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{{short description|Мешавина две или више течности које се углавном не мешају}}
[[Датотека:Emulsions.svg|frame|right|A. Две течности које се не мешају<br />B. Емулзија фазе II дисперговане у фази I<br />C. Нестабилна емулзија се прогресивно раздваја<br />D. [[Сурфактант]] (љубичасте кружнице око честица) се налазе на прелазу између фазе II и фазе I, чиме се стабилизује емулзија]]
[[Датотека:Emulsions.svg|thumb|250px|right|A. Две течности које се не мешају<br />B. Емулзија фазе II дисперговане у фази I<br />C. Нестабилна емулзија се прогресивно раздваја<br />D. [[Сурфактант]] (љубичасте кружнице око честица) се налазе на прелазу између фазе II и фазе I, чиме се стабилизује емулзија]]

'''Емулзија''' је смеша две немешљиве [[течност]]и, при чему је једна од ове две течности распоређена у облику капи у другој. Течност која је присутна у облику капи назива се дисперзна или диспергована фаза, док се течност у којој су капи распоређене назива континуална фаза.<ref name="Atkins7th">{{Atkins7th}}</ref> Примери емулзија у свакодневном животу су многи прехрамбени производи ([[мајонез]], [[маслац]], [[млеко]], [[маргарин]], [[чоколада]]), разне врсте козметичких препарата, неке вакцине и медицински препарати, боје и лакови, [[нафта]], итд. Процес добијања емулзија назива се [[емулговање]]. Средства за емулговање олакшавају добијање емулзија и повећавају њихову стабилност. Најчешће коришћена средства за емулговање су [[емулгатор]]и и стабилизатори.{{sfn|Dahl|1997|pp=}}
'''Емулзија''' је смеша две немешљиве [[течност]]и, при чему је једна од ове две течности распоређена у облику капи у другој. Течност која је присутна у облику капи назива се дисперзна или диспергована фаза, док се течност у којој су капи распоређене назива континуална фаза.<ref name="Atkins7th">{{Atkins7th}}</ref> Примери емулзија у свакодневном животу су многи прехрамбени производи ([[мајонез]], [[маслац]], [[млеко]], [[маргарин]], [[чоколада]]), разне врсте козметичких препарата, неке вакцине и медицински препарати, боје и лакови, [[нафта]], итд. Процес добијања емулзија назива се [[емулговање]]. Средства за емулговање олакшавају добијање емулзија и повећавају њихову стабилност. Најчешће коришћена средства за емулговање су [[емулгатор]]и и стабилизатори.{{sfn|Dahl|1997|pp=}}
{{rut}}
Two liquids can form different types of emulsions. As an example, oil and water can form, first, an oil-in-water emulsion, in which the oil is the dispersed phase, and water is the continuous phase. Second, they can form a water-in-oil emulsion, in which water is the dispersed phase and oil is the continuous phase. Multiple emulsions are also possible, including a "water-in-oil-in-water" emulsion and an "oil-in-water-in-oil" emulsion.<ref>{{cite journal|pmid=17076645 |year=2006 |last1=Khan |first1=A. Y. |title=Multiple emulsions: An overview |journal=Current Drug Delivery |volume=3 |issue=4 |pages=429–43 |last2=Talegaonkar |first2=S |last3=Iqbal |first3=Z |last4=Ahmed |first4=F. J. |last5=Khar |first5=R. K. |doi=10.2174/156720106778559056}}</ref>

== Етимологија ==
The word "emulsion" comes from the Latin ''emulgere'' "to milk out", from ''ex'' "out" + ''mulgere'' "to milk", as milk is an emulsion of fat and water, along with other components, including [[colloid]]al [[casein]] micelles (a type of secreted [[biomolecular condensate]]).<ref name="OnlineEtymol">{{cite web |last1=Harper |first1=Douglas |title=Online Etymology Dictionary |url=https://www.etymonline.com/search?q=emulsion |website=www..etymonline.com |publisher=Etymonline |access-date=2 November 2019}}</ref>

== Изглед и својства ==
{{Quote box
|title =[[International Union of Pure and Applied Chemistry|IUPAC]] definition
|quote = Fluid system in which liquid droplets are dispersed in a liquid.

