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The triacylglycerol (TAG) matrix of argan oil (AO) bodies (AOB) along with the TAGs of AO extracted from the same kernels using an organic solvent, were identified and quantified using the ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Generally, both samples showed a similar TAGs profile but AO found to have three extra TAGs in low amount. In total 23 and 26 different TAGs were identified in AOBs and AO, respectively. The most abundant TAGs were OOL, POO, OOO, and POL in both samples. Furthermore, oleic acid, linoleic acid, and palmitic acid were the major fatty acids in both AOBs and AO. To the best of our knowledge, this is the first research that studied the TAGs matrix of an oil body revealing no major difference between the TAGs profile protected by the AOBs membrane and the oil extracted from the whole seed. PRACTICAL APPLICATION: Seed and kernels oil bodies emulsion tend to be the new source of emulsified oil in food and cosmetic industries. However, before replacing a product with another, we have to make sure that the new alternative can offer better or at least similar benefits. Our results showed that the triacylglycerols (TAGs) matrix and the argan oil (AO) share the same TAGs profile with a relatively close percentage. Therefore, AO bodies can be the perfect pre-emulsified oil for some food products like sauces and creams., (© 2019 Institute of Food Technologists®.)

Purification of triglycerides from fully hydrogenated palm kernel oil (FHPKO) and fully hydrogenated coconut oil (FHCNO) was performed by a chromatographic method. Lipid composition, thermal properties, polymorphism, isothermal crystallization behaviour, nanostructure and microstructure of FHPKO, FHPKO-triacylglycerol (TAG), FHCNO and FHCNO-TAG were evaluated. Removal of minor components had no effect on triglycerides composition. However, the presence of the minor components did increase the slip melting point and promote onset of crystallization. Furthermore, the thickness of the nanoscale crystals increased, and polymorphic transformation from β' to β occurred in FHPKO after the removal of minor components, and from α to β' in FHCNO. Sharp changes in the values of the Avrami constant K and exponent n suggested that the presence of minor components changed the crystal growth mechanism. The PLM results indicated that a coarser crystal structure with lower fractal dimension appeared after the removal of minor components from both FHPKO and FHCNO., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Oil migration and fat recrystallization in fat-structured food materials can result in significant deterioration in food quality. Consequently, it is important to monitor and quantify the diffusivities of the migrants in fat crystal network. The diffusion coefficients of Nile red dye in liquid oils through fully hydrogenated palm kernel oil (FHPKO)/triolein (OOO) and fully hydrogenated soybean oil (FHSO)/triolein (OOO) systems were evaluated by the fluorescence recovery after photobleaching (FRAP) method. The effective diffusion coefficients (D eff ) and mobile fraction (M f ) increased with the decrease of solid fat contents (SFC), with the changes of microstructure from more densely to slightly larger packed clusters for both FHPKO/OOO and FHSO/OOO systems. In addition, microstructural parameters of these systems were estimated by the image analysis. The results showed that the diffusion of dye and liquid oil was affected by the microstructure. The higher D eff was associated with lower fractal dimensions, larger crystal thickness, and larger average particle sizes. Finally, higher-permeability coefficients were calculated according to Darcy's Law, and it was significantly correlated to the D eff .

Human milk fat substitutes (HMFSs) were synthesized by lipozyme RM IM-catalyzed acidolysis of chemically interesterified palm stearin (mp = 58 °C) with mixed FAs from rapeseed oil, sunflower oil, palm kernel oil, stearic acid, and myristic acid in a solvent-free system. Response surface methodology (RSM) was used to model and optimize the reactions, and the factors chosen were reaction time, temperature, substrate molar ratio, and enzyme load. The optimal conditions generated from the models were as follows: reaction time, 3.4 h; temperature, 57 °C; substrate molar ratio, 14.6 mol/mol; and enzyme load, 10.7 wt % (by the weight of total substrates). Under these conditions, the contents of palmitic acid (PA) and PA at sn-2 position (sn-2 PA) were 29.7 and 62.8%, respectively, and other observed FAs were all within the range of FAs of HMF. The product was evaluated by the cited model, and a high score (85.8) was obtained, which indicated a high degree of similarity of the product to HMF.

Six rectangular block all beef tallow (BT)-based and all palm oil (PO)-based model shortenings prepared on a laboratory scale, respectively denoted BTMS and POMS, were stored under temperature fluctuation cycles of 5-20 °C until granular crystals were observed. The lipid composition and thermal, polymorphic, and isothermal crystallization behaviors of the granular crystals and their surrounding materials separated from BTMS and POMS, respectively, were evaluated. The changes of nanostructure including the aggregation of high-melting triacylglycerols (TAGs) and polymorphic transformation from β' form of double chain length structures to complicated crystal structures, in which the β and β' form crystals of triple and double chain length structures simultaneously coexist, had occurred in granular crystals compared with surrounding materials, whether in BTMS or in POMS. Consequently, a slower crystallization rate appeared in granular crystal parts of both model shortenings noted above, which would yield larger and fewer crystals indicated by the Avrami model analysis that would further aggregate to form large granular crystals.