ISSN 2308-4057 (Print),
ISSN 2310-9599 (Online)

Hydrolysis products from sockeye (Oncorhynchus nerka L.) heads from the Kamchatka Peninsula produced by different methods: biological value

Introduction. Sockeye salmon (Oncorhynchus nerka L.) is a valuable Pacific salmon. Sockeye heads are a significant share in processing sockeye salmon. Traditionally, fish by-products are used to make fishmeal. However, due to the high content of collagen proteins and fat in sockeye salmon heads, it is difficult to produce fishmeal from this raw material. Controlled enzymatic or combined hydrolysis allows protein, fat, and minerals to be extracted to supply the market with higher value products with desirable features. This research was aimed to analyse the chemical composition and biological value of hydrolysis products obtained from sockeye heads.
Study objects and methods. We investigated hydrolysis products of sockeye salmon heads, namely protein hydrolysates, fat and sludge. Thermal hydrolysis and enzymatic-thermal hydrolysis were used for the tests. Thermal hydrolysis was realized in reactor. For enzymatic-thermal hydrolysis, the raw material was pre-treated by proteolytic enzyme Alcalase. The hydrolysates obtained were investigated. Chemical composition was determined in accordance with State Standard 7636-85. HPLC was used for molecular weight and amino acid analysis. Gas chromatography was used for fatty acid analysis. Biological value of proteins was determined by the balance of the amino acid composition comparing it with the “ideal protein model”.
Results and discussion. Thermal hydrolysis resulted in the production of protein hydrolysate powder with protein content of 92.0% dry matter and a protein recovery rate of 39.6%. Combined hydrolysis resulted in the production of protein hydrolysate powder with protein content of 92.6% and a protein recovery rate of 83%. All protein hydrolysates contained all essential amino acids. The biological value of protein hydrolysate obtained by thermal and combined hydrolysis was 80.1 and 82.8%, respectively.
Conclusion. Hydrolysed products obtained by thermal and enzymatic-thermal hydrolysis had a valuable chemical composition and could be recommended for food and feed use.
Fish, by-products, sockeye, hydrolysis, amino-acid profile, peptides, protein
  1. Rosrybolovstvo zayavilo o rekordnom vylove tikhookeanskogo lososya v 2018 godu [Russian Federal Agency for Fishery (Rosrybolovstvo) announced a record catch of Pacific salmons in 2018] [Internet]. [cited 2019 Jan 15]. Available from:
  2. V 2018 godu uchenye rekomenduyut k vylovu 492 tys. tonn lososey na Dalʹnem Vostoke [In 2018 the scientists recommend to catch 492 thosand ton of salmon in Far East]. [Internet]. [cited 2019 Jan 18]. Available from:
  3. Podvedeny itogi rekordnoy putiny 2018 na Kamchatke [The results of the record season in 2018 in Kamchatka are summed up]. [Internet]. [cited 2019 Jan 18]. Available from:
  4. Volkov VV, Grimm T, Lange T, Mezenova OYa, Hoehling A. Study of different hydrolysis methods of pacific salmon by-products using sockeye (Oncorhynchus nerka) heads as an example. KSTU News. 2017;(45):126–146. (In Russ.).
  5. Edinye normy otkhodov, poterʹ, vykhoda gotovoy produktsii i raskhoda syrʹya pri proizvodstve okhlazhdennoy, morozhenoy i kormovoy produktsii iz gidrobiontov morskogo promysla i pribrezhnogo lova [Uniform rates of waste, losses, finished product yield and raw material consumption in the production of chilled, frozen and fodder products from aquatic organisms of marine fishing and coastal fishing]. Moscow: Goskomrybolovstva; 2004. 164 p.
  6. Kizevetter IV. Tekhnologicheskaya i khimicheskaya kharakteristika promyslovykh ryb tikhookeanskogo basseyna [Technological and chemical characteristics of commercial fish of the Pacific basin]. Vladivostok: Dalʹizdat; 1971. 297 p. (In Russ.).
