Continuous production of dilute to dense food grade emulsions via vapor condensation on films.

Dynamic forces between emulsified water drops coated with Poly-Glycerol-Poly-Ricinoleate (PGPR) in canola oil

The preparation of fine and monodispersed water-in-oil (W/O) emulsions by utilizing hydrophobic hollow polypropylene fibers with 0.4 mm pores was investigated in this work. The experiments were carried out using demineralized water as the disperse phase, mineral oil Velocite No. 3 as the continuous phase, and polyglycerol polyricinoleate (PGPR 90) in the concentration range of 2.5 - 10 wt % as the oil-soluble emulsifier. The size of the water droplets in the prepared emulsions and the droplet size distribution strongly depend on the content of the disperse phase, the transmembrane pressure difference, and the emulsifier concentration. Stable emulsions with a very narrow droplet size distribution and a mean droplet diameter lower than 0.27 ?m were produced using 10 wt % PGPR 90 at a pressure difference below 30 kPa.

In this study, the effects of sodium caseinate (NaCN; emulsifier) concentration, a type of hydrophilic emulsifier, as well as concentration of primary W/O emulsion on the stability of water–oil-water (W/O/W) emulsions were investigated. Emulsions were made using two different emulsification techniques including ultrasonic liquid processing and high pressure homogenization (HPH). Microscopy images of W/O/W emulsions in combination with droplet size analysis and viscosity measurements showed that the sample with a higher percentage of primary W/O emulsion (50 wt% vs. 40 wt% and 25 wt%) was more resistant to coalescence (narrower droplet size distribution and lower creaming index). The higher stability of this emulsion at 50 wt% is due to the enhancement in the solution viscosity which slows down the coalescence and destabilization kinetics. The increase in the NaCN concentration from 0.3 wt% to 0.9 wt% (based on total weight of emulsion) led to formation of larger droplets possibly due to the destabilization of primary W/O emulsion through the disruption of polyglycerol polyricinoleate (PGPR) layer. Regarding the effect of emulsifier type, incorporation of Cremophor EL and Tween 60 in comparison with NaCN resulted in formation of smaller droplet size due to their enhanced surface activity at the interface. Finally, we found that using high pressure homogenizer (HPH) instead of ultrasonic processor was detrimental to the emulsion stability and size distribution. These findings further provide new pathways to design emulsion systems for food and drug delivery applications.

Premix membrane emulsification for the preparation of curcumin-loaded nanoemulsions

The ability of food grade aqueous surfactant solutions to remove toluene or 1,2,4-trichlorobenzene entrapped in sand and two Iowa soils was evaluated in batch and column experiments. Also, the effects that environmental conditions have on contaminant solubilization and mobilization by surfactants and the technical viability of recovering the surfactants for possible reuse were studied. Synergism between the anionic Dowfax 8390 and the nonionic T-Maz 60 was not observed. A mixture of the two was less effective than Dowfax 8390 by itself. 1,2,4-trichloroben2ene removal enhancements via microemulsifiers were less effective than that by Dowfax 8390 for a sandy soil. Food grade surfactants were suitable for surfactant-aided remediation of Fruitfield Iowa soils contaminated with toluene or 1,2,4-trichlorobenzene. Based on the experimental results, optimal range for each environmental parameters was: 1) Surfactant solution pH: 10, 2) Surfactant solution concentration; 4%(v/v), 3) Surfactant solution average temperature: 33.4°C, 4) Surfactant solution flow rate: 4mL/min, 5) Surfactant solution volume to soil weight ratio: 4. The removal of 95% of 1,2,4-trichlorobenzene was obtained with optimal conditions. In addition, surfactant-assisted saturated hydraulic conductivity losses were observed experimentally and should be considered prior to in-situ surfactant remediation. Counter-current solvent extraction was investigated to determine its efficiency for used surfactant recovering. A simple counter-current extraction apparatus with a convex orifice system was used. Hexane, acetone, and methylene chloride were used as the counter-current solvent. Toluene was effectively removed from the anionic surfactant solution using methylene chloride solvent and 1,2,4trichlorobenzene was effectively removed from the anionic surfactant solution using hexane or methylene chloride. Removal of toluene was greatest at 30ml-/min of methylene chloride flow rate and 1,2,4-trichlorobenzene was greatest at 10mL/min of hexane flow rate. This study suggests that counter-current solvent extraction methods may help to recycle anionic surfactant solutions used for remediation of contaminated soil and groundwater.

