Journal of the American Oil Chemists Society最新文献

Vegetable oils are promoted as a base oil for automobile lubricants due to increased concerns about the environmental damage caused by synthetic and mineral oils-derived lubricants. Coconut oil exhibits excellent tribological properties but poor cold flow properties. This work investigates the effect of the addition of palm oil methyl ester (POME), obtained from the transesterification of palm oil, on coconut oil by blending it in three proportions with varying volumes and evaluating for lubricant properties namely tribological properties, rheological properties, thermal properties, chemical properties and corrosion and oxidative stabilities. Fatty acid composition are evaluated for the base oil and the blends. The findings show that the addition of POME improves the base oil's pour point and reduces friction and wear. The corrosion test shows only slight tarnishing of copper strips, while the HOOT and chemical tests indicate appreciable resistance to oxidation. Therefore, this blended mixture has the potential to be a viable bio-lubricant alternative to traditional mineral-based oils.

The conversion of triacylglycerols in edible oils into diacylglycerols (DAGs) is of great significance for obtaining products with health benefits. Camellia seed oil (C-oil), which is rich in oleic acid and linoleic acid, is an excellent raw material for the production of DAGs. In this study, single factor optimization experiments were carried out for hydrolysis and esterification respectively. Using Lipozyme® RM IM as catalyst, the maximum percent of C-oil hydrolysis reached 87.14% at the reaction temperature of 60°C, reaction time of 24 h, water content of 30% and enzyme addition amount of 4%. The maximum content of camellia seed oil diacylglycerol (C-DAG) reached 62.49% under the conditions of Lipozyme® RM IM as catalyst, vacuum system, 3% enzyme addition, 2% water addition, reaction temperature of 50°C and substrate molar ratio of free fatty acid to glycerol of 1:1. The high content of DAG was obtained by a coupled method, which eliminated the purification steps and reduced production costs. C-oil and C-DAG have been characterized by GC, TG, DSC, and GC-IMS. Our results showed that the enzymatic coupling method did not affect the structural of the substances, but did affect the crystallization and melting properties of the oils. Moreover, the taste of C-DAG was more delicate than C-oil. Finally, the reaction mechanism was analyzed using FTIR spectroscopy, revealing that C-oil was primarily hydrolyzed into free fatty acids. C-DAG exhibited ester C-O stretching vibrations in the range 1280–1030 cm⁻¹, indicating successful esterification reaction between camellia seed oil free fatty acids (C-FFAs) and glycerol catalyzed by lipases.

This study aimed to evaluate the effect of microwave power and duration on French fries using palm olein. The deep-fat frying was served as a control. The microwave frying of French fries was conducted at low (100 W), medium (600 W), and high (1000 W) for 1, 3, and 5 min. The physicochemical properties of French fries and the quality of palm olein were analyzed. The French fries microwaved at 600 W for 3 min showed comparable hardness (300 g), cohesiveness (0.76), springiness (3.5 mm), adhesion (0.3 mJ), and water activity (0.88 A_w) to deep-fat frying. The palm olein demonstrated lower peroxide and para-anisidine values in microwave frying; while deep-fat frying had lower total polar compounds in frying oil and lower oil content in oil extracted from French fries. Nevertheless, the high oxidation stability in terms of peroxide and para-anisidine value in frying oil from microwave frying showed its potential as an alternative frying technique to deep-fat frying.

Hot-pressed fragrant rapeseed oil (HFRO) is a traditional edible oil in China, prized for its special flavor, which includes fresh, spicy, pungent and roasted fragrance. The fresh fragrance is mainly brought by aldehydes, ketones, esters, alcohols and other substances produced by fat oxidation. The pungent fragrance is mainly caused by thiocyanates and isothiocyanates produced by the degradation of glucosinolates. Roasting aroma is usually brought by pyrazines and furans produced by Maillard reaction. Both the composition of the rapeseed and the processing techniques employed are critical in shaping these flavor components. An optimal processing temperature for HFRO is around 150°C. Rapeseed varieties with higher glucosinolates content are preferred for producing oils with a pronounced spicy, whereas those with lower glucosinolates levels are suitable for a stronger roasted aroma. The moisture content of the rapeseed should ideally be maintained between 10% and 15% to optimize flavor development. This study elucidates the primary pathways for volatile compound production in HFRO and discusses future prospects and research directions for the enhancement of rapeseed oil, offering a scientific foundation for the modern processing and quality control of rapeseed oil.