''Note 1'': The definition is based on the definition in ref.<ref>{{cite book|title=Compendium of Chemical Terminology (The "Gold Book")|year=1997|publisher=[[Blackwell Scientific Publications]]|location=Oxford|author=IUPAC|chapter-url=http://goldbook.iupac.org/E02065.html|url-status=bot: unknown |archive-url= https://web.archive.org/web/20120310221658/http://goldbook.iupac.org/E02065.html|archive-date=2012-03-10 |doi=10.1351/goldbook.E02065 |chapter=Emulsion|isbn=978-0-9678550-9-7}}</ref>

''Note 2'': The droplets may be amorphous, liquid-crystalline, or any<br/>mixture thereof.

''Note 3'': The diameters of the droplets constituting the ''[[Dispersion (chemistry)|dispersed phase]]''<br/>usually range from approximately 10&nbsp;nm to 100&nbsp;μm; i.e., the droplets<br/>may exceed the usual size limits for [[colloid]]al particles.

''Note 4'': An emulsion is termed an oil/water (o/w) emulsion if the<br/>dispersed phase is an organic material and the ''continuous phase'' is<br/>water or an aqueous solution and is termed water/oil (w/o) if the dispersed<br/>phase is water or an aqueous solution and the continuous phase is an<br/>organic liquid (an "oil").

''Note 5'': A w/o emulsion is sometimes called an inverse emulsion.<br/>The term "inverse emulsion" is misleading, suggesting incorrectly that<br/>the emulsion has properties that are the opposite of those of an emulsion.<br/>Its use is, therefore, not recommended.<ref>{{cite journal|title=Terminology of polymers and polymerization processes in dispersed systems (IUPAC Recommendations 2011)|journal=[[Pure and Applied Chemistry]]|year=2011|volume=83|issue=12|pages=2229–2259|doi=10.1351/PAC-REC-10-06-03 |last1=Slomkowski |first1=Stanislaw |last2=Alemán|first2=José V.|last3=Gilbert|first3=Robert G. |last4=Hess |first4=Michael |last5=Horie |first5=Kazuyuki |last6=Jones |first6=Richard G. |last7=Kubisa |first7=Przemyslaw |last8=Meisel |first8=Ingrid |last9=Mormann |first9=Werner |last10=Penczek |first10=Stanisław |last11=Stepto|first11=Robert F. T.|s2cid=96812603|url=https://espace.library.uq.edu.au/view/UQ:266979/UQ266979_OA.pdf}}</ref>
}}

Emulsions contain both a dispersed and a continuous phase, with the boundary between the phases called the "interface".<ref name=":2">{{Citation|last1=Loi|first1=Chia Chun|title=Protein-Stabilised Emulsions|date=2018|work=Reference Module in Food Science |publisher=Elsevier |doi=10.1016/b978-0-08-100596-5.22490-6|isbn=9780081005965|last2=Eyres|first2=Graham T.|last3=Birch|first3=E. John}}</ref> Emulsions tend to have a cloudy appearance because the many [[phase boundary|phase interfaces]] [[scattering|scatter]] light as it passes through the emulsion. Emulsions appear [[white]] when all light is scattered equally. If the emulsion is dilute enough, higher-frequency (low-wavelength) light will be scattered more, and the emulsion will appear [[blue]]r&nbsp;– this is called the "[[Tyndall effect]]".<ref>{{Cite book|last=Joseph Price Remington|title=Remington's Pharmaceutical Sciences|editor-last=Alfonso R. Gennaro|publisher=Mack Publishing Company (Original from Northwestern University) (Digitized 2010)|year=1990|isbn=9780912734040|pages=281}}</ref> If the emulsion is concentrated enough, the color will be distorted toward comparatively longer wavelengths, and will appear more [[yellow]].

