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Vegetable fats and oils are prone to contamination by mineral oil hydrocarbons due to the lipophilic and ubiquitous character of the latter. As the aromatic fraction of these hydrocarbons, MOAH, is associated with carcinogenicity, mutagenicity, and detrimental effects on foetal development, finding strategies to limit or reduce their contamination is highly relevant. Deodorisation (i.e. a refining step) has shown the ability to remove MOAH < C25 in vegetable fats and oils, but there is little information about the structures removed. Therefore, the present study investigated the impact of deodorisation conditions on the removal of different structures of MOAH in spiked coconut oil. An inscribed central composite design was built with time and temperature as variables (0.5-4h, 150-240 °C), while pressure (3 mbar) and steam flow (1 g water/g oil per hour) were kept constant. The analysis of MOAH in the oil was performed using a fully automated liquid chromatography coupled with two parallel comprehensive two-dimensional gas chromatography systems with flame ionisation and time-of-flight mass spectrometric detection. Response surfaces plotting the MOAH loss according to time and temperature were built for different MOAH fractions. The latter were defined based on the number of aromatic rings (>3 or ≤3) and the number of carbon atoms present (C16-C20, C20-C24, C24-C35, C35-C40). It was found that at 200 °C, compounds < C24, including weakly alkylated triaromatics, could be reduced to below the limit of quantification, while at 230 °C, it was possible to remove >60% of the C24-C35 fraction, including pentaromatics of low alkylation. [ABSTRACT FROM AUTHOR]

Cold-pressed moringa, milk thistle, and jujube seed oils were investigated in terms of their characteristic profiles, thermal properties, and oxidative stability. The findings proved that the extracted oils were characterized by high nutritional values, which encourages their use in various fields. Results showed significant differences between the obtained oils. Overall, jujube seed oil exhibited the best quality parameters, with acidity equal to 0.762 versus 1% for the moringa and milk thistle seed oils. Milk thistle seed oil showed absorbance in the UV-C (100–290 nm), UV-B (290–320 nm), and UV-A (320–400 nm) ranges, while the moringa and jujube seed oils showed absorbance only in the UV-B and UV-A ranges. Concerning bioactive compounds, jujube seed oil presented the highest content of polyphenols, which promoted a good scavenging capacity (90% at 10 µg/mL) compared to the moringa and milk thistle seed oils. Assessing the thermal properties of the obtained oils showed the presence of four groups of triglycerides in the moringa and milk thistle seed oils, and two groups of triglycerides in the jujube seed oil. The thermograms were constant at temperatures above 10 °C for milk thistle seed oil, 15 °C for jujube seed oil, and 30 °C for moringa seed oil, which corresponded to complete liquefaction of the oils. The extinction coefficients K232 and K270, monitored during storage for 60 days at 60 °C, proved that jujube seed oil had the highest polyphenols content and was the most stable against thermal oxidation. [ABSTRACT FROM AUTHOR]

Seven mango seeds of Ivorian varieties, that is, Amelie, Kent, Keitt, Brooks, Palmer, Dadiani, and Djakoumankoun were collected from Northern Ivory Coast as wastes from local processing factories and local markets; their kernels were then quickly separated and sun‐dried to ensure lipases inactivation. This study was carried out to elucidate (1) the variability in the proximate composition (protein, ash, and fat content) of the so‐obtained kernels and (2) the characteristics of the extracted fat including acidity, peroxide value, unsaponifiable matters, phospholipid content, iodine value, fatty acid (FA), and triacylglycerol (TAG) composition, sterol content, oxidative stability, color, and carotenoid content. It was found that the fat content ranged from 4.9% to 9.6% (dry matter) depending on the variety. Whatever the variety, oleic (O, 35.9%–47%) and stearic acid (St, 30.3%–48.3%) were the most abundant FA. A wide range of variation in TAG composition was however observed: the major were StOSt (23.9%–45.9%), StOO (15.5%–25.8%), and StLSt (10.4%–12.5%). A classification of the seven varieties based on their FA, TAG, and sterol content, was established using multivariate analysis: principal component analysis (PCA) and cluster analysis (CA). According to their main FA and TAG, the seven varieties may be grouped into four clusters: cluster I = Amelie, cluster II = Keitt, Palmer, and Kent, cluster III = Brooks and Dadiani and, cluster IV = Djakoumankoun. [ABSTRACT FROM AUTHOR]

Mango (Mangifera indica L.) seeds is an interesting source of fat, rich in stearic (St) and oleic (O) acid with three major triacylglycerols (TAG): StOSt, StOO, and StLSt. The kernel fat content and quality depend however on the varieties and their origin. The objective of this study was to investigate the crystallization and polymorphic behavior of mango kernel fat extracted from three selected Ivorian varieties which differ in terms of TAG composition: Kent (KT), Djakoumankoun (DN) and Brooks (BR). The isothermal crystallization behavior was examined at 15 and 20°C by pulsed nuclear magnetic resonance, differential scanning calorimetry, x‐ray diffraction (XRD) and polarized light microscope. Under static conditions, DN crystallized faster, followed by BR, then KT. At 15°C, an unusual evolution was observed for both DN and BR, which can be explained by a melt‐mediated polymorphic transition from α into more stable forms. Using a differential scanning calorimetry (DSC) stop‐and‐return technique, different crystallization behaviors were also observed. Isothermal XRD experiments confirmed that the kinetics of the polymorphic transformation was different within the three samples, even if the three fats were β‐3L‐tending. At 15°C, KT transformed from liquid state to stable form without passing through α‐form, while DN and BR crystallized first into α‐from which transformed further to β′, then into stable β‐form. At 20°C, DN and BR crystallized directly from liquid to β′, which later transformed into β‐form while KT did not crystallize under the same conditions. The huge differences observed result from the differences in the TAG profiles, mainly in the StOO and StOSt content. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the potential of applying enzymatic interesterification (EIE) to produce new healthy zero-trans high vitaminic content margarine fats, based on rapeseed oil (RO) only, with a specific focus on process-induced contaminants: the dialkylketones. Three blends made of RO and fully hydrogenated rapeseed oil (60:40, 70:30 and 80:20 wt:wt%) were considered. Compositional and melting properties, polymorphic behavior, appearance and textural characteristics were compared before and after interesterification. Interesterification improved both functional and textural characteristics. Enzymatic interesterification produced fats which presented similar triacylglycerol profile and physicochemical properties as the chemically interesterified one (CIE), however, preserving more tocopherols and without forming dialkylketones (process-induced contaminants). On the contrary, it was shown that after CIE, dialkylketones were formed: C18:1–C18:1 and C18:1–C18 chain-lengths being the major ones, and interestingly, their amount increased with the unsaturation in the blends. Our results indicate the great potential of enzymatic interesterification to produce new healthy fats entirely based on rapeseed oil. This study provides valuable information for the food industry, showing EIE as cutting-edge sustainable technology.