Compositional properties and bioactive potential of waste material from shrimp cooking juice

- Material from shrimp cooking juice with antioxidant and ACE-inhibitory capacities.
- Compositional properties of a functional concentrate were reported.
- Peptides rich in Gly and Pro were responsible for high ACE-inhibitory capacity.
- Free astaxanthin and derived esters were detectable in the cooking juice.

A functional concentrate rich in proteins and lipids was obtained from an industrial shrimp cooking juice by using a centrifugal separator, and it was characterized in terms of chemical composition parameters and functional or biological activity (antioxidant and ACE-inhibitory capacities). The concentrate presented 116 g/kg protein, 135 g/kg crude fat and ash content less than 10 g/kg, with predominance of Na ions, followed by K, Ca, Mg, Cu, Fe, Zn and Mn. A relative abundance of glucose, glycerol, polyalcohols, acetate and phosphate was found. The antioxidant (as determined by ABTS, FRAP, chelating and photoluminescence assays) and ACE-inhibitory capacities of the material recovered from the shrimp cooking juice were strongly related to the presence of small peptides (1355-502 Da), with a clear predominance of Gly, Pro, Glu, Asp and Arg. Other antioxidants, such as free astaxanthin (cis and trans isomers) and derived esters, were also detected.