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Directed isomerisation of safflower oil under very low hydrogen partial pressure of 7 psi over a novel bifunctional highly structured rhodium-based catalyst (Rh/SBA-15), having narrow pore size distribution ranging from 4 to 8 nm, and BET-specific surface of ≈1,000 m 2 g −1 , was investigated as a new chemocatalytic approach for vegetable oil hardening and simultaneously producing health-beneficial conjugated linoleic acids (CLA). Time course profiles of (cis-9, trans-11)-; (cis-10, trans-12)-; (trans-10, cis-12)-; (cis,cis)-and (trans, trans)-octadecadienoic isomers (CLAs) as well as the other fatty acids traditionally encountered during the hydrogenation of vegetable oils are presented and discussed under selected process conditions. Preliminary results show that it is possible to tailor characteristics of the hydrogenation catalyst in such way to confer its bi-functional activity: hydrogenation and conjugation isomerisation.

The sulfur effect on conjugated linoleic acid isomer (CLA) formation during the combined hydrogenation/directed isomerization of safflower oil over a bifunctional (hydrogenation and isomerization) highly structured rhodium‐based catalyst (Rh/SBA‐15) was investigated either by direct addition of increased concentrations of 3‐mercapto‐1,2‐propanediol to the reaction medium or by doping Rh/SBA‐15 with the same sulfur‐based compound yielding the sulfur‐doped Rh‐catalyst (S–Rh/SBA‐15). These catalysts exhibited interesting activity, stability, and recyclability.  The maximum CLA contents obtained during the combined reactions with 0, 0.2, 1, 2, 5, and 10 ppm sulfur additions were 73, 99, 131, 110, 105, and 68 mgCLA goil−1, respectively, whereas the amount of harmful trans monoenes remained below 8 %. The safflower oil after partially hydrogenation under the same conditions over S–Rh/SBA‐15 catalyst contained up to 110 mgCLA goil−1. These results showed clear evidence of the sulfur promotion effect on CLA formation during the dual hydrogenation/directed isomerization of safflower oil.  A mechanism for the sulfur promotion of the heterogeneous catalyst Rh/SBA‐15 for the conjugated isomerization activity during hydrogenation/directed isomerization of safflower oil was determined by solid‐state 1H NMR analysis of the fresh and spent catalysts. This was also confirmed by liquid‐state 2H NMR analysis of deuterium‐labeled product aliquots withdrawn throughout the reaction.  The sulfur promotion towards the double bond conjugation of linoleic acid to form CLA isomers could be explained mechanistically through the preferable formation of the more nucleophilic rhodium sulfide (RhSH) over that of the hydride (RhH). However, both types of Rh clusters constituted distinct catalytic sites leading to the formation of hydrogenation as well as conjugated and geometric isomerization products. The lumped kinetics model described the experimental data well and complied simply with the proposed mechanism.

Agro‐based surfactants have one of two hydrophilic or hydrophobic parts of vegetable origin. They can be produced from renewable and readily available resources. Carbohydrate fatty acid esters are non‐toxic, non‐ionic, and biodegradable agro‐based surfactants with applications in the pharmaceutical, cosmetic, and food industries. In this work, the chemical synthesis of agro‐based surfactants through lactose acylation with 1,18‐octadec‐9‐enedioyl chloride (Acyl‐Cl) was investigated at room temperature. The acylation reaction proved to be regioselective to the primary hydroxyl group of the glucose‐moiety in the lactose molecule and was promoted by an excess of lactose to produce higher substituted derivatives. Acyl‐Cl conversion was ∼98 % after 1 h of reaction. The production of monocatenary agro‐based surfactant, mono‐lactose 1,18‐octadec‐9‐enoate, was favoured with a molar ratio lactose/Acyl‐Cl of 1 achieving a yield of 48 % after 20 min. Moreover, production of bolaform agro‐based surfactant, di‐lactose 1,18‐octadec‐9‐enedioate, was favoured with a molar ratio of 3 lactose/Acyl‐Cl with a yield of 33 % after 1 h of reaction. A one‐pot synthesis of agro‐based bolaform surfactant was successfully achieved for the first time in the open literature. Monocatenary and bolaform agro‐based surfactants were isolated by preparative liquid chromatography with high purity according to their chemical structure identification by liquid chromatography coupled to mass spectrometry and 1H nuclear magnetic resonance. Their critical micellar concentration (12–9 μM) determined by fluorescence spectroscopy with pyrene used as a probe, and hydrophilic:lipophilic balance values (10.7–14.2) indicated that monocatenary and bolaform agro‐based surfactants can act as oils in water emulsion.