  7. Simakova IV, Giro TM, Vasilyev AA. Ensuring the safety of the lipid fraction of semi-finished products of a high degree of preparation from fatty fish raw materials. Foods and Raw Materials. 2018;6(2):449–456.
  8. Hoeling A, Volkov VV. Proteins from by-products – innovative components in sustainable industrial production. KSTU News. 2015;(38):83–92. (In Russ.).
  9. Pasupuleti VK, Braun S. State of the art manufacturing of protein hydrolysates. In: Pasupuleti VK, Demain AL, editors. Protein hydrolysates in biotechnology. Dordrecht: Springer; 2010. pp. 11–32.
  10. Hoeling A, Grimm T, Volkov VV, Mezenova NYu. Hydrolysis process of fish cannery by-products. Journal of International Academy of Refrigeration. 2016;(1):3–8. (In Russ.).
  11. Gustafson RG, Wainwright TC, Winans GA, Waknitz FW, Parker LT, Waples RS. Status review of sockeye salmon from Washington and Oregon. NOAA Technical Memorandum; 1997. 282 p.
  12. Lipatov NN, Sazhinov GYu, Bashkirov OI. Formalizovannyy analiz amino- i zhirnokislotnoy sbalansirovannosti syrʹya, perspektivnogo dlya proektirovaniya produktov detskogo pitaniya s zadavaemoy pishchevoy adekvatnostʹyu [Formalized analysis of the amino and fatty acid balance of raw materials that are promising for designing baby food products with a given nutritional adequacy]. Storage and processing of farm products. 2001;(8):11–14. (In Russ.).
  13. Neklyudov AD. Tne isolation collagens from distinct organs and texture of mammalians. Ecological Systems and Devices. 2005;(11):27–36. (In Russ.).
  14. Remarkable salmon protein hydrolysate from Norway [Internet]. [cited 2019 Jan 15]. Available from:
  15. Nishida C, Uauy R, Kumanyika S, Shetty P. The Joint WHO/FAO Expert Consultation on diet, nutrition and the prevention of chronic diseases: Process, product and policy implications. Public Health Nutrition. 2004;7(1):245–250.
  16. Ghaly AE, Ramakrishnan VV, Brooks MS, Budge SM, Dave D. Fish processing wastes as a potential source of proteins, amino acids and oils: A critical review. Journal of Microbial and Biochemical Technology. 2013;5(4):107–129.
  17. Slizyte R, Rommi K, Mozuraityte R, Eck P, Five K, Rustad T. Bioactivities of fish protein hydrolysates from defatted salmon backbones. Biotechnology Reports. 2016;11:99–109.
  18. Protein quality evaluation. Report of the joint FAO/WHO expert consultation. Rome: FAO; 1991. 67 p.
  19. Derkach SR, Grokhovsky VA, Kuranova LK, Volchenko VI. Nutrient analysis of underutilized fish species for the production of protein food. Foods and Raw Materials. 2017;5(2):15–23.
  20. Zarubin NYu, Frolova YuV, Bredikhina OV. Development of a multifunctional complex based on the raw materials of animal and vegetable origin for use in semifinished fish technology. Proceedings of Universities. Applied Chemistry and Biotechnology. 2017;7(1)(10):119–126. (In Russ.).
  21. Kalenik TK, Kravchenko MV, Grishchenko VV, Yanguo S, Lyakh VA. Enriched protein products of marine origin like the new components of the diet for people with physical load. Foods and Raw Materials. 2013;1(1):82–87.
How to quote?
Volkov VV, Mezenova OYa, Moersel J-T, Kuehn S, Grimm T, Hoehling A, et al. Hydrolysis products from sockeye (Oncorhynchus nerka L.) heads from the Kamchatka Peninsula produced by different methods: biological value. Foods and Raw Materials. 2021;9(1):10–18.
About journal