•A method for qualitative analysis of edible oil oxidation using an E-nose was developed.•This rapid and non-invasive method is simpler than classical methods.•The sensitivity of this method is ...excellent for quality control of edible oils.
An electronic nose (E-nose) was used for rapid assessment of the degree of oxidation in edible oils. Peroxide and acid values of edible oil samples were analyzed using data obtained by the American Oil Chemists’ Society (AOCS) Official Method for reference. Qualitative discrimination between non-oxidized and oxidized oils was conducted using the E-nose technique developed in combination with cluster analysis (CA), principal component analysis (PCA), and linear discriminant analysis (LDA). The results from CA, PCA and LDA indicated that the E-nose technique could be used for differentiation of non-oxidized and oxidized oils. LDA produced slightly better results than CA and PCA. The proposed approach can be used as an alternative to AOCS Official Method as an innovative tool for rapid detection of edible oil oxidation.
•Nervonic acid has the identified and potential biological function to brain health.•Various sources and production methods of nervonic acid is the crucial basis for its application.•For nervonic ...acid, further research on its mechanism of action is warranted.
Nervonic acid (NA) has attracted considerable attention because of its close relationship with brain development. Sources of NA include oil crop seeds, oil-producing microalgae, and other microorganisms. Transgenic technology has also been applied to improve the sources and production of NA. NA can be separated and purified by urea adduction fractionation, molecular distillation, and crystallization. Studies on NA functionality involved treatments for demyelinating diseases and acquired immunodeficiency syndrome, as well as prediction of mortality due to cardiovascular diseases and chronic kidney disease. This mini review focuses on the sources, production, and biological functions of NA and provides prospective trends in the investigation of NA.
Headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) analysis combined with 'relative odour activity value (ROAV)' was used to monitor changes in key volatile ...compounds in peanut oil, soybean oil, rapeseed oil, and linseed oil during ambient storage. Volatile composition and oxidation process were compared among edible oil samples. The differences in the volatile contents of edible oils led to their characteristic flavour. Aldehydes featured a relatively high content and low odour threshold and mainly contributed to the flavour of edible oils. The key flavour compounds included pentanal, hexanal, octanal, nonanal, trans-2-heptenal, and benzaldehyde, which are important oxidative degradation products of oleic acid and linoleic acid. The formation of key volatile oxidation compounds was affected by different oxidation processes during ambient storage. Certain aldehydes increased with oxidation level, whereas other aldehydes initially increased then decreased. Correlation analysis showed that the concentrations of several volatile compounds progressively increased during oxidation. The key volatile oxidation compounds formed during oil storage at ambient temperature are partly different from those generated at high temperatures. Volatile oxidation compounds can be a marker for monitoring the oxidation degree of edible oils during ambient storage.
The physicochemical, functional and pasting properties of whole flours from pinto bean, lima bean, red kidney bean, black bean, navy bean, small red bean, black eye bean, mung bean, lentil and ...chickpea were investigated. Significant differences in physicochemical characteristics and functional properties were observed (P < 0.05). Bulk densities, water absorption indices, water solubility indices, oil absorption capacities, emulsion activities, and emulsion stabilities ranged from 0.543 g/mL to 0.816 g/mL, 4.09 g/g to 6.13 g/g, 19.44 g/100 g to 29.14 g/100 g, 0.93 g/g to 1.38 g/g, 61.14%–92.20%, and 84.15%–96.90%, respectively. Phaseolus legume flour exhibited higher water absorption capacity, oil absorption capacity, emulsion activity, and emulsion stability compared with other kinds of legume flour. Pasting properties were significantly different (P < 0.05). Pasting temperatures and the peak, final, and setback viscosities of the flours ranged from 73.2 °C to 83.0 °C, 96.2 RVU to 216.8 RVU, 118.5 RVU to 243.8 RVU, and 28.3 RVU to 103.2 RVU, respectively.
•Physicochemical and functional properties of different legume flours were studied.•Significant differences were in physicochemical and functional properties of legume flours.•Functional properties of flours depend on ratios of protein to starch and other components.•Phaseolus legumes flours had high WAC, OAC, emulsifying activity and emulsion stability.
To destabilize the emulsion during aqueous extraction processing (AEP) and improve oil yield of walnuts, sugar-aided aqueous extraction (SAAE) with optimized extraction parameters was explored. ...Demulsification mechanism using Span 20 at acidic pH during SAAE was discovered. Highest walnut oil yield (90.74%) was obtained at sugar solution of 1 mol/L, solvent-to-sample ratio of 4:1, and extraction temperature of 85 °C, extraction time of 60 min, 1.9 g/100 g Span 20, and pH 6.0. Span 20 significantly improved walnut oil yield by allowing the release of oil and decreasing the emulsion fraction. This result may have been caused by the dominance of Span 20 at the interface, resulting in unstable emulsions. No evident change was found in the walnut protein, suggesting that the obtained protein can be reclaimed.
•The proposed method achieved high oil yield (90.74%).•Extraction time was reduced by the proposed method.•Proteins recovery was intact during SAAE.•The effect of Span20 was proved by microscopic and droplet size analysis.•Sugar solution could be reused.
