{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T05:39:32Z","timestamp":1771047572993,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,18]],"date-time":"2020-12-18T00:00:00Z","timestamp":1608249600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia, FCT","award":["UID\/QUI\/50006\/2019"],"award-info":[{"award-number":["UID\/QUI\/50006\/2019"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia, FCT","award":["PTDC\/OCE-ETA\/32492\/2017 \u2013 POCI-01-0145-FEDER-032492"],"award-info":[{"award-number":["PTDC\/OCE-ETA\/32492\/2017 \u2013 POCI-01-0145-FEDER-032492"]}]},{"name":"Funda\u00e7\u00e3o para a Tecnologia, FCT","award":["SFRH\/BD\/100889\/2014"],"award-info":[{"award-number":["SFRH\/BD\/100889\/2014"]}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["10TAL314003PR"],"award-info":[{"award-number":["10TAL314003PR"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>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, (\u03a6I) and oil (\u03a6O) 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\u2013200 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, \u03a6I, 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.<\/jats:p>","DOI":"10.3390\/foods9121897","type":"journal-article","created":{"date-parts":[[2020,12,21]],"date-time":"2020-12-21T04:12:01Z","timestamp":1608523921000},"page":"1897","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Interfacial Concentrations of Hydroxytyrosol Derivatives in Fish Oil-in-Water Emulsions and Nanoemulsions and Its Influence on Their Lipid Oxidation: Droplet Size Effects"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9614-409X","authenticated-orcid":false,"given":"Marlene","family":"Costa","sequence":"first","affiliation":[{"name":"REQUIMTE-LAQV, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9447-5626","authenticated-orcid":false,"given":"Sonia","family":"Losada-Barreiro","sequence":"additional","affiliation":[{"name":"REQUIMTE-LAQV, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"},{"name":"Departamento de Qu\u00edmica-F\u00edsica, Facultade de Qu\u00edmica, Universidade de Vigo, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9468-0881","authenticated-orcid":false,"given":"Carlos","family":"Bravo-D\u00edaz","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica-F\u00edsica, Facultade de Qu\u00edmica, Universidade de Vigo, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7779-9250","authenticated-orcid":false,"given":"Lu\u00eds S.","family":"Monteiro","sequence":"additional","affiliation":[{"name":"Chemistry Centre, University of Minho, Gualtar, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1149-6876","authenticated-orcid":false,"given":"F\u00e1tima","family":"Paiva-Martins","sequence":"additional","affiliation":[{"name":"REQUIMTE-LAQV, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Jacobsen, C., Nielsen, N.S., Horn, A.F., and S\u00f8rensen, A.D.M. (2013). Food Enrichment with Omega-3 Fatty Acids, Elsevier.","DOI":"10.1533\/9780857098863"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"842","DOI":"10.1111\/j.1440-1681.2006.04451.x","article-title":"Omega-3 fatty acids and hypertension in humans","volume":"33","author":"Mori","year":"2006","journal-title":"Clin. Exp. Pharmacol. Physiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1080\/1828051X.2015.1128687","article-title":"From farm to fork: Lipid oxidation in fish products. A review","volume":"15","author":"Secci","year":"2016","journal-title":"Ital. J. Anim. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4067","DOI":"10.1039\/b922183m","article-title":"Lipid oxidation and improving the oxidative stability","volume":"39","author":"Shahidi","year":"2010","journal-title":"Chem. Soc. Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1415","DOI":"10.1007\/s00217-017-2852-z","article-title":"Influence of droplet size on the antioxidant efficacy of oil-in-water emulsions loaded with rosemary in raw fermented sausages","volume":"243","author":"Erdmann","year":"2017","journal-title":"Eur. Food Res. Technol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1094","DOI":"10.1002\/mnfr.200600303","article-title":"Dietary advanced lipid oxidation endproducts are risk factors to human health","volume":"51","author":"Kanner","year":"2007","journal-title":"Mol. Nutr. Food Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2093","DOI":"10.1021\/tx200314p","article-title":"Dietary n-3 Polyunsaturated Fatty Acids and the Paradox of Their Health Benefits and Potential Harmful Effects","volume":"24","author":"Serini","year":"2011","journal-title":"Chem. Res. Toxicol."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Pokorn\u00fd, J., Yanishlieva, N., and Gordon, M. (2001). Antioxidants in Food: Practical Applications, Elsevier.","DOI":"10.1201\/9781439823057"},{"key":"ref_9","unstructured":"Barclay, L.R.C., and Vinqvist, M.R. (2003). The Chemistry of Phenols, John Wiley & Sons."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Shahidi, F. (2015). Handbook of Antioxidants for Food Preservation, Woodhead Publishing.","DOI":"10.1016\/B978-1-78242-089-7.00001-4"},{"key":"ref_11","unstructured":"Wanasundara, P.K.J.P., Shahidi, F., and Shahidi, F. (2005). Bailey\u2019s Industrial Oil and Fat Products, Wiley."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"192","DOI":"10.1016\/j.foodres.2018.06.007","article-title":"Modulating the interfacial concentration of gallates to improve the oxidative stability of fish oil-in-water emulsions","volume":"112","author":"Ferreira","year":"2018","journal-title":"Food Res. Int."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4429","DOI":"10.1039\/C8FO00977E","article-title":"Enhancement of the antioxidant efficiency of gallic acid derivatives in intact fish oil-in-water emulsions through optimization of their interfacial concentrations","volume":"9","year":"2018","journal-title":"Food Funct."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1016\/j.foodchem.2014.10.016","article-title":"A direct correlation between the antioxidant efficiencies of caffeic acid and its alkyl esters and their concentrations in the interfacial region of olive oil emulsions. the pseudophase model interpretation of the \u201ccut-off\u201d effect","volume":"175","author":"Costa","year":"2015","journal-title":"Food Chem."