Aquafeed ingredient production from herring (Clupea harengus) by-products using pH-shift processing: Effect from by-product combinations, protein solubilization-pH and centrifugation force
Journal article, 2019

There is a strong need in animal production for sustainable protein sources used in feed. The aim of the present study was to evaluate the potential of the pH-shift process as a method to concentrate proteins from complex bone-rich herring (Clupea harengus) by-products. By-product parts (frame, head, guts), protein solubilization pH (pH 2.8 or 11.3) and separation g-force (800 or 8000 g) were varied. The findings revealed that protein recovery yields of up to 60% were obtained and that higher protein yield was obtained from the alkaline than the acid process. By-product part and g-force had no significant impact on protein yield. Protein levels reached in the concentrates were 75–80 % (dw basis). Protein concentrates contained a similar amino acid profile as have been reported for fishmeal, with ~40% essential amino acids and up to 7.8% and 2.8% of lysine and methionine. Residual levels of LC n-3 PUFA as well as calcium, magnesium, potassium and phosphorous were also found in the produced protein concentrates which could be an added value. Acid produced concentrates were particularly high in calcium potassium and phosphorous. Provided a careful evaluation, the pH-shift process could become a successful alternative to classic fish meal production for increasing the use of fish by-products for production of protein ingredients for feed.

HerringClupea harenguspH-shift processProteinFishmealBy-productFeed


James Hinchcliffe

University of Gothenburg

Nils-Gunnar Carlsson

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Elisabeth Jönsson

University of Gothenburg

Kristina Sundell

University of Gothenburg

Ingrid Undeland

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Animal Feed Science and Technology

0377-8401 (ISSN)

Vol. 247 273-284

Förädling av ryggben från sill till högvärdig livsmedelsingrediens

Västfem AB (Förädling-stöd), 2018-08-28 -- 2020-03-31.

Swedish Board of Agriculture (2017-4683), 2018-08-28 -- 2020-03-31.

Development of NOvel, high‐quality MArine aquaCULTURE in Sweden ‐ with focus on environmental and economic sustainability (NOMACULTURE)

The Swedish Foundation for Strategic Environmental Research (Mistra) (2013/75), 2014-06-01 -- 2018-08-31.

Subject Categories

Food Science

Fish and Aquacultural Science



More information

Latest update