scholarly journals Emulsion Formation and Stabilizing Properties of Olive Oil Cake Crude Extracts

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 633
Author(s):  
Firdaous Fainassi ◽  
Noamane Taarji ◽  
Fatiha Benkhalti ◽  
Abdellatif Hafidi ◽  
Marcos A. Neves ◽  
...  
Keyword(s):  
Olive Oil ◽  
Ethanol Extract ◽  
Active Components ◽  
Oil In Water ◽  
Surface Active ◽  
Ph Conditions ◽  
Oil Water ◽  
Surface Active Compounds ◽  
Ionizable Groups ◽  
Emulsifying Ability

The surface-active and emulsifying properties of crude aqueous ethanolic extracts from untreated olive oil cake (OOC) were investigated. OOC extracts contained important concentrations of surface-active components including proteins, saponins and polyphenols (1.2–2.8%, 7.8–9.5% and 0.7–4.5% (w/w), respectively) and reduced the interfacial tension by up to 46% (14.0 ± 0.2 mN m−1) at the oil–water interface. The emulsifying ability of OOC extracts was not correlated, however, with their interfacial activity or surface-active composition. Eighty percent aqueous ethanol extract produced the most stable oil-in-water (O/W) emulsions by high-pressure homogenization. The emulsions had average volume mean droplet diameters of approximately 0.4 µm and negative ζ-potentials of about -45 mV, and were stable for up to 1 month of storage at 5, 25 and 50 °C. They were sensitive, however, to acidic pH conditions (<5) and NaCl addition (≥25 mM), indicating that the main stabilization mechanism is electrostatic due to the presence of surface-active compounds with ionizable groups, such as saponins.

Performance of oil-in-water emulsions stabilized by different types of surface-active components

2020 ◽  
Vol 190 ◽  
pp. 110939 ◽  
Author(s):  
Bruna Barbon Paulo ◽  
Izabela Dutra Alvim ◽  
Gary Reineccius ◽  
Ana Silvia Prata
Keyword(s):  
Active Components ◽  
Oil In Water ◽  
Different Types ◽  
Surface Active

scholarly journals Microemulsion-Based Solid Lipid Nanoparticles As Emulsion Stabilisers

2021 ◽  
Author(s):  
Elham H. Hazfi
Keyword(s):  
Solid Lipid Nanoparticles ◽  
Lipid Nanoparticles ◽  
Continuous Phase ◽  
Tween 20 ◽  
Microemulsion System ◽  
Solid Lipid ◽  
Oil In Water ◽  
Phase Crystal ◽  
Surface Active ◽  
Oil Water

The preparation and properties of water-in-oil (W/O) emulsions stabilised solely by adsorbed surface-active solid lipid nanoparticles (SLNs) at the oil-water interface were studied. Monostearin-based SLNs were prepared using food-grade micoremulsions as nanoscle 'reactors'. Hot oil-in-water (O/W) microemulsions (70°C) consisting of monostearin, Tween 20, ethanol and water were crash-cooled to 4°C to promote the liquid-solid transition of the monostearin and thus develop sub-micron solid lipid particles. SLNs obtained from the cooled microemulsions were partially stabilised with addition to lecithin (0.5% w/w) to the microemulsion system. With 2% (w/w) added monstearin, the W/O emulsion was stable for the 14 days of study. The microstructure of the emulsions revealed the presence of two stabilisation mechanisms, namely Pickering-type and continuous phase crystal network stabilisation, which both contributed to slowing dispersed droplet coalescence. Overall, this study demonstrated that surface-active SLNs developed using a microemulsion technique could effectively kinetically stabilise model W/O emulsions.

scholarly journals Improvement of the Carotenoids Bioaccessibility from Vegetable Salads Using Excipient Emulsions: Impacts of the Emulsification and the Type of Dietary Fats

