Comparative interfacial in vitro digestion of protein and polysaccharide oil/water films

PIZONES RUIZ-HENESTROSA, VICTOR M.; PILOSOF, ANA M. R.; BELLESI, FERNANDO A.; DEL CASTILLO SANTAELLA, TERESA; MALDONADO-VALDERRAMA, JULIA

COLLOIDS AND SURFACES B-BIOINTERFACES

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2018 vol. 161 p. 547 - 554

0927-7765

The behaviour of proteins (b-lactoglobulin (blg) and soy protein isolate (SPI)) and a surface active polysaccharide (hydroxypropylmethylcellulose, HPMC) o/w interfacial films under simulated gastrointestinal conditions using the interfacial tensiometer Octopus were compared and related to the performance ofthe emulsions (using the same emulsifiers) under in vitro digestion.The evolution of interfacial tension was used to investigate the effect of gastrointestinal fluids on o/w interfacial films. Clear differences were observed among these emulsifiers. During the gastric phase, HPMC showed the lowest change in interfacial tension values as compared to protein films. The most important changes occurred during the intestinal stage where it was observed an important decrease of interfacial tension associated with therapid penetration of BS, followed by a lower rate of decrease attributable to the accumulation of FFA at the interface. In the last stage, the subphase was exchanged by buffer alone, to remove the reversibly adsorbed digestion products. SPI formed the most resistant interface to the remotion of digestion products, followed by HPMC and finally by blg. The results agree with the degree of lipolysis reported for the emulsions stabilized by these emulsifiers, which suggest that lipid digestion could be modulated by the ability of emulsifiers to prevent the BS activity (to adsorb at the O/W interface or remove the inhibitory digestion products from the interface). Thus, emulsifiers-BS interactions appears as a key factor in controlling the lipolysis.