Two special classes of emulsions&nbsp;– [[microemulsion]]s and nanoemulsions, with droplet sizes below 100&nbsp;nm&nbsp;– appear translucent.<ref name="Mason">{{cite journal|vauthors=Mason TG, Wilking JN, Meleson K, Chang CB, Graves SM|title=Nanoemulsions: Formation, structure, and physical properties|journal=Journal of Physics: Condensed Matter|volume=18|issue=41|pages=R635–R666 |doi=10.1088/0953-8984/18/41/R01 |url=http://www.firp.ula.ve/archivos/pdf/06_JPCM_Mason.pdf |year=2006 |bibcode=2006JPCM...18R.635M |access-date=2016-10-26|archive-url= https://web.archive.org/web/20170112080749/http://www.firp.ula.ve/archivos/pdf/06_JPCM_Mason.pdf|archive-date=2017-01-12|url-status=dead}}</ref> This property is due to the fact that light waves are scattered by the droplets only if their sizes exceed about one-quarter of the wavelength of the incident light. Since the [[visible spectrum]] of light is composed of wavelengths between 390 and 750 [[nanometer]]s (nm), if the droplet sizes in the emulsion are below about 100&nbsp;nm, the light can penetrate through the emulsion without being scattered.<ref>{{cite journal|vauthors=Leong TS, Wooster TJ, Kentish SE, Ashokkumar M |title=Minimising oil droplet size using ultrasonic emulsification|journal=Ultrasonics Sonochemistry|volume=16|issue=6|pages=721–7 |pmid=19321375 |year=2009 |doi=10.1016/j.ultsonch.2009.02.008|hdl=11343/129835|url=http://minerva-access.unimelb.edu.au/bitstream/11343/129835/1/Minerva.pdf|doi-access=free}}</ref> Due to their similarity in appearance, translucent nanoemulsions and [[microemulsions]] are frequently confused. Unlike translucent nanoemulsions, which require specialized equipment to be produced, microemulsions are spontaneously formed by "solubilizing" oil molecules with a mixture of [[surfactant]]s, co-surfactants, and co-[[solvent]]s.<ref name="Mason" /> The required surfactant concentration in a [[microemulsion]] is, however, several times higher than that in a translucent nanoemulsion, and significantly exceeds the concentration of the dispersed phase. Because of many undesirable side-effects caused by surfactants, their presence is disadvantageous or prohibitive in many applications.

Common emulsions are inherently unstable and, thus, do not tend to form spontaneously. Energy input&nbsp;– through shaking, stirring, [[Homogenization (chemistry)|homogenizing]], or exposure to power [[ultrasound]]<ref>{{cite journal| doi=10.1016/j.ifset.2007.07.005 | volume=9 | issue=2 | title=The use of ultrasonics for nanoemulsion preparation | year=2008 | journal=Innovative Food Science & Emerging Technologies | pages=170–175 | last1 = Kentish | first1 = S. | last2 = Wooster | first2 = T.J. | last3 = Ashokkumar | first3 = M. | last4 = Balachandran | first4 = S. | last5 = Mawson | first5 = R. | last6 = Simons | first6 = L.| hdl=11343/55431 | hdl-access = free }}</ref>&nbsp;– is needed to form an emulsion. Over time, emulsions tend to revert to the stable state of the phases comprising the emulsion. An example of this is seen in the separation of the oil and vinegar components of [[vinaigrette (food)|vinaigrette]], an unstable emulsion that will quickly separate unless shaken almost continuously. There are important exceptions to this rule&nbsp;– [[microemulsions]] are [[thermodynamics|thermodynamically]] stable, while translucent nanoemulsions are [[Kinetics (physics)|kinetically]] stable.<ref name="Mason" />