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 81-81
Author(s):  
Yuanhang Yao ◽  
Darel Wee Kiat Toh ◽  
Yang Kai Chan ◽  
Jung Eun Kim
Keyword(s):  
Olive Oil ◽  
Coconut Oil ◽  
Dietary Fats ◽  
Water Mixture ◽  
Total Carotenoids ◽  
Water Emulsion ◽  
Oil In Water ◽  
Oil Water ◽  
Oil In Water Emulsion ◽  
Β Carotene

Abstract Objectives Carotenoids which are rich in fruits and vegetables, are known for their health-promoting benefits. However, due to their hydrophobicity, carotenoids are poorly absorbed in human body and there is a need to improve their absorption. This study aimed to evaluate the effects of the emulsification and the type of dietary fat on the bioaccessibility of carotenoids from vegetable salads. Methods Oil-in-water emulsions were formed using the high-pressure homogenizer with whey protein isolate as the emulsifier. A mixture of raw vegetable salads, including tomatoes, baby spinach, carrots, romaine lettuce and Chinese wolfberry, were co-digested with 4 different types of dietary fats: olive oil-in-water emulsion (OLE), olive oil-water mixture (OLN), coconut oil-in-water emulsion (COE) and coconut oil-water mixture (CON). The bioaccessibility of 5 main carotenoids (lutein, zeaxanthin, α-carotene, β-carotene and lycopene) was evaluated via a simulated in-vitro gastrointestinal model and the carotenoids were detected by high-performance liquid chromatography. Results The bioaccessibility (mean ± SD) of total carotenoids was enhanced when vegetable salads were co-digested with the oil-in-water emulsion (23.5 ± 2.8%) than the oil-water mixture (15.4 ± 7.6%) (P &lt; 0.05). Specifically, OLE showed an increase in the bioaccessibility of α-carotene (OLE: 24.5 ± 2.4%, OLN: 19.0 ± 0.6%, P &lt; 0.05) and β-carotene (OLE: 20.4 ± 1.0%, OLN: 14.6 ± 2.5%, P &lt; 0.05), compared to OLN, while no differences were observed for lutein, zeaxanthin and lycopene. On the other hand, COE resulted in higher bioaccessibility of all the individual carotenoids as compared to CON (P &lt; 0.05), except for the zeaxanthin. Overall, the bioaccessibility of total carotenoids was higher with olive oil (24.0 ± 2.8%) than coconut oil (14.9 ± 6.9%) (P &lt; 0.05). Conclusions Findings from this study indicate that emulsification of dietary fats and olive oil enhance the bioaccessibility of carotenoids. Using excipient olive oil-in-water emulsion in particular, may be a potential way to improve the absorption of carotenoids when it is added into the carotenoids-rich vegetable salads as salads dressing. Funding Sources National University of Singapore, Agency for Science, Technology and Research.

scholarly journals Improving Stability of Tear Film Lipid Layer via Concerted Action of Two Drug Molecules: A Biophysical View

2020 ◽  
Vol 21 (24) ◽  
pp. 9490
Author(s):  
Petar Eftimov ◽  
Agnieszka Olżyńska ◽  
Adéla Melcrová ◽  
Georgi As. Georgiev ◽  
Philippe Daull ◽  
...  
Keyword(s):  
Dry Eye ◽  
Tear Film ◽  
Eye Drops ◽  
Active Components ◽  
Lipid Film ◽  
Drug Molecules ◽  
Air Interface ◽  
Oil In Water ◽  
Surface Active ◽  
Dynamics Simulations

