In this test, scientists wanted to assess the emulsifying and anti-oxidant properties of FPH (fish protein hydrolysates). The idea was to check the physical and the oxidative stabilization of five percent fish oil (FO) in water emulsions. In this test, researchers took muscle proteins from Sardines and Small Spotted Catshark. They hydrolyzed (broke down) the proteins to DH (degrees of hydrolysis) of 3-4-5-6 percent with the protein-digesting enzyme, subtilisin.
Sardine hydrolysates, where there was a low degree of hydrolysis (3-4 percent), showed the most effectual peptides to physically steady emulsions with the tinier droplet sizes. This indicated that more protein adsorbed at the interface to act as a protective barrier against pro-oxidants. This detail might be responsible for the higher oxidative steadiness of these emulsions. In those hydrolysates that the researchers prepared from the Small Spotted Catshark, only the hydrolysate with degrees of hydrolysis three percent produced a physically-stable blend with lower concentration of the unsaturated aldehydes.
The conclusions show the potential for fish protein hydrolysates (FPH) as another possible protein emulsifier for the creation of oxidatively-stable FO-in-water emulsions.
Resource
Physical and oxidative stability of fish oil-in-water emulsions stabilized with fish protein hydrolysates.