Properties and stability of oil-in-water emulsions stabilized by microfibrillated cellulose from mangosteen rind

The influence of concentration of microfibrillated cellulose (MFC) extracted from mangosteen (Garcinia mangostana L.) rind on the properties and stability of 10% w/w soybean oil-in-water (o/w) Pickering emulsions (pH ≈ 7.0) was examined. The MFC concentration in the aqueous phase was varied from 0.05 to 0.70% w/w. The mean droplet size and the color intensity of the emulsions increased with increasing MFC concentration. Microscopic observations revealed that the MFC particles mainly adsorbed at the oil-water interface of the emulsion droplets, whereas the amount of excess non-adsorbing MFC particles present in the continuous aqueous phase increased with increasing MFC concentration. The rheological data provided evidence for network formation in the emulsions with increasing MFC concentration. Such a gel-like behavior was attributed to an inter-droplet network structure and the formation of an MFC network in the continuous phase. All the emulsions were stable to coalescence for a period of 80 days whatever the MFC concentration but the stability to creaming decreased progressively with decreasing MFC concentration. These results have important implication for the rational design and production of particle-stabilized food emulsions.