Department of the Environment Fisheries Research Board of Canada Halifax Laboratory

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1 ,7-) X?. c»/ FISHERIES RESEARCH BOARD OF CANADA Translation Series No Storage experiments with herring and small pollock in refrigerated seawater. The effect of additives CO and K-sorbate 2 by Olaf Karsti, and Olav Grenmyr Original title: Forse med lagring av sud og pale i kjelt sjevann. Effekten av hjelpestoffer - CO 2 og K-sorbat From: Fiskeridirektoratets kjemisk-tekniske forskningsinstitutt : Translated by the Translation Bureau(sow) Multilingual Services Division Department of the Secretary of State of Canada Department of the Environment Fisheries Research Board of Canada Halifax Laboratory Halifax, N.S pages typescript

2 DEPARTMENT OF THE SECRETARY OF STATE TRANSLATION BUREAU MULTILIPGUAL SERVICES DIVISION reel ve eee,:e eke>1 CANADA SECRÉTARIAT D'ÉTAT BUREAU DES TRADUCTIONS DIVISION DES SERVICES MULTILINGUES TRANSLATED FROM - TRADUCTION DE Norwegian AUTHOR - AUTEUR TITLE IN ENGLISH - TITRE ANGLAIS INTO - EN Olaf Karstl and Olav Gronmyr English 9 Storage Experiments with Herring and Small Pollock in Refrigerated Seawater. TITLE IN FOREIGN LANGUAGE (TRANSLITERATE FOREIGN CHARACTERS) TITRE EN LANGUE ÉTRANGÉRE (TRANSCRIRE EN CARACTÈRES ROMAINS) Forek med lagring av slid og pale 1 kelt sevann Effekten av hjelpestoffer CO2 og K-sorbat REFERENCE IN FOREIGN LANGUAGE (NAME OF BOOK OR PUBLICATION) IN FULL. TRANSLITERATE FOREIGN CHARACTERS. RÉFÉRENCE EN LANGUE ÉTRANGÉRE (NOM DU LIVRE OU PUBLICATION), AU COMPLET, TRANSCRIRE EN CARACTÈRES ROMAINS. N.A. REFERENCE IN ENGLISH - RÉFÉRENCE EN ANGLAIS N.A. PUBLISHER- ÉDITEUR Directorate of Fisheries Chemical-Technical Institute PLACE OF PUBLICATION LIEU DE PUBLICATION Bergen, Norway YEAR ANNÉE Oct, 1970 DATE OF PUBLICATION DATE DE PUBLICATION VOLUME ISSUE NO. NUMÉRO PAGE NUMBERS IN ORIGINAL NUMÉROS DES PAGES DANS L'ORIGINAL 13 NUMBER OF TYPED PAGES NOMBRE DE PAGES DACTYLOGRAPHIÉES REQUESTING DEPARTMENT TRANSLATION I BUREAU our, NO. Environment MINISTÈRE-CLIENT NOTRE DOSSIER N BRANCH OR DIVISION DIRECTION OU DIVISION PERSON REQUESTING DEMANDÉ PAR r'isheries Services A.T. - - Reid -- TRANSLATOR (INITIALS) TRADUCTEUR (INITIALES) SOWF SEP YOUR èlumber VOTRE DOSSIER NO DATE OF REQUEST DATE DE LA DEMANDE (REV. 2/66) i\l`isl11ion LINODITED or» Vie i n (orrna'fi on 111A01.1Cl'ION NOt's1 111.:VIS>01 Inionon.;lon seulement-

3 DE Pe RTMENT OF THE SECRETARY OF STATE TRANSLATION BUREAU MULTILINGUAL SERVICES DIVISION SECRÉ TA RIA T:D "É TA T BUREAU pgs-trapperions DIVISION,PES SERVICES MU LIE IL ING U gs CLIENTS NO. DEPARTMENT DIVISION/BRANCH CITY NO DU CLIENT MINISTÉRE DIVISION/DIRECTION VILLE Environment Fisheries jervices Uttawa unt. BUREAU NO. LANGUAGE TRANSLATOR ( I NI TIALS) N DU BUREAU LANGUE TRADUCTEUR (INITIALES) Norwegian SOWF SEP DIRECTORATE OF FISHERIES CHEMICAL - TECHNICAL RESEARCH INSTITUTE Storage Experiments with Herring and Small PoIloe,in Refrigerated Seawater Effects of Additives CO2 and K-sorbate by Olaf Karstl & Olav Gronmyr klfiermaiion scukunent; SOS