The formation of double emulsions in skim milk using minimal food-grade emulsifiers – A comparison between ultrasonic and high pressure homogenisation efficiencies

Preparation of water-in-oil-in-water (W1/O/W2) double emulsions containing trans-resveratrol

Two hydrophobic porous ethylene-chlorotrifluoroethylene (ECTFE) membranes quenched in water and air were fabricated by thermally induced phase separation and used for water recovery from ammonia-containing humid gas via vapor condensation. The ECTFE membranes were further hydrophobically modified to enhance their condensation performance. The condensate water quality of the modified membrane significantly improved. The mechanisms of the NH3 contamination in the condensate water were discussed. Surface hydrophobic modification slightly increased the flux and recovery stabilities of the membranes. However, the modification also increased the membrane surface roughness, which adversely affects the vapor condensation and droplet evolution on the membrane surface and reduced the recovered water quality. From the material perspective, desirable porous membranes for vapor condensation should have high surface hydrophobicity and smoothness and reasonably large pore sizes. The reasonably large pore sizes would promote noncondensable gaseous contaminants (e.g., ammonia) to go through the membrane, thereby improving the recovered water quality.

Pomegranate peel is an agro-industrial waste that can be used as source of punicalagin, a polyphenolic compound with several beneficial effects on health. Since, once extracted, punicalagin is prone to degradation, its encapsulation by double emulsions can be an alternative to protect the active compound and control its release. The aim of this investigation was to evaluate the feasibility of encapsulating pomegranate peel extract (PPE) in double emulsions using different types of oils (castor, soybean, sunflower, Miglyol and orange) in a ratio of 70:30 (oil:PPE) and emulsification methods (direct membrane emulsification and mechanical agitation), using polyglycerol polyricinoleate (PGPR) and Tween 80 as lipophilic and hydrophilic emulsifiers, respectively. Direct membrane emulsification (DME) led to more stable emulsions during storage. Droplet size, span values, morphology and encapsulation efficiency (EE) were better for double emulsions (DEs) prepared by DME than for mechanical agitation (MA). DEs formulated using Miglyol or sunflower oil as the oily phase could be considered as suitable food grade systems to encapsulate punicalagin with concentrations up to 11,000 mg/L of PPE.

Water-in-oil-in-water (W1/O/W2) double emulsions stabilized by polyglycerol polyricinoleate (PGPR), a lipophilic food grade small polymer, and sodium caseinate, a hydrophilic milk protein, were developed to encapsulate vitamin B12, a model hydrophilic substance easy to titrate. Using rheology, sensitive to drop size evolution and water fluxes, static light scattering, and microscopy both giving the evolution of drops' size and vitamin B12 titration assessing the encapsulation, we were able to detect independently the double emulsion drop size, the encapsulation loss, and the flux of water as a function of time. By differentiating the PGPR required to cover the W1-droplets' surface from PGPR in excess in the oil phase, we built a PGPR-inner droplet volume fraction diagram highlighting the domains where the double emulsion is stable toward encapsulation and/or water fluxes. We demonstrated the key role played by nonadsorbed PGPR concentration in the intermediate sunflower oil phase on the emulsion stability while, surprisingly, the inner droplet volume fraction had no effect on the emulsion stability. At low PGPR concentration, a release of vitamin B12 was observed and the leakage mechanism of coalescence between droplets and oil-water interface of the oily drops (also called globules hereafter), was identified using confocal microscopy. For high enough PGPR content, the emulsions were stable and may therefore serve as efficient capsules without need of an additional gelling, thickening, complexion or interface rigidifying agent. We generalized these results with the encapsulation of an insecticide: Cydia pomonella granulovirus used in organic arboriculture.

Aim: In this study, self-emulsifying drug delivery system (SEDDS) for oral delivery of opioid peptide dalargin were developed and characterized in vitro. Methods: Dalargin lipophilicity was increased by O-esterification of tyrosine OH group, hydrophobic ion pairing, or a combination thereof. Distribution coefficients (log D) of lipidized dalargin derivatives were determined. Then, dalargin was incorporated in chosen SEDDS, namely SEDDS-1, composed of 50% Capmul 907, 40% Cremophor EL, and 10% propylene glycol and comparatively more lipophilic SEDDS-2 composed of 30% Captex 8000, 30% Capmul MCM, 30% Cremophor EL, and 10% propylene glycol. Additionally, SEDDS were characterized regarding droplet size, polydispersity index (PDI), cloudy point, physical stability and stability against pancreatic lipase. Furthermore, mucus permeating properties of SEDDS and their ability to protect the incorporated dalargin against proteolysis by trypsin, α-chymotrypsin, elastase, simulated gastric fluid (SGF), and simulated intestinal fluid (SIF) were evaluated. Results: The highest dalargin drug payload of 4.57% in SEDDS-2 was achieved when dalargin palmitate (pDAL) was ion paired with sodium dodecyl sulfate (SDS) in molar ratio 1:1. Moreover, SEDDS-1 and SEDDS-2 had a narrow droplet size distribution with average droplet sizes of 42.1 and 33.1 nm with PDI of 0.042 and 0.034, respectively. Lipolysis study showed that within 30 min 78.5% of SEDDS-1 and 92.1% of SEDDS-2 were digested. In addition, both SEDDS exhibited mucus permeating properties as well as a protective effect against enzymatic degradation by trypsin, α-chymotrypsin, elastase, SGF and SIF. Conclusion: The results of this study suggest that the developed SEDDS could be considered for oral opioid peptide delivery.