Ferritin is a naturally occurring iron storage protein. Leguminous ferritins exhibit unique structural features, including diverse subunit composition and an extension peptide, which contribute to superior thermal stability compared to animal ferritins. The high iron content, remarkable effectiveness, low risk of oxidative damage and thermal stability make the leguminous ferritin an attractive candidate for iron supplementation. Moreover, apoferritin is an excellent nanosized carrier for encapsulating bioactive compounds due to its inherent inner cavity, water solubility, biocompatibility, and reversible self-assembly behavior. However, the harsh condition during encapsulation by unmodified ferritins may cause damage to sensitive bioactive compounds. Thus, different processing methods are employed to alter the leguminous ferritin structures, including chemical, enzymatic, mild heat treatments, and nonthermal processing to achieve gentler encapsulation conditions for a wide range of bioactive compounds. Another challenge is to improve the stability of leguminous ferritin to withstand gastric digestion. The degradation of ferritin by proteases may lead to premature release of bioactive compounds. Recent works demonstrated that certain phenolic compounds such as proanthocyanidin-induced protein association, thereby enhancing digestive stability of ferritins, leading to a sustained release and a potentially greater bioavailability of bioactive compounds. Leguminous ferritin also has the potential to serve as a stabilizer for the Pickering emulsion, where the hydrophilic and hydrophobic compounds can be encapsulated in the ferritin nanocages and oil phase, respectively. The release and absorption of bioactive compounds in encapsulates and emulsions will need to be further demonstrated through in vivo studies.

Bioparaffins, derived from soybean oil, hold significant potential as sustainable alternatives to mineral waxes in various industrial applications. However, to fully exploit their benefits, it is necessary to engineer their performance and properties. In this work, a non-linear partial least squares (PLS) algorithm was used to relate the melting profiles obtained via differential scanning calorimetry (DSC) to the chemical composition determined by gas chromatography (GC) of simple and binary mixtures of (partially) hydrogenated samples. This model was used to determine the composition of a bioparaffin to mimic the thermal and textural properties of commercial mineral paraffin. This innovative approach allows for broader adoption in industries seeking sustainable alternatives to petroleum-based waxes.

Soybean is one of the most economically important crops in the United States. Produced for its oil and protein concentration, it is readily utilized in food products for both human and livestock consumption. Since soybean was first cultivated in the United States, increased yield has been the driving factor in breeding efforts. Though yield and oil have been observed to be positively correlated, protein concentration is negatively correlated with both. An increased effort has been underway recently to produce high-yielding cultivars that have both elevated oil and protein concentration. This has been accomplished utilizing molecular markers associated with quantitative trait loci (QTL) for both traits. To assist in this effort, more information on QTL associated with quality traits is required. In this study, 180 F_4:6 recombinant inbred lines (RILs) segregating for protein, oil, and fatty acids were produced from a cross between TN12-4098 and TN13-4303. These lines were grown across three locations in Tennessee: Research and Education Center at Milan (RECM), Highland Rim Research and Education Center (HRREC), and East Tennessee Research and Education Center (ETREC) in 2018 and 2019. Sixteen QTL were found for protein, oil, linolenic acid, and meal protein concentration. Of these identified QTL, six were novel. Developing molecular markers associated with these QTL will assist in breeding efforts to produce high-quality elite soybean cultivars that meet the demands of both farmers and consumers.

