Effects of droplet size on the interfacial concentrations of antioxidants in fish and olive oil-in-water emulsions and nanoemulsions and on their oxidative stability

Reports on the effect of droplet size on the oxidative stability of emulsions and nanoemulsions are scarce in the literature and frequently contradictory. Here, we have employed a set of hydroxytyrosol (HT) esters of different hydrophobicity and fish oil-in-water emulsified systems containing droplets of different sizes to evaluate the effect of the droplet size, surfactant, (ΦI) and oil (ΦO) volume fractions on their oxidative stability. To quantitatively unravel the observed findings, we employed a well-established pseudophase kinetic model to determine the distribution and interfacial concentrations of the antioxidants (AOs) in the intact emulsions and nanoemulsions. Results show that there is a direct correlation between antioxidant efficiency and the concentration of the AOs in the interfacial region, which is much higher (20–200 fold) than the stoichiometric one. In both emulsified systems, the highest interfacial concentration and the highest antioxidant efficiency was found for hydroxytyrosol octanoate. Results clearly show that the principal parameter controlling the partitioning of antioxidants is the surfactant volume fraction, ΦI, followed by the O/W ratio; meanwhile, the droplet size has no influence on their interfacial concentrations and, therefore, on their antioxidant efficiency. Moreover, no correlation was seen between droplet size and oxidative stability of both emulsions and nanoemulsions.

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Effect of Droplet Size on the Oxidative Stability of Soybean Oil TAG and Fish Oil TAG in Oil-in-Water Emulsion

Journal of Oleo Science ◽

10.5650/jos.58.329 ◽

2009 ◽

Vol 58 (6) ◽

pp. 329-338 ◽

Cited By ~ 24

Author(s):

Goki Azuma ◽

Naoko Kimura ◽

Masashi Hosokawa ◽

Kazuo Miyashita

Keyword(s):

Fish Oil ◽

Soybean Oil ◽

Oxidative Stability ◽

Droplet Size ◽

Water Emulsion ◽

Oil In Water ◽

Oil In Water Emulsion

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Assessment of Oxidative Stability in Fish Oil-in-Water Emulsions: Effect of Emulsification Process, Droplet Size and Storage Temperature

Journal of Food Process Engineering ◽

10.1111/jfpe.12316 ◽

2015 ◽

Vol 40 (1) ◽

pp. e12316 ◽

Cited By ~ 6

Author(s):

Marcos A. Neves ◽

Zheng Wang ◽

Isao Kobayashi ◽

Mitsutoshi Nakajima

Keyword(s):

Fish Oil ◽

Oxidative Stability ◽

Droplet Size ◽

Storage Temperature ◽

Oil In Water ◽

And Storage ◽

Emulsification Process

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Physical and oxidative stability of functional olive oil-in-water emulsions formulated using olive mill wastewater biophenols and whey proteins

Food & Function ◽

10.1039/c5fo01269d ◽

2016 ◽

Vol 7 (1) ◽

pp. 227-238 ◽

Cited By ~ 23

Author(s):

Nicola Caporaso ◽

Alessandro Genovese ◽

Róisín Burke ◽

Catherine Barry-Ryan ◽

Raffaele Sacchi

Keyword(s):

Oxidative Stability ◽

Olive Oil ◽

Whey Protein ◽

Xanthan Gum ◽

Whey Proteins ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Olive Mill Wastewater ◽

Oil In Water ◽

Olive Mill

Olive oil-in-water emulsions were formulated by adding phenolic extracts from olive mill wastewater, whey protein isolate and xanthan gum.

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Stabilization and Release of Palm Tocotrienol Emulsion Fabricated Using pH-Sensitive Calcium Carbonate

Foods ◽

10.3390/foods10020358 ◽

2021 ◽

Vol 10 (2) ◽

pp. 358

Author(s):

Phui Yee Tan ◽

Beng Ti Tey ◽

Eng Seng Chan ◽

Oi Ming Lai ◽

Hon Weng Chang ◽

...

Keyword(s):

Calcium Carbonate ◽

Droplet Size ◽

Entrapment Efficiency ◽

Ph Sensitive ◽

Emulsion System ◽

Ph Responsive ◽

Small Droplet ◽

Homogenization Time ◽

Oil In Water ◽

Ph Range

Calcium carbonate (CaCO3) has been utilized as a pH-responsive component in various products. In this present work, palm tocotrienols-rich fraction (TRF) was successfully entrapped in a self-assembled oil-in-water (O/W) emulsion system by using CaCO3 as the stabilizer. The emulsion droplet size, viscosity and tocotrienols entrapment efficiency (EE) were strongly affected by varying the processing (homogenization speed and time) and formulation (CaCO3 and TRF concentrations) parameters. Our findings indicated that the combination of 5000 rpm homogenization speed, 15 min homogenization time, 0.75% CaCO3 concentration and 2% TRF concentration resulted in a high EE of tocotrienols (92.59–99.16%) and small droplet size (18.83 ± 1.36 µm). The resulting emulsion system readily released the entrapped tocotrienols across the pH range tested (pH 1–9); with relatively the highest release observed at pH 3. The current study presents a potential pH-sensitive emulsion system for the entrapment and delivery of palm tocotrienols.

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Emulsion Formation and Stabilizing Properties of Olive Oil Cake Crude Extracts

Processes ◽

10.3390/pr9040633 ◽

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.

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Influence of Whey Protein Micro-Gel Particles and Whey Protein Micro-Gel Particles-Xanthan Gum Complexes on the Stability of O/W Emulsions

Polymers ◽

10.3390/polym13142301 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2301

Author(s):

Man Zhang ◽

Bin Liang ◽

Hongjun He ◽

Changjian Ji ◽

Tingting Cui ◽

...

Keyword(s):

Oxidative Stability ◽

Whey Protein ◽

High Speed ◽

Xanthan Gum ◽

Physical Stability ◽

Theoretical Support ◽

Gel Particles ◽

Oil In Water ◽

The Stability ◽

The Impact

Appropriate pretreatment of proteins and addition of xanthan gum (XG) has the potential to improve the stability of oil-in-water (O/W) emulsions. However, the factors that regulate the enhancement and the mechanism are still not clear, which restricts the realization of improving the emulsion stability by directional design of its structure. Therefore, the effects of whey protein micro-gel particles (WPMPs) and WPMPs-XG complexes on the stability of O/W emulsion were investigated in this article to provide theoretical support. WPMPs with different structures were prepared by pretreatment (controlled high-speed shear treatment of heat-set WPC gels) at pH 3.5–8.5. The impact of initial WPC structure and XG addition on Turbiscan Indexes, mean droplet size and the peroxide values of O/W emulsions was investigated. The results indicate that WPMPs and XG can respectively inhibit droplet coalescence and gravitational separation to improve the physical stability of WPC-stabilized O/W emulsions. The pretreatment significantly enhanced the oxidative stability of WPC-stabilized O/W emulsions. The addition of XG did not necessarily enhance the oxidative stability of O/W emulsions. Whether the oxidative stability of the O/W emulsion with XG is increased or decreased depends on the interface structure of the protein-XG complex. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation.

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