Using the experimental design methodology, we have developed and characterized nanoemulsions for a parenteral delivery using diazepam as a model drug. The formulations containing 20 or 30% (w/w) of medium chain triglycerides or the mixture of medium chain triglycerides and soybean oil as the oil phase, soybean lecithin and polysorbate 80 as emulsifiers, and a phosphate buffer solution as the aqueous phase were prepared by cold high pressure homogenization. The obtained nanoemulsions were evaluated in terms of droplet size, size distribution, surface charge, drug-vehicle interactions and physical stability. To evaluate the effects of the oil phase type, oil content and drug presence, as well as their interactions on critical quality attributes of nanoemulsions, a three-factor two-level full factorial design was applied. After the preparation, all nanoemulsions revealed small spherical droplets in the range 170-210 nm, with the narrow droplet size distribution ( lt 0.15) and the surface charge about -60 mV. The experimental design results indicated that not only factors alone (oil type, oil content, presence of drug), but their interactions also had a significant effect on the nanoemulsion droplet size, polydispersity index, and zeta potential. During two months of storage at 25°C, all nanoemulsions formulated with the medium chain triglycerides-soybean oil mixture (4:1, w/w) remained physically stable, without considerable changes in monitored parameters. Physicochemical characteristics and stability of these nanoemulsions demonstrated their suitability for parenteral drug delivery.

The effect of ethanol added to the natural gas stream on the top of line corrosion: An approach on vapor phase condensation and carbonic acid generation yield

We demonstrate the collective roles of surfactant–triacylglycerol interactions and confined gap shear crystallization on the creation of novel microstructured water-in-oil emulsions containing solid lipid-encapsulated water droplets. The emulsions studied consisted of 20 wt % water dispersed in a mixture of canola oil, a stabilizing fat [hydrogenated canola oil (HCO)] and either glycerol monoleate (GMO) or polyglycerol polyricinoleate (PGPR) as surfactants. Following valve homogenization, emulsions were cooled from 70 to 25 °C either in a stirred beaker (bulk-cooling) or on a rheometer stage (confined gap shear-cooling). Irrespective of the cooling protocol, GMO promoted HCO nucleation at the oil–water interface and later in the continuous phase, providing combined Pickering and network stabilization. With PGPR, HCO nucleated in the continuous phase with little evidence of interfacial nucleation. Bulk-cooling resulted in spherulitic HCO crystalline aggregates, whereas in a confined gap, ellipsoidal crystalline masses (crystal cocoons) were created. The presence of GMO led to the inclusion of the dispersed aqueous phase within these cocoons, whereas with PGPR, no such droplet encapsulation was observed. It is proposed that molecular compatibility between the oleic acid in GMO and the stearic acids in HCO permitted their liquid-state association and thus HCO nucleation and crystallization on the droplet surface, whereas PGPR’s lack of complementarity did not promote such nucleation. The formation of such crystal cocoons enclosing water droplets represents the first instance of this new class of Pickering-type emulsion stabilization.

Ground water contamination frequently consists of mixed chlorinated solvents [e.g., tetrachloroethylene (PCE), trichloroethylene (TCE), and trans-1,2- dichloroethylene (DCE)]. In this research, mixtures of the food grade (edible) surfactants bis(2-ethylhexyl) sodium sulfosuccinate (AOT) and sodium mono- and dimethylnaphthalene sulfonate (SMDNS) were used in the formation of middle-phase microemulsions for mixed chlorinated solvents. Microemulsions of binary (e.g., PCE/TCE, PCE/DCE, DCE/TCE) and ternary (PCE/TCE/DCE) chlorinated solvent systems were evaluated. Several empirical correlations were used for describing and/or predicting the phase behavior of the resulting middle-phase microemulsions (e.g., the ideal mixing rule or the nonideal regular mixing theory). The ideal mixing rule provided a good approximation for binary and ternary systems, but experimental deviations from the predictions were significant enough to affect the optimal surfactant system. Nonideal regular mixing theory demonstrated much ...