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"125716","DOI":"10.1016\/j.foodchem.2019.125716","article-title":"Influence of AO chain length, droplet size and oil to water ratio on the distribution and on the activity of gallates in fish oil-in-water emulsified systems: Emulsion and nanoemulsion comparison","volume":"310","author":"Costa","year":"2020","journal-title":"Food Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1600277","DOI":"10.1002\/ejlt.201600277","article-title":"Using a pseudophase model to determine AO distributions in emulsions: Why dynamic equilibrium matters","volume":"119","author":"Romsted","year":"2017","journal-title":"Eur. J. Lipid Sci. Technol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"8961","DOI":"10.1021\/acs.langmuir.5b00112","article-title":"To Model Chemical Reactivity in Heterogeneous Emulsions, Think Homogeneous Microemulsions","volume":"31","author":"Romsted","year":"2015","journal-title":"Langmuir"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"945","DOI":"10.1111\/1541-4337.12097","article-title":"Lipid Oxidation in Oil-in-Water Emulsions: Involvement of the Interfacial Layer","volume":"13","author":"Ropers","year":"2014","journal-title":"Compr. Rev. Food Sci. Food Saf."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1039\/C2FO10198J","article-title":"Influence of droplet size on the efficacy of oil-in-water emulsions loaded with phenolic antimicrobials","volume":"3","author":"Terjung","year":"2012","journal-title":"Food Funct."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"e12316","DOI":"10.1111\/jfpe.12316","article-title":"Assessment of Oxidative Stability in Fish Oil-in-Water Emulsions: Effect of Emulsification Process, Droplet Size and Storage Temperature","volume":"40","author":"Neves","year":"2017","journal-title":"J. Food Process Eng."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1016\/j.tifs.2017.07.001","article-title":"Hurdles in predicting antioxidant efficacy in oil-in-water emulsions","volume":"67","author":"Decker","year":"2017","journal-title":"Trends food Sci. Technol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1007\/s11745-005-1410-4","article-title":"Effects of droplet size on the oxidative stability of oil-in-water emulsions","volume":"40","author":"Nakaya","year":"2005","journal-title":"Lipids"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"329","DOI":"10.5650\/jos.58.329","article-title":"Effect of Droplet Size on the Oxidative Stability of Soybean Oil TAG and Fish Oil TAG in Oil-in-Water Emulsion","volume":"58","author":"Azuma","year":"2009","journal-title":"J. Oleo Sci."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.jcis.2012.08.069","article-title":"Fabrication of vitamin E-enriched nanoemulsions: Factors affecting particle size using spontaneous emulsification","volume":"391","author":"Saberi","year":"2013","journal-title":"J. Colloid Interface Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1016\/j.jcis.2019.12.011","article-title":"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","volume":"562","author":"Costa","year":"2020","journal-title":"J. Colloid Interface Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3917","DOI":"10.1002\/jsfa.9615","article-title":"Control of antioxidant efficiency of chlorogenates in emulsions: Modulation of antioxidant interfacial concentrations","volume":"99","author":"Meireles","year":"2019","journal-title":"J. Sci. Food Agric."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"5274","DOI":"10.1021\/acs.jafc.6b01468","article-title":"Interfacial Concentrations of Hydroxytyrosol and Its Lipophilic Esters in Intact Olive Oil-in-Water Emulsions: Effects of Antioxidant Hydrophobicity, Surfactant Concentration, and the Oil-to-Water Ratio on the Oxidative Stability of the Emulsions","volume":"64","author":"Almeida","year":"2016","journal-title":"J. Agric. Food Chem."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1002\/jsfa.2740620106","article-title":"Influence of fatty acids of different unsaturation in the oxidation of purified vegetable oils during microwave irradiation","volume":"62","author":"Yoshida","year":"1993","journal-title":"J. Sci. Food Agric."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1021\/jf60217a041","article-title":"Emulsifying properties of proteins: Evaluation of a turbidimetric technique","volume":"26","author":"Pearce","year":"1978","journal-title":"J. Agric. Food Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"655","DOI":"10.1021\/jf00004a005","article-title":"Determination of interfacial areas in emulsions using turbidimetric and droplet size data: Correction of the formula for emulsifying activity index","volume":"39","author":"Cameron","year":"1991","journal-title":"J. Agric. Food Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"6533","DOI":"10.1021\/jf400981x","article-title":"A Maximum in Antioxidant Distributions and Efficiencies with Increasing Hydrophobicity of Gallic Acid and its Alkyl Esters. The Pseudophase Model Interpretation of the \u201cCut-Off\u201d Effect","volume":"61","author":"Romsted","year":"2013","journal-title":"J. Agric. Food. Chem."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1021\/ar0682029","article-title":"Solvent Effects on the Rates and Mechanisms of Reaction of Phenols with Free Radicals","volume":"40","author":"Litwinienko","year":"2007","journal-title":"Acc. Chem. Res."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jcis.2012.07.036","article-title":"Effects of Emulsifier Hydrophile-Lipophile Balance and Emulsifier Concentration on the Distributions of Gallic acid, Propyl Gallate, and alpha-Tocopherol in Corn Oil Emulsions","volume":"389","year":"2013","journal-title":"J. Colloid Interface Sci."}],"container-title":["Foods"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2304-8158\/9\/12\/1897\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:47:12Z","timestamp":1760179632000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2304-8158\/9\/12\/1897"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,12,18]]},"references-count":33,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["foods9121897"],"URL":"https:\/\/doi.org\/10.3390\/foods9121897","relation":{},"ISSN":["2304-8158"],"issn-type":[{"value":"2304-8158","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,12,18]]}}}