The tear film at the ocular surface is covered by a thin layer of lipids. This oily phase stabilizes the film by decreasing its surface tension and improving its viscoelastic properties. Clinically, destabilization and rupture of the tear film are related to dry eye disease and are accompanied by changes in the quality and quantity of tear film lipids. In dry eye, eye drops containing oil-in-water emulsions are used for the supplementation of lipids and surface-active components to the tear film. We explore in detail the biophysical aspects of interactions of specific surface-active compounds, cetalkonium chloride and poloxamer 188, which are present in oil-in-water emulsions, with tear lipids. The aim is to better understand the macroscopically observed eye drops–tear film interactions by rationalizing them at the molecular level. To this end, we employ a multi-scale approach combining experiments on human meibomian lipid extracts, measurements using synthetic lipid films, and in silico molecular dynamics simulations. By combining these methods, we demonstrate that the studied compounds specifically interact with the tear lipid film enhancing its structure, surfactant properties, and elasticity. The observed effects are cooperative and can be further modulated by material packing at the tear–air interface.

scholarly journals Microemulsion-Based Solid Lipid Nanoparticles As Emulsion Stabilisers

2021 ◽  
Author(s):  
Elham H. Hazfi
Keyword(s):  
Solid Lipid Nanoparticles ◽  
Lipid Nanoparticles ◽  
Continuous Phase ◽  
Tween 20 ◽  
Microemulsion System ◽  
Solid Lipid ◽  
Oil In Water ◽  
Phase Crystal ◽  
Surface Active ◽  
Oil Water

The preparation and properties of water-in-oil (W/O) emulsions stabilised solely by adsorbed surface-active solid lipid nanoparticles (SLNs) at the oil-water interface were studied. Monostearin-based SLNs were prepared using food-grade micoremulsions as nanoscle 'reactors'. Hot oil-in-water (O/W) microemulsions (70°C) consisting of monostearin, Tween 20, ethanol and water were crash-cooled to 4°C to promote the liquid-solid transition of the monostearin and thus develop sub-micron solid lipid particles. SLNs obtained from the cooled microemulsions were partially stabilised with addition to lecithin (0.5% w/w) to the microemulsion system. With 2% (w/w) added monstearin, the W/O emulsion was stable for the 14 days of study. The microstructure of the emulsions revealed the presence of two stabilisation mechanisms, namely Pickering-type and continuous phase crystal network stabilisation, which both contributed to slowing dispersed droplet coalescence. Overall, this study demonstrated that surface-active SLNs developed using a microemulsion technique could effectively kinetically stabilise model W/O emulsions.

scholarly journals Properties of Isolated Lignin From Model Wastewater

2015 ◽  
Vol 1 ◽  
pp. 282
Author(s):  
Sanita Skudra ◽  
Galia Shulga ◽  
Vadims Shakels ◽  
Lubova Belkova ◽  
Skaidrite Reihmane
Keyword(s):  
Surface Activity ◽  
Emulsion Stability ◽  
Water Emulsion ◽  
Reduced Viscosity ◽  
Surface Active Properties ◽  
Oil In Water ◽  
Surface Active ◽  
Oil Water ◽  
Decreasing Ph ◽  
Oil In Water Emulsion

Model wastewater, imitating the hydrothermal treatment of birch wood in the basins of veneer production, was obtained under laboratory conditions. Birch lignin (BLIG) was isolated from the model wastewater by precipitation with concentarted sulphuric acid. The increase in reduced viscosity with decreasing concentration of BLIG in the water solutions indicated its polyelectrolyte behaviour. The presence of both ionized functional groups and hydrophobic aromatic fragments in the BLIG molecules favoured its surface active properties. With decreasing pH and increasing concentration, the surface activity of BLIG at the air-water and oil-water interfaces increased, indicating the enhanced hydrophobicity of lignin fragments due to the protonization of its acidic groups. The pronounced surface activity of BLIG was in accordance with the very low value of its critical micelle concentration. The dependence of the emulsion stability on the ionic strength may testify the predominant structural mechanical mechanism of the stabilization of the rapeseed oil-in-water emulsion, containing BLIG as a stabilizer. The revealed surface properties of the isolated lignin allow predicting its application for lowering surface tension in different disperse systems to prevent the coalescence and agglomeration phenomena.

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