Effect of lipophilization on the distribution and reactivity of ingredients in emulsions

Leong Wai Fun, Berton-Carabin Claire C., Elias Ryan J., Lecomte Jérôme, Villeneuve Pierre, Zhao Yu, Coupland John N.. 2015. Effect of lipophilization on the distribution and reactivity of ingredients in emulsions. Journal of Colloid and Interface Science, 459 : 36-43.

https://doi.org/10.1016/j.jcis.2015.07.070

Article de revue ; Article de recherche ; Article de revue à facteur d'impact

Version publiée - Anglais
Accès réservé aux personnels Cirad
Utilisation soumise à autorisation de l'auteur ou du Cirad.
Leong et al 2015.pdf
Télécharger (938kB) | Demander une copie

Quartile : Q2, Sujet : CHEMISTRY, PHYSICAL

Résumé : Hypothesis: The reactivity of small molecules in emulsions is believed to depend on their partitioning between phases, yet this is hard to verify experimentally in situ. In the present work, we use electron paramagnetic resonance (EPR) spectroscopy to simultaneously measure the distribution and reactivity of a homologous series of lipophilized spin probes in an emulsion. Experiments: 4-Hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPOL) was derivatized with saturated fatty acids to create a series of spin probes with increasing lipophilicity (C4-, C8-, C12-, and C16-TEMPO). The probes were added to a 10 wt.% tetradecane-in water emulsions (d32 _ 190 nm) stabilized with sodium caseinate (1 wt.% in the aqueous phase, pH 7). The distribution of the probes between phases was measured by electron paramagnetic resonance (EPR) spectroscopy. Findings: TEMPOL partitioned into the aqueous phase, C4-TEMPO distributed between the lipid and aqueous phases (69% and 31% respectively) while the more lipophilic probes dissolved exclusively within the lipid droplets. Interestingly, the more lipophilic probes initially precipitated upon their addition to the emulsion, and only slowly redistributed to the droplets over hours or days, the rate of which was dependent on their carbon chain length. The reactivity of the probes with aqueous an aqueous phase reductant (ascorbate) generally depended on the proportion in the aqueous phase (i.e., TEMPOL > C4-TEMPO > C8-TEMPO _ C12-TEMPO _ C16-TEMPO).

Mots-clés Agrovoc : spectroscopie, acide gras, spectroscopie RPE, filage, caséinate, caséinate de sodium, émulsion, mesure (activité)

Mots-clés géographiques Agrovoc : France

Classification Agris : Q02 - Traitement et conservation des produits alimentaires

Champ stratégique Cirad : Axe 3 (2014-2018) - Alimentation durable

Auteurs et affiliations