4 Storage Experiments with Herring and Small Pollock in Refrigerated Seawater Effects of Additives-0O2 and K-sorbate Abstract The aim of the continued storage experiments with fish in refrigerated seawater is to investigate some changes which occur during storage at 0 00 when CO2 and Page 1 K-sorbate are added. The report covers a preliminary investigation. Supplements will be issued later, Raw Material Test Plan and Method Two experiments were carried out; one with large herring and one with small pollock. The herring was oaught at the Sula fishing grounds and placed on ice in Kristiansund N. On receipt in Bergen e the fish was approximately :tihree days old, The quality was good, and judged satisfactory for fresh herring, but the consistency was slightly reduced, The fat content was 8.8%, When received in the laboratory, the herring was immediately. hosed down with water and distributed in lots of twelve herring. The lots were then weighed and numbered, The small pollock was purchased in Bergen. It was alive when received and immediately killed and cleaned, The

5 - 2 heads were removed. After rinsing with water, the fish was distributed in lots of six fish, Ithich were weighed and numbered in the same manner as the herring. The types of storage used during the tests with both herring and small pollock included: Type 1 - Storage in -: water 4 3% NaCi Type 2 - Storage in water -k 3% NaC ( atm.) Type 3. Storage in water.1. 3% Na Cl 4) 0,67% K-sorbate To cover the fish adequately, the relationship of water to fish,which traditionally is 1:4 in industrial storage in refrigerated seawater, had to be increased. In the tests the relationship of water to herring was approximately 1:2,5 and water to pollock approximately 1:108. A fifty litre *container was used for the tests. The required refrigeration during storage was achieved by placing the containers with water and fish in cold storage at 0 C. The containers with water were cooled to 0 C before the fish was placed in the container. In Type 2 storage the containers were equipped with a pressure gauge, valves and supply tube for introduction of CO2 from a pressure bottle. The water was saturated with CO2 and kept at a positive pressure of i atm. In test No. I, each test series (container) had four strings of fish with twelve herring on each, and in test No. II, each container had four strings of fish with six small pollock on each. The content of CO2 in the water

6 during Type 2 storage was determined:. The absorption of water, salt and K-sorbate during storage was registered by weighing and alalysis of herring and pollock at the start of the test and during each removal. The reduction in fl.sh quality during storage was determined by measurements of. organology and chemical analysis of trimethylamine-n, total volatile N, fat and free fatty acid. All measurements were carried out in accordance with accepted procedures, Test Results I Herrtno. In the tests with herring the samples were analysed and assessed after 0, 3, 6, 10 and 13 days storage. shown below. The CO2-content in the water from Type 2 storage is Table].. CO2 content in water from Type 20 bmorage time in aays O.5 b g CO2/100 ml water 0,27 0,31 0,34 0,35 0,35 When assessing the quality of the samples from the throe types of storage after a storage time of three days. (six days for herring) it was established that the quality was good but slightly reduced. The herring from Type 2 (CO2) and "Type 3 (K-norbate) had a fresher smell than from Type 1, and the appearance of the herring from Type 3 (K-aorbate) was probably slightly better than the others.

7 After a storage time of six days (nine days for herring) water and herring from Type 1 were observed to smell poorly; a less bad:smell was noted in Type 2 (00 2 ) and Type 3 (K-sorbate) The herring from Types 2 and 3 was little better in appearance. The consistency of all samples was slightly soft. The herring from Type I was possibly also slightly more red in the belly than the other samples but the difference was small. After a storage period of ten days (thirteen days for herring) the quality was further reduced in all samples. The herring from Type 1 storage was as in the previous assessments, in the worst condition (spoiled) while the herring from Type 2 (00 2 ) and Type 3 (K-sorbate) were possibly usable. Borne burst bellies were noted, particularly in Type 2 and 3. It was also apparent that the herring from Type 1 was slightly more red coloured in the meat, but the difference was less than before. After a storage period of thirteen days (sixteen days for herring) the limit of durability was reached for all samples. Type 1 storage was terminated as indicated above. The other samples were, after a storage time of thirteen days, almost uneatable, but appearance and smell were relatively good.

