There is increasing interest in the development of Coenzyme Q10 (CoQ10) ingredients appropriate for functional food formulations, due to its potential health effects. The present work reported that food proteins including milk and soy proteins can effectively perform as vehicles to remarkably improve water dispersibility, stability and even bioaccessibility of CoQ10. The improvement was mainly due to the formation of protein-CoQ10 complexes, through hydrophobic interactions. The formation of complexes with CoQ10 distinctly changed the physicochemical properties of food protein particles that seemed to be more favorable for their colloidal stability. The complexation remarkably improved the stability against UV exposure or in vitro digestion, and bioaccessibility of CoQ10. In contrast, milk proteins (sodium caseinate and whey protein concentrate) were more appropriate to perform as vehicles for improved bioaccessibility of CoQ10 than soy protein isolate. The findings provide an effective strategy to improve the delivery and bioaccessibility of CoQ10 for the formulation of functional foods enriched with CoQ10.

In most publications concerning edible W/O/W-emulsions, the low-HLB emulsifier polyglycerol polyricinoleate (PGPR) is used to stabilize the W/O-interface in combination with a high-HLB emulsifier which stabilizes the O/W-interface. Therefore, PGPR was used as the reference low-HLB emulsifier and compared to two alternative low-HLB emulsifiers namely ammonium phosphatide (AMP) and low-HLB sucrose ester O-170. As high-HLB emulsifiers both random coil (sodium caseinate) and globular proteins (whey protein isolate) were used. Hereby, the use of WPI led to similar, high enclosed water volume fractions for all used low-HLB emulsifiers whereas the use of Na-Caseinate led to almost no enclosed water in the emulsions containing ammonium phosphatide. Finally, the influence of osmotic pressure gradients on the release of an enclosed compound was examined. Therefore, the W/O/W-emulsions were diluted in iso-, hypo- and hypertonic solutions after which the release of an enclosed marker compound was followed over time. Hereby, AMP- and O-170 stabilized W/O/W-emulsions released the enclosed marker due to swelling under hypotonic dilution whereas hyper- and isotonic dilution never led to release of the enclosed marker, regardless of the used low-HLB emulsifier.

We designed Air-in-Oil-in-Water (A/O/W) emulsions. First, Air-in-Oil foams were fabricated by whipping anhydrous milk fat. The maximum overrun was obtained at 20 °C. The foams contained 30–35 vol% air and were stabilized solely by fat crystals. To refine the bubble size, foams were further sheared in a Couette’s cell. The average bubble size reached a value as small as 6.5 μm at a shear rate of 5250 s−1. The nonaqueous foams were then dispersed in a viscous aqueous phase containing sodium caseinate to obtain A/O/W emulsions. The shear rate was varied from 1000 to 7500 s−1, allowing to obtain Air-in-Oil globules whose average diameter ranged from 15 to 60 μm. To avoid globule creaming, the aqueous phase was gelled by incorporating hydroxyethyl cellulose. Homogeneous emulsions were obtained with fat globules containing around 22 vol% of residual air. The systems were kinetically stable for at least 3 weeks at 4 °C.

This work is part of the Strategic Research Programme 2011-2016 and is funded by the Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS). | Peer reviewed

The aim of this study was to compare the efficiency of three different food‐grade emulsifiers to form and stabilise an orange oil‐in‐water emulsion. The emulsifier type and concentration had a profound effect on the initial particle size of the oil droplets with Tween 80 being the most effective in reducing the particle size (1% w/w, 1.88 ± 0.01 μm) followed by sodium caseinate (10% w/w, 2.14 ± 0.03 μm) and gum arabic (10% w/w, 4.10 ± 0.24 μm). The long‐term stability of the concentrated beverages was monitored using Turbiscan analysis. The Turbiscan stability indices after 4 weeks of storage followed the order: Tween 80 (1.70 ± 0.08) < gum arabic (4.83 ± 0.53) < sodium caseinate (6.20 ± 1.56). The protein emulsifier was more capable to control the oxidation process, and this was attributed to the excess amount of emulsifier present in the aqueous phase. This study provides useful insights into the formulation of flavour emulsions by the beverage industry.