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Extracellular vesicles (EVs) are nanoscopic structures that are involved in intercellular communication. Recent works have highlighted the existence of these assemblies in several plants and shown that they are able to vectorize hydrophilic and lipophilic molecules. In this study, we have isolated EVs from the two main olive oil by‐products (wastewaters [WWs] and pomace) by differential centrifugation/ultracentrifugation and have characterized their main physicochemical properties (size, charge, multimolecular structure, lipid and phenolic contents) and radical scavenging activity. Lipid content in EV fractions was 3.4 (0.2) % (% dry material) for WWEVs and 7.7 (0.3) % and 5.9 (0.9) % for EVs, respectively, from plurivarietal or monovarietal pomaces. Polar lipids represented around 49% of total lipids, and their profiles were globally similar in all EVs. Phosphatidylcholine and phosphatidic acid were the more abundant molecules. Their phenolic contents ranged from 2.1 to 4.6 mg hydroxytyrosol (HT) eq g−1 of raw material, with HT, oleuropein, and verbascoside being among the most abundant. Transmission electron cryomicroscopy showed the presence of spherical vesicles delimited by a single bilayer of amphiphilic lipids. Finally, the 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity of EVs was high and depended on their original by‐product type. Practical Application: Recent works have highlighted the existence of extracellular vesicles in several plants and shown that they are able to vectorize hydrophilic and lipophilic molecules. Herein, we have isolated and provided a chemical characterization of such vesicles from olive wastewater and pomace. Results showed that these vesicles are rich in the phenolic compounds that are generally found in olives and that the potential radical scavenging activity of extracellular vesicles from olive could be valorized as new antioxidants for the food or cosmetic sectors. [ABSTRACT FROM AUTHOR]

Four Deep Eutectic Solvents (DES) based on choline chloride (ChCl) and different hydrogen bond donors (1,4‐butanediol, glycerol, isosorbide, and urea) were tested as reaction medium for the immobilized Candida antarctica B (iCALB) lipase‐catalyzed esterification of fatty acids with n‐butanol. Although the strong hydrogen bonds between DES components were expected to lower their reactivity, all except urea, competed in the esterification reaction. To study the effect of acyl group donor and water, different chain length of saturated fatty acids (ranging from 6:0 to 18:0) and water content (ranging from 0, 1, 2 or 3 molar ratio of water/ChCl) were tested in the lipase‐catalyzed esterification with n‐butanol in ChCl:urea (1:2, molar ratio). When the incubation was performed in the absence of water, the shorter the fatty acid chain length, the higher the conversion. Upon water addition, a drastic increase in the esterification rate of all the fatty acids was observed and, conversely to what occurred in the anhydrous media, the longer the fatty acid chain length, the higher the conversion. Results suggest that water concentration in the DES medium possesses a multifactorial effect, as it influences the enzyme activity, the solvent viscosity, the DES structure, and the interaction between DES components, substrates, and enzymes, thus determining the efficiency and yield of the esterification reaction. [ABSTRACT FROM AUTHOR]

Infant follow‐on formulas (IFF) mimic human milk. This study aimed to identify the key structural levers that influence oxidative stability of IFF. Representative model IFF of marketed products in term of lipid composition were formulated with varying droplet size, lipid droplet core composition, and interfacial composition using different emulsifiers (soy lecithin or dairy phospholipids [DPL]). The oxidative stability of model IFF was assessed in accelerated storage conditions. No significant stabilization effect based on the lipid droplet core composition was observed. However, the nature of the interface, influenced by the emulsifier type, had an impact. Model IFF with DPL showed no loss of tocopherols and peroxide value was up to twice lower than those with soy lecithin after 20 days. This effect was particularly pronounced for the 0.4µm droplets. These results suggest that model IFF with DPL had a greater oxidative stability, likely due to the presence of sphingomyelin and the formation of a rigidified domain at the droplet surface. Model IFF with 0.4 µm droplets stabilized with soy lecithin, especially when added to the water phase, showed a tocopherols loss twice as high as that of IFF with DPL. These results indicate that oxidative stability of IFF is more influenced by the chemical environment rather than droplet size. Practical Application: Infant follow‐on formulas (IFF) aim to ensure an adequate nutritional intake to support the proper development and infant growth. Therefore, IFF must be stable against degradation phenomena such as lipid oxidation and have a composition and structure that are as biomimetic as possible to mature breast milk. This study provides key information for the development of IFF with a lipid composition and structure that are suitable for the infant nutritional needs and have an acceptable resistance to lipid oxidation. More generally, these results can be applied to all dispersed systems in the form of oil‐in‐water emulsions with a similar composition. [ABSTRACT FROM AUTHOR]

Lipid oxidation is a major concern in the food, cosmetic, and pharmaceutical sectors. The degradation of unsaturated lipids affects the nutritional, physicochemical, and organoleptic properties of products and can lead to off‐flavors and to the formation of potentially harmful oxidation compounds. To prevent or slow down lipid oxidation, different antioxidant additives are used alone or in combination to achieve the best possible efficiency with the minimum possible quantities. In manufactured products, that is, heterogeneous systems containing lipids as emulsions or bulk phase, the efficiency of an antioxidant is determined not only by its chemical reactivity, but also by its physical properties and its interaction with other compounds present in the products. The antioxidants most widely used on the industrial scale are probably tocopherols, either as natural extracts or pure synthetic molecules. Considerable research has been conducted on their antioxidant activity, but results regarding their efficiency are contradictory. Here, we review the known mechanisms behind the antioxidant activity of tocopherols and discuss the chemical and physical features that determine their efficacy. We first describe their chemical reactivity linked with the main factors that modulate it between efficient antioxidant capacity and potential prooxidant effects. We then describe their chemical interactions with other molecules (phenolic compounds, metals, vitamin C, carotenes, proteins, and phospholipids) that have potential additive, synergistic, or antagonist effects. Finally, we discuss other physical parameters that influence their activity in complex systems including their specific interactions with surfactants in emulsions and their behavior in the presence of association colloids in bulk oils. [ABSTRACT FROM AUTHOR]