Physical properties and oxidative stability of mayonnaises fortified with natural deep eutectic solvent, either alone or enriched with pigmented rice bran.

This article explores the novel use of natural deep eutectic solvents (NaDES) in real food by incorporating them into mayonnaise, either alone or with pigmented rice bran (RB). Results showed that NaDES-fortified mayonnaises could prevent lipid oxidation. Notably, mayonnaises with NaDES2 (betaine:sucrose:water) significantly reduced the production of lipid hydroperoxides, which was maintained to an average of 2.

Characterization of Palm Fatty Acid Distillate, Diacylglycerol Regioisomers, and Esterification Products Using High-Performance Size Exclusion Chromatography.

High-performance size exclusion chromatography (HPSEC) equipped with an evaporative light scattering detector (ELSD) was utilized for characterization of palm fatty acid distillate (PFAD) and its esterified products, with a particular focus on lipid profiles and diacylglycerol (DAG) regioisomers. The separation of triacylglycerol (TAG), DAG, monoacylglycerol (MAG), and free fatty acid (FFA) was achieved through a single 100-Å Phenogel column, coupled with a 2-cm C18 guard, utilizing toluene/acetic acid (100:0.25, v/v) as the mobile phase.

Simultaneous Determination of Vitamin E and γ-Oryzanol in Rice Bran Oil via HPSEC-PDA without Sample Pretreatment.

Vitamin E (tocopherols and tocotrienols) and γ-oryzanol are two minor constituents of rice bran oil (RBO) and are known to be potential bioactive compounds. The content of γ-oryzanol, a unique antioxidant found only in RBO, is a key factor in determining the retail price of the oil. Limitations of conventional HPLC columns for vitamin E and γ-oryzanol analysis are the alteration of these components and the time-consuming need for pretreatment of samples by saponification.

A Simple and Efficient Method for Synthesis and Extraction of Ethyl Ferulate from γ-Oryzanol.

Ethyl ferulate (EF) is a ferulic acid (FA) derivative with high commercial value. It is not found naturally and is mostly synthesized from FA via esterification with ethanol. The present work aimed to synthesize the EF from γ-oryzanol, a natural antioxidant from rice bran oil via acid-catalyzed transethylation at refluxing temperature of ethanol.

Simulation of peak position and response profiles in comprehensive two-dimensional gas chromatography.

Approaches to simulate peak time and intensity profiles of compounds in comprehensive two dimensional gas chromatography (GC × GC) were developed, and which are demonstrated for separation of a mixture of saturated and unsaturated fatty acid methyl esters (FAME) using a range of column sets. The simulation of first and second dimension time (t and t) of FAME relies on use of a Gibbs energy additivity approach to correlate with the structures of FAME. First and second dimension peak standard deviations (σ and σ) of the compounds were further calculated from the t and t data according to the plate height concept which provided good agreement between the predicted and experimental peak widths at half height in one dimension GC (1DGC) with an overall R of 0.

Recovery of γ-Oryzanol from Rice Bran Acid Oil by an Acid-base Extraction Method with the Assistance of Response Surface Methodology.

A rapid and low energy consumption method for the recovery of γ-oryzanol from rice bran acid oil (RBAO), a byproduct of rice bran oil (RBO) refining, is presented. The RBAO was converted to the fatty acid ethyl ester (FAEE) and was used as the starting material. The dissolved γ-oryzanol was separated from the FAEE using an acid-base extraction method with alkaline aqueous ethanol and hexane as extraction media.

Structure and rheology of oleogels made from rice bran wax and rice bran oil.

Structural and rheological properties of oleogels consisting of 0.5-25 wt% rice bran wax (RBX) in rice bran oil (RBO) were explored. RBX was an efficient, thermoreversible oleogelator capable of structuring RBO at concentrations as low as 0.

Ionic liquid phases with comprehensive two-dimensional gas chromatography of fatty acid methyl esters.

New generation inert ionic liquid (iIL) GC columns IL60i, IL76i and IL111i, comprising phosphonium or imidazolium cationic species, were investigated for separation of fatty acid methyl esters (FAME). In general, the iIL phases provide comparable retention times to their corresponding conventional columns, with only minor selectivity differences. The average tailing factors and peak widths were noticeably improved (reduced) for IL60i and IL76i, while they were slightly improved for IL111i.

Gibbs energy additivity approaches to QSRR in generating gas chromatographic retention time for identification of fatty acid methyl ester.

The Gibbs energy additivity method was used to correlate the retention time (t ) of common fatty acid methyl esters (FAMEs) to their chemical structures. The t of 20 standard FAMEs eluted from three capillary columns of different polarities (ZB-WAXplus, BPX70, and SLB-IL111) under both isothermal gas chromatography and temperature-programmed gas chromatography (TPGC) conditions were accurately predicted. Also, the predicted t of FAMEs prepared from flowering pak choi seed oil obtained by multistep TPGC with the BPX70 column were within 1.

Separation of Vitamin E on a 100-Å Phenogel Column.

The effect of π-electrons and hydroxyl group on the separations of vitamin E on a swelling-controlled polystyrene-divinylbenzene (Phenogel) column using toluene/isooctane as the mobile phase was investigated. The effect of the π-electrons was demonstrated in the baseline separation of α-tocopherol and α-tocotrienol on a 100-Å Phenogel column. In addition, baseline separation of α-, (β- + γ-)- and δ-tocopherol could be achieved on this column.

Prediction of gas chromatographic retention times of esters of long chain alcohols and fatty acids.

The linear free energy of solution (DeltaG) relationship (DeltaG=DeltaGo+zdeltaG) for compounds of different carbon atoms (z) in the same homologous series is expanded and modified to cover compounds with two different hydrocarbon side chains. The expanded equation is successfully used to predict the retention times (tR) of standard esters of long chain alcohols and fatty acids of different chain lengths in both isothermal and temperature-programmed gas chromatography (TPGC). Approximately 90% of the 125 predicted tR values have a difference of less than 1.

An alternative approach for the estimation of equivalent temperature in gas chromatography.

The temperature at which the isothermal retention time (tRiso) is equal to the temperature-programmed retention time (tRTPGC) or the isothermal retention index (Iiso) is equal to the temperature-programmed retention index (ITPGC) is defined as the equivalent temperature (Teq). The Teq of one-, two-, three-, and four-step temperature-programmed gas chromatography (TPGC) of unsaturated fatty acid methyl esters (FAMEs) from Chinese mustard seed oil is calculated. All of the tR values obtained at the Teq (tRTeq) are very close to the tRTPGC.

Molecular interconversion behaviour in comprehensive two-dimensional gas chromatography.

Comprehensive two-dimensional gas chromatography (GC x GC) is shown to provide information on dynamic molecular behaviour (interconversion), with the interconversion process occurring on both columns in the coupled-column experiment. The experiment requires suitable adjustment of both experimental conditions and relative dimensions of each of the columns. In this case, a longer column than normally employed in GC x GC allows sufficient retention duration on the second column, which permits the typical plateau-shape recognised for the interconversion process to be observed.