The growing interest in the rapid measurement of seed ingredients using single-kernel NIR (SKNIR) spectroscopy as a nondestructive measurement technique allows fast analysis of sample seed variance that can have effects on breeding and end-use processing. Flax (Linum usitatissimum), an oilseed crop grown in the Northwest United States and worldwide, is highly beneficial for human health, food, and fiber. Its health benefits include its high protein and omega-3 fatty acids content. Therefore, seed composition profiles are an important aspect of breeding. The goals of this research were the development of single seed NIR calibration models for protein, oil, and weight of intact flax seeds. In this study, SKNIR spectroscopy was used on a diverse set of flax accessions comprising of 306 samples to create prediction models on a custom built SKNIR instrument. Spectra data and reference protein, oil, and weight were used to build partial least squares (PLS) models. Calibration models provided reasonable prediction of these traits and could be used for screening purposes. PLS statistics were oil (R² = 0.82, SEP = 1.72), weight (R² = 0.74, SEP = 0.71), and protein (R² = 0.62, SEP = 0.96) for validation data sets comprising of one-third of the total samples. In conclusion, prediction models showed that SKNIR spectroscopy could be a very beneficial nondestructive technique to determine oil and weight as well as rapid screening of protein in single flax seeds while not requiring extensive preparation as compared to traditional techniques.

The microencapsulation of vegetable drying oils is an established strategy to develop smart coatings with self-healing properties. The literature has mostly focused on evaluating linseed oil (LO) and tung oil (TO) as self-healing agents. There is a lack of studies regarding the application of other drying oils in smart coatings and a comparison between different vegetable oils as self-healing agents has yet to be carried out. In this work, the self-healing potential of different seed oils was assessed in terms of their drying and anticorrosive properties. The investigation was focused on chia oil (CO), dehydrated castor oil (DCO), LO, and TO. Drying times were assessed under different cobalt (Co) drier contents. Drying kinetics was carried out by monitoring changes in viscosity with time and following the evolution of infrared spectra during drying. Barrier properties of the polymerized oil-based coatings were assessed by electrochemical impedance spectroscopy of carbon steel coated samples during immersion in 0.1 mol/L NaCl solution. It was found that the type of oil and concentration of drier play an important role on favoring the self-healing effect. The concentration of 0.2 wt% Co was found optimum for encapsulation to accelerate self-healing, as oils dry up to three times faster in comparison with the lowest drier content studied (0.025 wt% Co). TO obtained the best drying properties, with set-to-touch times around 1 h and rapidly forming a tack-free film, however, TO coatings ended up being extremely cracked, which compromised its barrier properties. LO obtained the slowest drying, while CO and DCO exhibited intermediate drying between TO and LO. DCO showed the best anticorrosive properties among investigated oils, as its coating was the only one that did not show any decrease in impedance with time, whereas TO and LO coatings presented a decrease in up to one order of magnitude in impedance. Overall, the good drying and barrier properties of DCO strongly stimulate its use as feedstock for self-healing coatings. Results are discussed in terms of fatty acid composition and oxidative polymerization mechanisms. Conclusions help with the selection of seed oils as self-healing agents that can further extend the lifetime of anticorrosive coatings.

Structured lipid diacylglycerol (DAG) synthesis employing bubble column reactor (BCR) is a recent and promising approach used to replace the conventional stirred tank reactor for upscaling purpose. BCR offers great economic benefits in the long run. In the present study, a screened Lecitasse® Ultra (LU) lipase was immobilized (LXTE-LU) and used repetitively in both BCR and stirring system reactor (STR) to catalyze the glycerolysis of flaxseed oil for the preparation of DAG. The BCR system was found to prolong the lipase shelf life, maintaining 69% of catalytic activity after 10 cycles. The reaction products were purified by molecular distillation to obtain DAG-40 and DAG-80. Monitoring of processing contaminants and phytonutrients during the heat treatment of flaxseed oil and flaxseed oil DAG products revealed that prolonged heat treatment significantly increased glycidyl esters levels while short-term stir-frying did not significantly affect the levels of processing contaminants levels. However, prolonged heat treatment destroyed phytonutrients. Meanwhile, the oxidation kinetic study showed that the DAG samples fitted well with the zero-order reaction kinetic model, and the oxidation rate of DAG was lower than that of flaxseed oil. Additionally, the antioxidant effect increased with higher DAG content, indicating that DAG could effectively retard lipid oxidation and improve the stability of the oxidation process. These stabilities suggest the potential application of polyunsaturated DAG in food processing systems.