Physicochemical properties of African catfish mucus and its effects on the stability of soya milk emulsions

Abstract

Mucus, a waste product produced when African catfish undergoes stress, has lubricating effects and could be a potential emulsifier. Emulsions are thermodynamically unstable; researchers have documented synthetic bio-polymers as emulsifiers, but its sustainability is in question. This research aims to establish some physicochemical properties of African catfish mucus (ACM) and its effect in soya milk emulsions. A Zetasizer and Turbiscan were used to measure stability, morphology was determined with Transmission electron microscopy (TEM), while functional groups in ACM and ACM-stabilized soya milk emulsions were determined using Attenuated Total Reflection Fourier Transform Infra-red spectroscopy. ACM is a stable hydrogel with negatively charged (􀀀36.2 mV) loosely bound electrons with polar and non-polar portions. ACM concentrations of 1, 3, and 5 g w/w stabilized soya milk emulsions after 180 min of storage. The spectra of stabilized emulsion revealed interactions with soya milk droplets. ACM encapsulated the stabilized emulsion and conferred a kind of cohesive interaction and stability. Turbiscan revealed that the mucin formed strong cohesive connections with stabilized emulsions and the mucin exhibited adhesive properties. ACM is an excellent natural emulsifier with mucoadhesive properties as it encapsulates soya milk to enhance stability.