8 Analysis of the samples after 0, 3, 6, 10 and 13 days storage provided the values ishich are shown in Table 2, - Figures 1 and 2* The value for quality is an average for appearance, smell, taste, consistency and rancidity, The CO2 content in the water increased during the first six days of storage and remained constant thereafter. After six days storage, the absorption of salt and sorbate reached a level of approximately 0.7 and 0.06%, respectively. The weight increase (absorption of water) climbed during the total storage period, After 13 days storage, the values were approximately 5%. The weight increases for the three types of storage indicate that herring stored in seawater with CO2 (Type 2) absorbs less water than herring stored in seawater. without CO2 while the values for Type 3 (K sorbate) was - slightly higher than in Type 10 The organological estimates of the herring in raw and boiled condition confirm that slightly better durability is reached when storing herring in refrigerated seawater saturated with CO2 or seawater with K sorbate added than what is reached during storage in water without CO2 or sorbate. The smell from the water and herring in Type 1 (Figure 1) was essentially poorer than in Types 2 and 3 and the difference in taste was gradually more noticeable. Chemical analysis of the content of trimethylamine N and total volatile N (Table 1, Figure 2) confirmed that CO 2 and

9 6 K-sorbate addition had a marked effect and the values indicated a lower micro-biological activity than in Type 1. The used concentration of K-sorbate (Type 3) provided the lowest values for trimethylamine-n and total volatile N.. Next came Type 2 storage while the values for Type 1 were the highest.

10 r- Table 2. Analysis and quality assessment of herrine stored in water.1. 3% Nan with and. without CO2' (i atm.) and 0,67% K-sorbate, after 0, 3, 6, 10 and 13 days storage at 0 C. Analysis Organolôglcal, Assessment Raw Boiled Test Series Time Weight NaC1 Sorbln in Increa Acid Days se % % g/100g Fat F.f.a. : Trime thy Total lamine Volatile-N g/100g mgn/100g mgn/100g App Cons Cons s Rn-_ru al o ld! Va] ty us. FPw Material 0 8,81 3,2.1,0 13, ' 1.5 7,7 2,8 13, ,6 15,1 30, ,0 6 3, 0 7,0 6,2 8,6 33,2 1,3 2, ,3 13, ( c0 2) 3 (K-sorbate) 10 4,0 13 5,0 3 3,5 6 5, ,7 0,6 0, 8 0,8 0,06 0,06 0,09 0,09 5,1 6,4 6po 6,8 7,3 7,7 7,7 5,7 7,3 6, ,7 1, 8 2,2 3,2 4,4 1 22,8 29,3 12, , , , , _ g spoiled , ' spoiled 4.0

11 CO2 in water, g/100 ml. tr.d'à 171')F11 SDC.C.. l e o Absorption of NaC1, g/100g Jae. tiarauffloè amemdboa *.lormaraje Q,3 0,9 owe 8"e 3 2.0, days :43 days Wei:gt.t increase, g/100g _Absorption of sorbine acid, g/10 jet"' aeie#4.., ee"'«tes %be. 1 gee... PK); R sge :. 7 dàys.. Appearance... Smell ent3.2-3.D IfCrring stored: in...a :rde., 2) 3) water plu,s biac1 CO2 ( atm) - co) /2 ota) qrbmt. K-sorbate

12 Consistency ICA8.1.ostene. Taste autelc àays Free fatty acid % lee!. tottoyre ", ' ", 13 6 _Qua].iity Value, eeq,. wee /le \\I\ days days Trimethylamine-N Tr it-xi terealn rod/±00,g':' ' 71: 3, 10 'Total Volatile 'N Ja,g4100s 5 2 f / /e" / 3 day s 110 tt..*jeo,,yee / '4""e 3 days 3 6: q.b.ert. _ dp.,_fen Fig. 2. Herring stored in: water plus 3 5 Nan. nr,l2. Slid '1..Qailrot es Dafq... 1.) VM311 ea ere.. ' - + CO2 a- atm) é, % 2) , (.2 P., 1%) t ,67% 1C- tiorbate. -