=== Нестабилност ===
Emulsion stability refers to the ability of an emulsion to resist change in its properties over time.<ref name=":0">{{cite book|author=McClements, David Julian |title=Food Emulsions: Principles, Practices, and Techniques, Second Edition|url=https://books.google.com/books?id=wTrzBPbf_WQC&pg=PA269|date=16 December 2004|publisher=[[Taylor & Francis]]|isbn=978-0-8493-2023-1|pages=269–}}</ref><ref>{{cite journal|doi=10.1016/S0268-005X(99)00027-2|title=Influence of copper on the stability of whey protein stabilized emulsions|journal=Food Hydrocolloids |volume=13 |issue=5 |pages=419 |year=1999 |last1=Silvestre |first1=M.P.C. |last2=Decker |first2=E.A.|last3=McClements|first3=D.J.}}</ref> There are four types of instability in emulsions: [[flocculation]], [[creaming (chemistry)|creaming]]/[[sedimentation]], [[Coalescence (physics)|coalescence]], and [[Ostwald ripening]]. Flocculation occurs when there is an attractive force between the droplets, so they form flocs, like bunches of grapes. This process can be desired, if controlled in its extent, to tune physical properties of emulsions such as their flow behaviour. <ref>{{Cite journal|last1=Fuhrmann|first1=Philipp L.|last2=Sala|first2=Guido|last3=Stieger|first3=Markus|last4=Scholten|first4=Elke|date=2019-08-01|title=Clustering of oil droplets in o/w emulsions: Controlling cluster size and interaction strength|journal=Food Research International|volume=122|pages=537–547|doi=10.1016/j.foodres.2019.04.027|pmid=31229109|issn=0963-9969|doi-access=free}}</ref> Coalescence occurs when droplets bump into each other and combine to form a larger droplet, so the average droplet size increases over time. Emulsions can also undergo [[creaming (chemistry)|creaming]], where the droplets rise to the top of the emulsion under the influence of [[buoyancy]], or under the influence of the [[centripetal force]] induced when a [[centrifuge]] is used.<ref name=":0" /> Creaming is a common phenomenon in dairy and non-dairy beverages (i.e. milk, coffee milk, almond milk, soy milk) and usually does not change the droplet size.<ref name=":1">{{Cite journal|last1=Loi|first1=Chia Chun|last2=Eyres|first2=Graham T.|last3=Birch|first3=E. John|date=2019|title=Effect of mono- and diglycerides on physical properties and stability of a protein-stabilised oil-in-water emulsion|journal=Journal of Food Engineering|volume=240|pages=56–64|doi=10.1016/j.jfoodeng.2018.07.016|issn=0260-8774}}</ref> Sedimentation is the opposite phenomenon of creaming and normally observed in water-in-oil emulsions.<ref name=":2" /> Sedimentation happens when the dispersed phase is denser than the continuous phase and the gravitational forces pull the denser globules towards the bottom of the emulsion. Similar to creaming, sedimentation follows Stokes' law.

An appropriate "surface active agent" (or "[[surfactant]]") can increase the kinetic stability of an emulsion so that the size of the droplets does not change significantly with time. The stability of an emulsion, like a [[Suspension_(chemistry)|suspension]], can be studied in terms of [[zeta potential]], which indicates the repulsion between droplets or particles. If the size and dispersion of droplets does not change over time, it is said to be stable.<ref>{{Cite journal|last=Mcclements|first=David Julian|date=2007-09-27|title=Critical Review of Techniques and Methodologies for Characterization of Emulsion Stability|journal=Critical Reviews in Food Science and Nutrition|volume=47|issue=7|pages=611–649|doi=10.1080/10408390701289292|issn=1040-8398|pmid=17943495|s2cid=37152866}}</ref> For example, oil-in-water emulsions containing [[Mono- and diglycerides of fatty acids|mono- and diglycerides]] and milk protein as [[surfactant]] showed that stable oil droplet size over 28 days storage at 25°C.<ref name=":1" />

=== Праћење физичке стабилности ===
The stability of emulsions can be characterized using techniques such as light scattering, focused beam reflectance measurement, centrifugation, and [[rheology]]. Each method has advantages and disadvantages.<ref>{{Cite journal|last1=Dowding|first1=Peter J.|last2=Goodwin|first2=James W.|last3=Vincent|first3=Brian|date=2001-11-30|title=Factors governing emulsion droplet and solid particle size measurements performed using the focused beam reflectance technique|journal=Colloids and Surfaces A: Physicochemical and Engineering Aspects|volume=192|issue=1|pages=5–13|doi=10.1016/S0927-7757(01)00711-7|issn=0927-7757}}</ref>

