Aarhus University Seal / Aarhus Universitets segl

Digestibility of seaweed protein from Ulva sp. and Saccharina latissima in rats

Publikation: Bidrag til tidsskrift/Konferencebidrag i tidsskrift /Bidrag til avisTidsskriftartikelForskningpeer review


Seaweed is gaining attention as a sustainable source of protein. However, the nutritional protein quality needs further investigation to explore the potential of seaweed as a protein source. This study evaluates in vivo digestibility of six different seaweed protein products, four from Ulva sp. and two from Saccharina latissima. Ulva sp. was either preserved in a preservation liquid and spin flash-dried, freeze-dried without any pre-treatment or protein was extracted from the crude biomass with a screw press and isoelectrically precipitated (pH 2.5) with or without sulfite addition during extraction. Saccharina latissima was either freeze-dried or fermented with lactic acid bacteria prior to freeze-drying. The digestibility of the seaweed products was tested in a rat trial, where seaweed protein products constituted 50% of the nitrogen (N) in diets, the other 50% of N coming from whey protein concentrate. The protein concentration and proportion of essential amino acids (EAA) were increased upon protein extraction from Ulva sp. and the ash content was reduced. This led to an increased N digestibility of 55.5 ± 2.7% for the protein extract without sulfite, being 10–13%-points higher than for the other Ulva sp. products. The sulfite addition seemed to counteract the effect of extraction regarding the N digestibility. Fermentation of S. latissima increased the total amino acid content along with increased EAA proportion and lowered the ash content. However, the fermentation did not improve the organic matter, ash or N digestibility. Digestibility was in general low, but this study demonstrates the potential to increase seaweed N digestibility by more than 20% through protein extraction.

TidsskriftAlgal Research
StatusUdgivet - apr. 2022

Bibliografisk note

Funding Information:
The study was funded by Centre for Circular Bioeconomy at Aarhus University and GUDP , j. no 34009-19- 1615.

Funding Information:
The authors would like to thank Nordisk Tang for providing S. latissima, fermentation of S. latissima and preservation of Ulva, and a thanks to Danish Marine Protein for spin flash drying of the preserved Ulva. Thanks to HedeDanmark for harvesting of the 10 tons Ulva and to Skive Municipality for supporting the project with a site for harvest. The authors would further like to thank Arla Foods Ingredients Group P/S for providing samples of Lacprodan DI-8090. Thanks to Anders Hauer M?ller, Hanne S?nderg?rd M?ller, Per Kristiansen and Torben H. Laursen for assistance during pilot scale extraction. The picture of the rat in the graphical abstract was retrieved from Colourbox. The study was funded by Centre for Circular Bioeconomy at Aarhus University and GUDP, j. no 34009-19- 1615.

Publisher Copyright:
© 2022 The Authors

Se relationer på Aarhus Universitet Citationsformater

ID: 258245854