Novel starch based emulsion gels and emulsion microgel particles: Design, structure and rheology

Abstract

Novel starch-based emulsion microgel particles were designed using a facile top-down shear-induced approach. The emulsion droplets were stabilized using octenyl succinic anhydride (OSA) modified starch and incorporated into heat-treated and sheared native starch gels, forming emulsion gels. Using gelation kinetics and small deformation rheological measurements of sheared native starch gels and emulsion gels, OSA starch-stabilized emulsion droplets were demonstrated to act as "active fillers". By varying native starch concentrations (15-20wt%) and oil fractions (5-20wt%), optimal concentrations for the formation of emulsion microgel particles were identified. Microscopy at various length scales (transmission confocal laser scanning and cryo-scanning electron microscopy) and static light scattering measurements revealed emulsion microgel particles of 5-50μm diameter. These novel emulsion microgel particles created via careful combination of gelatinized native starch and OSA stabilised-emulsion droplets acting as active fillers may find applications in food and personal care industries for delivery of lipophillic molecules.

Composite whey protein–cellulose nanocrystals at oil-water interface: Towards delaying lipid digestion

“…Although W1C3 also showed a small degree of 334 coalesced droplets in presence of pancreatin and bile salts, the majority of the 335 population of emulsion droplets were the ones coated by CNC (10-30 µm) that 336 appeared to retain the microstructural intactness. A closer look at these CNC-coated 337 droplets in case of W1C1 and W1C3 revealed that these were actually not individual 338 droplets coated by CNC, but were rather several small emulsion droplets bridged 339 together in a "raspberry-like" floc, resembling emulsion microgel particles (Torres,340 Murray, & Sarkar, 2016Torres, Tena, Murray, & Sarkar, 2017). This indicates 341 that this relatively large fraction of droplets, which were rather encapsulated by and 342 within a CNC particulated layer (3 wt%) might not have had direct access to be 343 cleaved by the enzymes and thus the coalescence was rather diminished in case of 344 W1C3 (Figure 4).…”

Overcoming in vitro gastric destabilisation of emulsion droplets using emulsion microgel particles for targeted intestinal release of fatty acids

“…Emulsion microgel particles are a relatively new class of "smart" soft solid vehicles where several emulsion droplets are encapsulated within a biopolymer hydrogel particle (Torres, Murray, & Sarkar, 2016, 2017Torres, Reyes, Murray, & Sarkar, 2018;Torres, Tena, Murray, & Sarkar, 2017). This structure offers several advantages over conventional O/W emulsions.…”

Effect of cooking on glycemic index, antioxidant activities, α‐amylase, and α‐glucosidase inhibitory properties of two rice varieties

“…Gelatinized starch is not thermodynamically stable, hence a progressive re‐association of the starch molecules upon cooling (Torres, Tena, Murray, & Sarkar, 2017). This recrystallization is referred to as retrogradation and may be responsible for the apparent increase in the starch content after cooking (Garcia‐Alonso, Jimenez‐Escrig, Martin‐Carron, Bravo, & Saura‐Calixto, 1999).…”

“…Furthermore, the apparent increase in the starch content of the rice grains after cooking could be due to retrogradation. Gelatinized starch is not thermodynamically stable, hence a progressive reassociation of the starch molecules upon cooling (Torres, Tena, Murray, & Sarkar, 2017). This recrystallization is referred to as retrogradation and may be responsible for the apparent increase in High level of amylose in food products has been related to low blood glucose in comparison with high amylopectin food products.…”