=== Методе убрзања за предвиђање рока трајања ===
The kinetic process of destabilization can be rather long&nbsp;– up to several months, or even years for some products.<ref>{{Cite book|last=Dickinson|first=Eric|chapter=Emulsion Stability|date=1993|work=Food Hydrocolloids: Structures, Properties, and Functions|pages=387–398|editor-last=Nishinari|editor-first=Katsuyoshi|publisher=Springer US|language=en|doi=10.1007/978-1-4615-2486-1_61 |isbn=9781461524861|editor2-last=Doi|editor2-first=Etsushiro|title=Food Hydrocolloids}}</ref> Often the formulator must accelerate this process in order to test products in a reasonable time during product design. Thermal methods are the most commonly used – these consist of increasing the emulsion temperature to accelerate destabilization (if below critical temperatures for phase inversion or chemical degradation).<ref>{{Cite journal|last1=Masmoudi|first1=H.|last2=Dréau|first2=Y. Le |last3=Piccerelle |first3=P. |last4=Kister |first4=J.|date=2005-01-31|title=The evaluation of cosmetic and pharmaceutical emulsions aging process using classical techniques and a new method: FTIR|journal=International Journal of Pharmaceutics|volume=289|issue=1|pages=117–131 |doi=10.1016/j.ijpharm.2004.10.020|pmid=15652205|issn=0378-5173}}</ref> Temperature affects not only the viscosity but also the interfacial tension in the case of non-ionic surfactants or, on a broader scope, interactions between droplets within the system.


== Референце ==
== Референце ==
{{reflist|30em}}
{{reflist|}}


== Литература ==
== Литература ==
{{refbegin|}}
* {{Cite book |ref= harv|last=Dahl|first=Per F.|title=Flash of the Cathode Rays: A History of J J Thomson's Electron|url=https://books.google.com/books?id=xUzaWGocMdMC|year=1997|publisher=CRC Press|isbn=978-0-7503-0453-5}}
* {{Cite book |ref= harv|last=Dahl|first=Per F.|title=Flash of the Cathode Rays: A History of J J Thomson's Electron|url=https://books.google.com/books?id=xUzaWGocMdMC|year=1997|publisher=CRC Press|isbn=978-0-7503-0453-5}}
* {{cite book|author1=Philip Sherman|author2-link=British Society of Rheology|author2=British Society of Rheology|title=Rheology of emulsions: proceedings of a symposium held by the British Society of Rheology ... Harrogate, October 1962|url=https://books.google.com/books?id=UJ0FAQAAIAAJ|year=1963|publisher=Macmillan|isbn=9780080102900}}
* ''Handbook of Nanostructured Materials and Nanotechnology; Nalwa, H.S., Ed.; Academic Press: New York, NY, USA, 2000; Volume 5, pp. 501–575''
{{refend}}


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Верзија на датум 27. октобар 2021. у 23:21

A. Две течности које се не мешају
B. Емулзија фазе II дисперговане у фази I
C. Нестабилна емулзија се прогресивно раздваја
D. Сурфактант (љубичасте кружнице око честица) се налазе на прелазу између фазе II и фазе I, чиме се стабилизује емулзија

Емулзија је смеша две немешљиве течности, при чему је једна од ове две течности распоређена у облику капи у другој. Течност која је присутна у облику капи назива се дисперзна или диспергована фаза, док се течност у којој су капи распоређене назива континуална фаза.[1] Примери емулзија у свакодневном животу су многи прехрамбени производи (мајонез, маслац, млеко, маргарин, чоколада), разне врсте козметичких препарата, неке вакцине и медицински препарати, боје и лакови, нафта, итд. Процес добијања емулзија назива се емулговање. Средства за емулговање олакшавају добијање емулзија и повећавају њихову стабилност. Најчешће коришћена средства за емулговање су емулгатори и стабилизатори.[2]