Fats and oils are essential food components. Their quality and safety pose major concerns for consumers and food producers because of factors such as oxidation and rancidity, excessive levels of ...trans fatty acid (TFA), and widespread adulteration. Thus, a rapid and easy-to-use technique must be exploited for quality parameter evaluation and monitoring to ensure the edibility, safety, and quality of fats and oils. In the last decades, Fourier transform infrared (FTIR) spectroscopy has shown great potential in analyzing fats and oils given its speed and simplicity. FTIR-based analytical techniques for common intrinsic quality parameters, including peroxide value, free fatty acid, moisture, TFA, iodine value, as well as oxidation stability, adulteration, and classification of various fats and oils, are summarized in this review. The advantages and disadvantages of selected infrared spectral accessories and sample preparation and spectral processing methods are highlighted. The prospects and reformative aspects for future application of the FTIR technique in the field of fats and oils are also discussed. This review may serve as a basis for applying FTIR not only in future research but also in the fat and oil industries.
A degumming protocol, which utilized sodium chloride solution (SCS), was developed to remove phospholipids (PLs) and retain the flavor of fragrant rapeseed oil (FRO). The composition of PLs, ...physicochemical characteristics, and flavor profile of FRO were determined to assess the degumming effect of SCS. The PL removal rate of the finally optimized degumming procedure (SCS concentration of 3%, w/w) was 90.7%, which was superior to that of water degumming (86.3%). Moisture, total phenolic, and phytosterol contents indicated the high quality of the oils subjected to 3% SCS degumming. Additionally, FRO produced via the developed method had a bright color, and its flavor was well retained. Moreover, the PLs obtained via 3% SCS degumming exhibited better emulsifying capability than commercial lecithin, suggesting that the recovered PLs could be reclaimed. Therefore, the proposed technology is economical and effective. It has a promising prospect in industrial FRO degumming.
•The 3% SCS degumming achieved a high efficiency for the removal of PLs (90.7%).•The degummed FRO showed high-quality physicochemical characteristics and well retained its flavor.•The effect of SCS was proved by PL composition analysis.•PLs obtained by 3% SCS degumming had better emulsifying capability.•It is an economical, sustainable and environmental friendly refining method.
2019
A new method for the determination of the induction period (IP) of walnut oil through polyethylene-film-based Fourier transform infrared (PE-FTIR) spectroscopy was developed. The IP value was ...used to represent the oxidation stability of walnut oil. The characteristic infrared spectrum peaks at 3008, 1654, 914, and 723 cm
−1
changed significantly as the IP value decreased. The prediction model was established on the basis of these changes. The optimal partial least squares model was established under the following conditions: constant, original spectra, no smoothing, and wavelength range of 1640–440 cm
−1
. The calibration set of the model provided a coefficient of determination (
R
2
) of 0.9847 and a root mean error of calibration of 3.38. The
R
2
and the root mean square error of prediction for the validation set were 0.9878 and 2.32, respectively, and were 0.9948 and 3.61 for the blind sample validation set, respectively. In precision evaluation, the standard deviation and coefficient of variation of the predicted values were 4.13 and 4.19%, respectively. The present results indicated that the polyethylene-FTIR method for analyzing the IP value of walnut oil was simple and rapid and could be used as a highly effective alternative to the traditional determination method.
The objective of this study was to investigate the effects of linolenic acid (LA) on oxidation stability of rapeseed oils. Four kinds of rapeseed were harvested by unified cultivation and management ...in the same geographical conditions, and then four rapeseed oils with different contents of LA were obtained. The effects of linolenic acid and antioxidants (tocopherols and phytosterols) on oxidation stability of rapeseed oils were evaluated. Results showed that rapeseed oil with 5.9% LA was the most stable among four rapeseed oils, followed by commercial rapeseed oil, rapeseed oil with 8.4% LA and rapeseed oil with 10.8% LA. The oxidation stability was negatively correlated with the contents of LA (r = − 0.931,
p
< 0.01), the polyunsaturated fatty acids (r = − 0.932,
p
< 0.01), and unsaturated fatty acids (r = − 0.766,
p
< 0.05). It had no correlation with tocopherols and phytosterols (
p
> 0.05). In addition, according to the European Union Standards, shelf-life of four rapeseed oils was longer than 30 days in the shelf-life test. Therefore, increasing the LA content in rapeseed oils can be considered as an efficient approach to solve the problem of insufficient LA intake globally.
Background
Cold plasma (CP) can be defined as partially or wholly ionized gas carrying myriads of highly reactive products, such as electrons, negative ions, positive ions, free radicals, excited or ...non-excited atoms, and photons at ambient temperature. It is generated at 30–60°C under atmospheric or reduced pressure (vacuum). In contrast to thermal plasma, it requires less power, exhibits electron temperatures much higher than the corresponding gas (macroscopic temperature), and does not present a local thermodynamic equilibrium. Dielectric barrier discharges (DBD) are one of the most convenient and efficient methods to produce CP.
Scope and approach
Cold plasma technology has the potential to replace traditional agri-food processing purification methods because of its low energy requirements and flexible system design. CP technology works by reducing bacteria levels and removing pests and mycotoxins from your produce at harvest. It can also catalyze physiological and biochemical reactions and modify materials. It can meet microbial food safety standards, improve the physical, nutritional, and sensory characteristics of the products, preserve unstable bioactive compounds, and modulate enzyme activities. This manuscript also discusses the quality characteristics of food components before/after CP treatment.
Key findings and conclusion
In the past decade, CP treatments of food products have experienced increased popularity due to their potential contributions to non-thermal food processing. There is no doubt that CP treatment is a flexible approach with demonstrated efficacy for controlling many risks across food and agricultural sustainability sectors. In addition, CP technologies also can be applied in food-related areas, including modification of chemical structures and desensitization treatments. There is a need to fully assess the benefits and risks of stand-alone CP unit processes or their integration as a processing chain as soon as the economic, ecological, and consumer benefits and acceptability are considered.
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