Abstract
Water-in-oil high internal phase emulsions (HIPEs) can provide interesting textures that could be used to reduce trans- and/or saturated fat content in food products. On the other hand oil-in-water emulsions can be found in a variety of food and beverages. Moreover, strategies aiming synthetic or semi-synthetic ingredients replacement by natural alternatives for food applications has been pursuit. For these purposes, the effect of partial replacement of PGPR by lecithin on properties of either W/O-HIPEs or O/W emulsions manufactured from the same initial composition but showing different volume fraction of dispersed phase were investigated aiming to understand the behaviour of emulsifiers' mixture in water-oil or oil-water interfaces. Firstly, water-in-oil HIPEs were produced using a rotor-stator device. At fixed total amount of emulsifier (2% w/w), W/O emulsions stabilized with LEC:PGPR ratios of 0.5:1.5 and 1.0:1.0 showed similar droplet size with a better kinetic stability compared to emulsions containing only PGPR. These results indicated good interaction between LEC and PGPR, which was also confirmed by dynamic interfacial tension profile and interfacial dilational rheology. In order to reduce the droplet size of W/O-HIPEs, these emulsions were subsequently subjected to high-pressure homogenization and interestingly phases inversion was observed. Confocal microscopy confirmed the phases inversion attributed to high input of energy leading to the formation of O/W emulsions. Then both W/O-HIPEs and O/W emulsions were investigated regarding LEC:PGPR mixtures as emulsifiers. All W/O-HIPEs showed shear thinning behavior and high viscosity at low shear rate whereas O/W emulsions showed low viscosity and Newtonian behavior. The increase of lecithin content in emulsifier mixture led to more stable O/W emulsions, whereas more stable W/O-HIPEs were produced by lecithin and PGPR mixtures ratio of 0.5:1.5 and 1.0:1.0.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.