13 10 The values for free fatty aoids varied slightly, but showed a more rapid increase in Type 1 storage than Ene_i in Type 2 (002). Type 3 (K-sorbate) showed a slightly higher level than Type 2, Complementing investigations have shown that these values to some degree are influenced by the fish content of K-sorbate. Accordingly, the values for Type 3 storage only give a partially correct picture of the free fatty acid content. Some of the herring samples showed an insignificant amount of rancidity, probably due to the quality of the raw material which was slightly reduced (a târee day delay) on receipt, It is also reasonable to assume that the effect of 002 and K-sorbate as indicated by the differences in quality of'fish from storage in Types 1, 2 and 3 would in fact be greater if the herring raw material is fresh at the start of the tests, II, Small Pollock During the tests with small pollock, the samples were analysed and assessed after 0, 7, 13, 18 and 22 days storage, shown below. The CO2 content in the water from Type '2 storage is Content of CO2 in water from Type 2 storage. Storage time in days! $ 1 * **. g CO2/100 ml water 0,25 02 J_ 030 0,

14 When assessing the quality of the samples from the three types, after seven days storage, it was round that the quality for all samples was as good as fresh fish and the containers with the water and fish had a satisfactory, fresh smell, After 13 days storage the quality was slightly reduced in all samples. Water and fish from Type I smelled poorly and analysis showed that the limit of durability was reached. The smell from Type 2 and 3 was more moderate and the samples looked good. The fish from Type 2 (CO2) appeared slightly stiff but when cut released gas and liquid and the stiffness disappeared. It was found that the cut surface of the fish was porous This has previously been noted during storage of fish in a CO2 atmosphere. After 18 days storage it was found that the quality Page 8 of fish from Types 2 and 3 storage was also severely reduced. (Type I was terminated after 13 days.) Some smell was evident from water and fish but not as bad as from Type 1 after 13 days. The fish from Type 2 (CO2) was as before porous and released gas and liquid when cut. The quality was assessed as barely acceptable for use, The fish from Type 3 (K-sorbate) was of a soft consistency but slightly better than the other. One sample from Type 3 was therefore stored for an additional four days,

15 After 22 days of storage the limit of durability was reached and there was no longer any point in continuing. The analysis of samples of small pollock after 0, 7, 13, 18 and 22 days storage provided the values as shown in Table 4, Figures 3 and 4, Analysis of the results showed a slow increase in content of CO2 in water during storage, at a level insigni. ficantly lower than in the tests with herring. The fish absorption of salt increased during the 13 first days to approximately 0.8% and the determination of sorbine acid showed that after days storage a content of approxi- Mately 0.1%, that is, slightly higher than the values for herring. The weight ineréase (absorption of water) was after seven days storage approximately the same for all of storage. After 13 days the weight absorption three types was largest for Type 1, slightly less for Type 3 (K-sorbate) and smallest for Type 2 (CO2), (6,5, 4,3 and 1.8% respectively). It appeared that the water absorption in Type 1 was slightly higher for small pollock than for herring and slightly lower in Types 2 and 3. For Type.2 (00 2 ) a lower water absorp. tion was noted after 18 days than after the shorter storage period. This probably is related to the fish becomming gradually more porous. This was not so noticeable in the tests with herring,

16 1 3 The values for the organological evaluation of small pollock in raw and boiled condition confirmed the impression received during the tests with herring. The difference in quality related to types of storage gradually became larger. Type 3 (K eorbate) was more durable than Type 2 (CO2) while Type I was poorest. As in the tests with herring, large variations were noted in the values of trimethylamine and total volatile N. The values for free fatty acid corresponds with the impression received during tests with herring and confirms an essentially more rapid increase in the values for samples from Type 1 than from Types 2 and 3. As in the tests with herring, the values for (Translators note: in copy provided.) Line missing