Two liquids can form different types of emulsions. As an example, oil and water can form, first, an oil-in-water emulsion, in which the oil is the dispersed phase, and water is the continuous phase. Second, they can form a water-in-oil emulsion, in which water is the dispersed phase and oil is the continuous phase. Multiple emulsions are also possible, including a "water-in-oil-in-water" emulsion and an "oil-in-water-in-oil" emulsion.[3]

Етимологија

The word "emulsion" comes from the Latin emulgere "to milk out", from ex "out" + mulgere "to milk", as milk is an emulsion of fat and water, along with other components, including colloidal casein micelles (a type of secreted biomolecular condensate).[4]

Изглед и својства

IUPAC definition

Fluid system in which liquid droplets are dispersed in a liquid.

Note 1: The definition is based on the definition in ref.[5]

Note 2: The droplets may be amorphous, liquid-crystalline, or any
mixture thereof.

Note 3: The diameters of the droplets constituting the dispersed phase
usually range from approximately 10 nm to 100 μm; i.e., the droplets
may exceed the usual size limits for colloidal particles.

Note 4: An emulsion is termed an oil/water (o/w) emulsion if the
dispersed phase is an organic material and the continuous phase is
water or an aqueous solution and is termed water/oil (w/o) if the dispersed
phase is water or an aqueous solution and the continuous phase is an
organic liquid (an "oil").

Note 5: A w/o emulsion is sometimes called an inverse emulsion.
The term "inverse emulsion" is misleading, suggesting incorrectly that
the emulsion has properties that are the opposite of those of an emulsion.
Its use is, therefore, not recommended.[6]

Emulsions contain both a dispersed and a continuous phase, with the boundary between the phases called the "interface".[7] Emulsions tend to have a cloudy appearance because the many phase interfaces scatter light as it passes through the emulsion. Emulsions appear white when all light is scattered equally. If the emulsion is dilute enough, higher-frequency (low-wavelength) light will be scattered more, and the emulsion will appear bluer – this is called the "Tyndall effect".[8] If the emulsion is concentrated enough, the color will be distorted toward comparatively longer wavelengths, and will appear more yellow.

Two special classes of emulsions – microemulsions and nanoemulsions, with droplet sizes below 100 nm – appear translucent.[9] This property is due to the fact that light waves are scattered by the droplets only if their sizes exceed about one-quarter of the wavelength of the incident light. Since the visible spectrum of light is composed of wavelengths between 390 and 750 nanometers (nm), if the droplet sizes in the emulsion are below about 100 nm, the light can penetrate through the emulsion without being scattered.[10] Due to their similarity in appearance, translucent nanoemulsions and microemulsions are frequently confused. Unlike translucent nanoemulsions, which require specialized equipment to be produced, microemulsions are spontaneously formed by "solubilizing" oil molecules with a mixture of surfactants, co-surfactants, and co-solvents.[9] The required surfactant concentration in a microemulsion is, however, several times higher than that in a translucent nanoemulsion, and significantly exceeds the concentration of the dispersed phase. Because of many undesirable side-effects caused by surfactants, their presence is disadvantageous or prohibitive in many applications.

Common emulsions are inherently unstable and, thus, do not tend to form spontaneously. Energy input – through shaking, stirring, homogenizing, or exposure to power ultrasound[11] – is needed to form an emulsion. Over time, emulsions tend to revert to the stable state of the phases comprising the emulsion. An example of this is seen in the separation of the oil and vinegar components of vinaigrette, an unstable emulsion that will quickly separate unless shaken almost continuously. There are important exceptions to this rule – microemulsions are thermodynamically stable, while translucent nanoemulsions are kinetically stable.[9]