In this work, a valorization of the starch stemming from downgraded potatoes was approached through the preparation of starch nanoparticles using different physical methods, namely liquid and supercritical carbon dioxide, high energy ball milling (HEBM), and ultrasonication on the one hand and enzymatic hydrolysis on the other hand. Starch nanoparticles are beneficial as a reinforcement in food packaging technology as they enhance the mechanical and water vapor resistance of polymers. Also, starch nanoparticles are appropriate for medical applications as carriers for the delivery of bioactive or therapeutic agents. The obtained materials were characterized using X-ray diffraction as well as scanning and transmission electron microscopies (SEM and TEM), whereas the hydrolysates were analyzed using size exclusion chromatography coupled with pulsed amperometric detection (SEC-PAD). The acquired results revealed that the physical modification methods led to moderate alterations of the potato starch granules’ size and crystallinity. However, enzymatic hydrolysis conducted using Pullulanase enzyme followed by nanoprecipitation of the hydrolysates allowed us to obtain very tiny starch nanoparticles sized between 20 and 50 nm, much smaller than the native starch granules, which have an average size of 10 μm. The effects of enzyme concentration, temperature, and reaction medium pH on the extent of hydrolysis in terms of the polymer carbohydrates’ fractions were investigated. The most promising results were obtained with a Pullulanase enzyme concentration of 160 npun/g of starch, at a temperature of 60 °C in a pH 4 phosphate buffer solution resulting in the production of hydrolysates containing starch polymers with low molecular weights corresponding mainly to P-10, P-5, and fractions with molecular weights lower than P-5 Pullulan standards.

Flax fibres are an agro‐industrial waste available in large quantities in several countries around the world. This resource can be properly used. The goal of this work was to extract lignocellulosic nanosized flax fibres using an environmentally friendly process based on a combination of supercritical carbon dioxide (SC‐CO2) pre‐treatment and enzymatic hydrolysis. Raw flax fibres (RFF) were submitted to a SC‐CO2 pre‐treatment at various temperatures (ie, 70°C and 80°C) and pressures (ie, 20 and 37.7 MPa) for 60 minutes. The enzymatic hydrolysis was performed at 40°C for 24 hours in a pH 4.0 buffer. Cellulase, xylanase, pectinase, and viscozyme were used as hydrolytic enzymes. The as‐received raw flax fibres, SC‐CO2 pretreated flax fibres, and extracted lignocellulosic nanofibrils (LCNF) were characterized by Fourier transformed infrared spectroscopy (FTIR), x‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was shown that the effect of the SC‐CO2 pre‐treatment of flax fibres was two‐fold. It helped to disorganize biomass without changing its chemical composition and it increased access to enzymes to extract LCNF. The FTIR analysis showed no changes in the functional groups after SC‐CO2 pre‐treatment. The XRD characterization revealed that the crystallinity increased with the SC‐CO2 pre‐treatment and LCNF extraction. SEM images showed holes, cracks, and erosion on the surface of the SC‐CO2 pretreated flax fibres (SC‐CO2‐PFF). TEM evidenced the production of nano/micro‐sized fibril and fibril aggregates.

The use of natural compounds to prevent oxidative damage in biological systems is becoming increasingly popular. Blueberries have been of specific interest because of their high antioxidant capacity. Anthocyanins were extracted from berries of Vaccinium angustifolium Aiton and Vaccinium myrtilloides Michaux at 79 °C in acidified ethanol with phosphoric acid as a solvent using a liquid/solid ratio of 10. Extracted anthocyanins were purified on a C‐18 silica‐packed column and analyzed by HPLC coupled to electrospray ionization mass spectrometry. Of the six common anthocyanidins, five were identified in the extracts, namely delphinidin, cyanidin, peonidin, petunidin, and malvidin, while pelargonidin was not found. The free radical scavenging effects of anthocyanins were evaluated using N,N‐dimethyl‐p‐phenylenediamine method as well as their potential to mitigate in vitro low‐density lipoprotein (LDL) oxidative damage. After 6 h of incubation, the oxidation products formation such as that of conjugated dienes, trienes, and hexanal was inhibited up to 60 %. Based on these data, we concluded that anthocyanins from V. angustifolium and V. myrtilloides of Quebec possess the ability to inhibit in vitro LDL oxidation.