you And are they actually removed,or are they altered regularlyanalyze your products or yourcrude oil. by the processes? A. Removed. They are absorbed through the A. Yes, we do. bleaching clay, and then during the deodorizing Q. Is it a consumer issue? processmost of thevolatile compounds are distilled A. No, we do it on a regular basis becausewith this off. Further removal occurs if we use supercritical modernanalytical techniqueyou can detectpesti- extraction, or high-vacuummolecular distillation. cides and some foreign bodies in almost any oil, We usethe latter processesmainly for specialhealth to one part per trillion. We monitor the levels, productsand for pharmaceuticalproducts because althoughthey are far belowany legal limits. This theymust be completely free of anycontaminants.