Нестабилност

Emulsion stability refers to the ability of an emulsion to resist change in its properties over time.[12][13] There are four types of instability in emulsions: flocculation, creaming/sedimentation, coalescence, and Ostwald ripening. Flocculation occurs when there is an attractive force between the droplets, so they form flocs, like bunches of grapes. This process can be desired, if controlled in its extent, to tune physical properties of emulsions such as their flow behaviour. [14] Coalescence occurs when droplets bump into each other and combine to form a larger droplet, so the average droplet size increases over time. Emulsions can also undergo creaming, where the droplets rise to the top of the emulsion under the influence of buoyancy, or under the influence of the centripetal force induced when a centrifuge is used.[12] Creaming is a common phenomenon in dairy and non-dairy beverages (i.e. milk, coffee milk, almond milk, soy milk) and usually does not change the droplet size.[15] Sedimentation is the opposite phenomenon of creaming and normally observed in water-in-oil emulsions.[7] Sedimentation happens when the dispersed phase is denser than the continuous phase and the gravitational forces pull the denser globules towards the bottom of the emulsion. Similar to creaming, sedimentation follows Stokes' law.

An appropriate "surface active agent" (or "surfactant") can increase the kinetic stability of an emulsion so that the size of the droplets does not change significantly with time. The stability of an emulsion, like a suspension, can be studied in terms of zeta potential, which indicates the repulsion between droplets or particles. If the size and dispersion of droplets does not change over time, it is said to be stable.[16] For example, oil-in-water emulsions containing mono- and diglycerides and milk protein as surfactant showed that stable oil droplet size over 28 days storage at 25°C.[15]

Праћење физичке стабилности

The stability of emulsions can be characterized using techniques such as light scattering, focused beam reflectance measurement, centrifugation, and rheology. Each method has advantages and disadvantages.[17]

Методе убрзања за предвиђање рока трајања

The kinetic process of destabilization can be rather long – up to several months, or even years for some products.[18] Often the formulator must accelerate this process in order to test products in a reasonable time during product design. Thermal methods are the most commonly used – these consist of increasing the emulsion temperature to accelerate destabilization (if below critical temperatures for phase inversion or chemical degradation).[19] Temperature affects not only the viscosity but also the interfacial tension in the case of non-ionic surfactants or, on a broader scope, interactions between droplets within the system.