17 ri Table 4. Analysis and quality assessment of small vollock stored in water 4. 3% NaC1 with and without 002 (i atm.) and 0,67% K-sorbate, after 0, 7, 13, 18 and 22 days storage at 0 C. Analysis Organological Assessment» Raw Boiled, Test Time Weight Nan Sor- Trimethy[Total 'F.f.a. Series in Inc- bine lamine Vola- App.Smell Cons AppiSmel/ Cons. Taste Quai. Days rease Acid tile-n Value % g/100g mgn/100g i mgn/100g g/100 1-> Raw Eate rie.1 0 0, 02 0,6 14,7 17, ,0, 7 1,3 0,6 0 4,5 16, ,5 0,9 0 23,5 43,5 72, (00 2 ) 1,1 0,5 0 2,5 16,4 26, , , ,8 0,8 0 3,9 20,3 29, ig 0 0,8 0 6,9 25,9 34, ,2 0,5 0,9 13,0 40, ,3 0,8 1,8 14,8 43, (K-sor 18 3,8 0,9 0,09 4,4 19,0 47, ,g bate) 22 3,9 0,9 0,11 6,1 22,4 51,0_ j J 3.0

18 - 15 CO 2 in water, g/100 ml. Ob!L vela% at Absorption of Nael, g/locig. Q22':e>o,.4 olfre,-43. mesee ""sees ' E45 éte days Weight increase, g/100g Vfflielm Absorption of sorbine acid, g/100e Ut3leJ9! "e b121/193 -Serwea days tlefe Appearance ploarlito r Smell Let, St71`...--e..,. 2 1\b' I. v 2 0,, 11004: ee, 23 a 2.22 days ate Fig. 3 qinel Pollock stored! water plus 3% NaC1 rics_â. nrb12. lospee. k: II) 7e,:nzl `f.a.G1.+. co 2 ( atm) 2) r c0,2, ( 1/2 0:t) 3i s.... _. 4. 0,. 1" U-ao rbet,. + 0.,67%1C-sorbate

19 - 16 consistency eopinne. Taste S..walt *.. eb:*;"z'e* ,.. _." 1 2 %%bit -a. Ns.. day s clays e d tie.. GO 3 4 orde ' r. e<eee4e. 2...be mowee. rei. qotfwv/ *, _.. Free fatty acid %.. 13 days Trime thylainine-n 301*, utpuezimin _ ee'l 201* lee 3 'eee. #e". J 10 2 wew, 4.t eeeee.. 13, (1. en_. 7.,. _ Fig... smial pollôck..sored in: e Nan,Pm1a. 1D.eret. 1) WIFPWrlIft c92 (2.P.tm) 2) 3) 10 rene_r let 11_11 _ Total Volatile N. W 2. 14, 0.67%. g-aorbai's 4: 0,67% K.:1Da.t ẹ. days

20 - 17 Summary_ and Conclusion The tests concerned a study of the effects of Page 12 CO2 and K-sorbate additives in storage of herring and small pollock in refrigerated seawater. The types of storage were: 1) 3% seawater 2) 3% seawater saturated with CO2 (.1- atmosphere positive pressure) and 3) 3% seawater with 0.67% K-sorbate added. The temerature during storage was The weight increase, letter absorption, Nan and K-sorbate absorption was registered and quality changes during storage was determined by chemical analysis and organological assessment of the samples, The results indicated that the absorption of water, salt and sorbate increased during storage depending on method, type of fish and storage time, The applied concentrations of CO2 and K-sorbate had a distinct influence on fish durability and quality during storage. The differences in quality became more pronounced with time. Samples from Type 1 storage smelt poorly after six to eight da.ys of storage while the samples from Types 2 (002) and 3 (sorbate) had a more moderate smell. Chemical analysis of trimethylamine-n and total volatile N, indicated that the addition of K-sorbate had the largest

21 effect, followed by the samples stored in refrigerated seawater and 002, while the samples stored in refrigerated seawater without additions, had the highest values. Fish stored in refrigerated seawater and 00 2 gradually became porous and when eut released liquid and gas. This became particularly pronounced during tests with small pollock (lean fish) and made the fish less suitable for eating or raw material for frozen fillet. The changes in consistency of herring due to 002 were less noticeable and did not have the same significance for the further use of the herring. Bergen, October 1970.