A feeding study to assess nutritional quality and safety of surimi wash water proteins recovered by a chitosan-alginate complex

Soluble proteins from surimi wash water (SWW) precipitated using a chitosan-alginate (Chi-Alg) complex and recovered by centrifugation were freeze-dried. Analysis showed that SWW proteins (SWWP) had a crude protein content of 73.1% and a high concentration of essential amino acids, for example, 3% histidine, 9.4% lysine, 3.7% methionine, and 5.1% phenylalanine. In a rat-feeding trial, SWWP as a single protein source showed higher (P < 0.05) modified protein efficiency ratio and net protein ratio than the casein control. Blood chemistry analysis revealed no deleterious effect from the full protein substitution or the chitosan in SWWP. Therefore, this preliminary study revealed that proteins recovered from SWW using the Chi-Alg complex could be used in feed formulations. They could be used for food production in countries where regulatory agencies allow the use of chitosan in the production of food ingredients.