Physical Stability Of Oil-In-Water Emulsion Stabilized By Gelatin From Saithe (Pollachius Virens) Skin

The objective of the present study was to investigate the physical stability of an oil-in-water (O/W) emulsion stabilized with gelatin from saithe (Pollachius virens) skin obtained with three different extraction protocols compared to two commercial fish skin gelatins. We first investigated the gelatin powder composition, and then produced the O/W emulsions at pH 3 by mechanical dispersion followed by an ultrasonication process. Sodium dodecyl sulfate (SDS) profiles for commercial samples indicated that extensive and unspecific hydrolysis of collagen occurred during the production process, whereas gelatin extracted from saithe fish skin showed typical electrophoresis patterns of type I collagen, with the presence of gamma- and beta-chains. Emulsions obtained with commercial samples presented high physical stability over 7 days, with particle size of similar to 200 nm. However, emulsions obtained with saithe fish skin presented particle size between 300 and 450 nm. Slight differences were observed in viscosity, with values between similar to 1 and similar to 4 mPa center dot s. Interfacial tension measurements presented values between 13 and 17 mN center dot m(-1) with three different regimes for all the systems.