Референце

  1. ^ Peter Atkins; Julio de Paula (2001). Physical Chemistry (7th изд.). W. H. Freeman. ISBN 0716735393. 
  2. ^ Dahl 1997.
  3. ^ Khan, A. Y.; Talegaonkar, S; Iqbal, Z; Ahmed, F. J.; Khar, R. K. (2006). „Multiple emulsions: An overview”. Current Drug Delivery. 3 (4): 429—43. PMID 17076645. doi:10.2174/156720106778559056. 
  4. ^ Harper, Douglas. „Online Etymology Dictionary”. www..etymonline.com. Etymonline. Приступљено 2. 11. 2019. 
  5. ^ IUPAC (1997). „Emulsion”. Compendium of Chemical Terminology (The "Gold Book"). Oxford: Blackwell Scientific Publications. ISBN 978-0-9678550-9-7. doi:10.1351/goldbook.E02065. Архивирано из оригинала 2012-03-10. г. 
  6. ^ Slomkowski, Stanislaw; Alemán, José V.; Gilbert, Robert G.; Hess, Michael; Horie, Kazuyuki; Jones, Richard G.; Kubisa, Przemyslaw; Meisel, Ingrid; Mormann, Werner; Penczek, Stanisław; Stepto, Robert F. T. (2011). „Terminology of polymers and polymerization processes in dispersed systems (IUPAC Recommendations 2011)” (PDF). Pure and Applied Chemistry. 83 (12): 2229—2259. S2CID 96812603. doi:10.1351/PAC-REC-10-06-03. 
  7. ^ а б Loi, Chia Chun; Eyres, Graham T.; Birch, E. John (2018), „Protein-Stabilised Emulsions”, Reference Module in Food Science, Elsevier, ISBN 9780081005965, doi:10.1016/b978-0-08-100596-5.22490-6 
  8. ^ Joseph Price Remington (1990). Alfonso R. Gennaro, ур. Remington's Pharmaceutical Sciences. Mack Publishing Company (Original from Northwestern University) (Digitized 2010). стр. 281. ISBN 9780912734040. 
  9. ^ а б в Mason TG, Wilking JN, Meleson K, Chang CB, Graves SM (2006). „Nanoemulsions: Formation, structure, and physical properties” (PDF). Journal of Physics: Condensed Matter. 18 (41): R635—R666. Bibcode:2006JPCM...18R.635M. doi:10.1088/0953-8984/18/41/R01. Архивирано из оригинала (PDF) 2017-01-12. г. Приступљено 2016-10-26. 
  10. ^ Leong TS, Wooster TJ, Kentish SE, Ashokkumar M (2009). „Minimising oil droplet size using ultrasonic emulsification” (PDF). Ultrasonics Sonochemistry. 16 (6): 721—7. PMID 19321375. doi:10.1016/j.ultsonch.2009.02.008 Слободан приступ. hdl:11343/129835. 
  11. ^ Kentish, S.; Wooster, T.J.; Ashokkumar, M.; Balachandran, S.; Mawson, R.; Simons, L. (2008). „The use of ultrasonics for nanoemulsion preparation”. Innovative Food Science & Emerging Technologies. 9 (2): 170—175. doi:10.1016/j.ifset.2007.07.005. hdl:11343/55431 Слободан приступ. 
  12. ^ а б McClements, David Julian (16. 12. 2004). Food Emulsions: Principles, Practices, and Techniques, Second Edition. Taylor & Francis. стр. 269—. ISBN 978-0-8493-2023-1. 
  13. ^ Silvestre, M.P.C.; Decker, E.A.; McClements, D.J. (1999). „Influence of copper on the stability of whey protein stabilized emulsions”. Food Hydrocolloids. 13 (5): 419. doi:10.1016/S0268-005X(99)00027-2. 
  14. ^ Fuhrmann, Philipp L.; Sala, Guido; Stieger, Markus; Scholten, Elke (2019-08-01). „Clustering of oil droplets in o/w emulsions: Controlling cluster size and interaction strength”. Food Research International. 122: 537—547. ISSN 0963-9969. PMID 31229109. doi:10.1016/j.foodres.2019.04.027 Слободан приступ. 
  15. ^ а б Loi, Chia Chun; Eyres, Graham T.; Birch, E. John (2019). „Effect of mono- and diglycerides on physical properties and stability of a protein-stabilised oil-in-water emulsion”. Journal of Food Engineering. 240: 56—64. ISSN 0260-8774. doi:10.1016/j.jfoodeng.2018.07.016. 
  16. ^ Mcclements, David Julian (2007-09-27). „Critical Review of Techniques and Methodologies for Characterization of Emulsion Stability”. Critical Reviews in Food Science and Nutrition. 47 (7): 611—649. ISSN 1040-8398. PMID 17943495. S2CID 37152866. doi:10.1080/10408390701289292. 
  17. ^ Dowding, Peter J.; Goodwin, James W.; Vincent, Brian (2001-11-30). „Factors governing emulsion droplet and solid particle size measurements performed using the focused beam reflectance technique”. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 192 (1): 5—13. ISSN 0927-7757. doi:10.1016/S0927-7757(01)00711-7. 
  18. ^ Dickinson, Eric (1993). „Emulsion Stability”. Ур.: Nishinari, Katsuyoshi; Doi, Etsushiro. Food Hydrocolloids. Food Hydrocolloids: Structures, Properties, and Functions (на језику: енглески). Springer US. стр. 387—398. ISBN 9781461524861. doi:10.1007/978-1-4615-2486-1_61. 
  19. ^ Masmoudi, H.; Dréau, Y. Le; Piccerelle, P.; Kister, J. (2005-01-31). „The evaluation of cosmetic and pharmaceutical emulsions aging process using classical techniques and a new method: FTIR”. International Journal of Pharmaceutics. 289 (1): 117—131. ISSN 0378-5173. PMID 15652205. doi:10.1016/j.ijpharm.2004.10.020. 

Литература

Преузето из „https://sr.wikipedia.org/w/index.php?title=Емулзија&oldid=24113154”