Cold pressed pumpkin seed oil fatty acids, carotenoids, volatile compounds profiles and infrared fingerprints as affected by storage time and wax-based oleogelation.

BACKGROUND: Pumpkin seed and sunflower oil are rich in bioactive compounds, but are prone to oxidation during storage. Their fatty acids, carotenoid and volatile compounds and their Fourier-transform infrared (FTIR) profiles were studied during 8 months storage in order to assess the overall quality, but also to assess the impact of the oleogelation as conditioning process. RESULTS: The fatty acids methyl esters were analyzed by gas chromatography-mass spectrometry (GC-MS). The linoleic acid was the most abundant in the oils (604.6 g kg-1 in pumpkin and 690 g kg-1 in sunflower), but also in oleogels. Through high-performance liquid chromatography (HPLC), lutein and ß-carotene were determined as specific carotenoid compounds of the pumpkin seed oil and oleogel, in a total amount of 0.0072 g kg-1 . The volatile compounds profile revealed the presence of alpha-pinene for the pumpkin seed oil and oleogels and a tentative identification of limonene for the sunflower oil. Hexanal was also detected in the oleogels, indicating a thermal oxidation, which was further analyzed through infrared spectroscopy. CONCLUSIONS: During 8 months storage, the decrease of polyunsaturated fatty acid total amount was 5.72% for the pumpkin seed oil and 3.55% for the oleogel, while in the sunflower oil samples of 2.93% and 3.28% for the oleogel. It was concluded that oleogelation might protect specific carotenoid compounds, since the oleogels displayed higher content of ß-carotene at each storage time. Hexanal and heptanal were detected during storage, regardless of the oil or oleogel type. FTIR analysis depicts the differences in the constituent fatty acids resulting due to thermal oxidation or due to storage. © 2022 Society of Chemical Industry.

More sustainable vegetable oil: Balancing productivity with carbon storage opportunities.

Intensive cultivation and post-harvest vegetable oil production stages are major sources of greenhouse gas (GHG) emissions. Variation between production systems and reporting disparity have resulted in discordance in previous emissions estimates. The aim of this study was to assess global systems-wide variation in GHG emissions resulting from palm, soybean, rapeseed and sunflower oil production. Such an analysis is critical to understand the implications of meeting increasing edible oil demand. To achieve this, we performed a unified re-analysis of life cycle input data from diverse palm, soybean, rapeseed, and sunflower oil production systems, from a saturating search of published literature. The resulting dataset reflects almost 6000 producers in 38 countries, and is representative of over 71% of global vegetable oil production. Across all oil crop systems, median GHG emissions were 3.81 kg CO2e per kg refined oil. Crop specific median emissions ranged from 2.49 kg CO2e for rapeseed oil to 4.25 kg CO2e for soybean oil per kg refined oil. Determination of the carbon cost of agricultural land occupation revealed that carbon storage potential in native compared to agricultural land cover drives variation in production GHG emissions, and indicates that expansion of production in low carbon storage potential land, whilst reforesting areas of high carbon storage potential, could reduce net GHG emissions whilst boosting productivity. Nevertheless, there remains considerable scope to improve sustainability within current production systems, including through increasing yields whilst limiting application of inputs with high carbon footprints, and in the case of palm oil through more widespread adoption of methane capture technologies in processing stages.

Hepatic fatty acids profile, oxidative stability and egg quality traits ameliorated by supplementation of alternative lipid sources and milk thistle meal.

This study assessed the effects of different levels of milk thistle (Silybum marianum) meal (MTM) on egg quality traits, oxidative stability, blood biochemical parameters and liver health indices in laying hens receiving diets supplemented with lipid from different sources. For this purpose, Leghorn laying hens (Hy-Line W-36) were randomly assigned to 12 experimental treatments with eight replicates of five birds each. Dietary treatments consisted of four dietary fat sources (fish oil, sunflower oil, poultry oil and fat powder, each with different fatty acid profiles) and three levels of MTM (0.0, 15 and 30 g/kg) offered through 10 days of adaptation and 70 days of main recording. Results showed that dietary inclusion of polyunsaturated fatty acids, including fish or sunflower oils, reduced serum cholesterol content but increased blood malondialdehyde (MDA) concentration (p < 0.05). While fish oil improved the yolk colour index and Haugh unit (p < 0.05), it decreased yolk cholesterol concentration (p < 0.01). The highest hepatic glycogen content and tissue integrity as well as the lowest liver lipid percentage and MDA content were observed in birds fed diets supplemented with poultry oil. On the other hand, feeding 30 g/kg of MTM reduced not only hepatic lipid percentage but also aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities (p < 0.01), while it improved eggshell strength and thickness (p < 0.05). Supplementation of fat powder enhanced hepatic C16:0 content, while addition of poultry, sunflower or fish oil increased C18:1, C18:2 or C20:5 concentrations respectively (p < 0.01); nonetheless, feeding the highest level of MTM reduced hepatic ΣSFA but increased Σn-3 fatty acids (p < 0.01). The interaction effects indicated that fish or sunflower oil supplementation increased the MTM level required to reduce not only serum or egg cholesterol concentrations (p < 0.05) but also blood or hepatic MDA content (p < 0.01). It was concluded that fish oil and MTM (30 g/kg) supplements might improve internal egg quality traits and eggshell quality respectively. The hepatic fatty acid profile was also found strongly correlated with dietary fatty acids. Finally, the best hepatic health indices and the highest oxidative stability were achieved when the birds were fed diets supplemented with poultry oil and 30 g/kg of MTM.

Prediction of mechanical extraction oil yield of new sunflower hybrids: artificial neural network model.

BACKGROUND: Sunflower seeds are in the top five most abundant oilseeds in the world, as well as sunflower oil in the edible oils group. Recently, increasing attention has been paid to cold-pressed sunflower oil because less processing is involved and no solvent is used. The present study was carried out to investigate dimensions (length, width, thickness), firmness, general (moisture content and hull content, mass of 1000 seeds), gravimetric (true and bulk density, porosity) and geometric characteristics (equivalent diameter, surface area, seed volume, sphericity) of 20 new sunflower hybrid seeds. Steps to determine most of these parameters are quite simple and easy since the process does not require long time or special equipment. RESULTS: Principal component analysis and cluster analysis confirmed differences in the mentioned characteristics between oily and confectionary sunflower hybrid seeds. One of the major differences between two groups of samples was in extraction oil yield. Mechanical extraction oil yield of the oily hybrid seeds was significantly (P Ë‚ 0.05) higher (from 68.72 ± 4.21% to 75.61 ± 1.99%) compared to confectionary hybrids (from 20.10 ± 2.82% to 39.91 ± 6.23%). Extraction oil yield values are known only after oil extraction. CONCLUSION: Knowledge of the extraction oil yield value before the mechanical extraction enables better management of the process. By application of the artificial neural network approach, an optimal neural network model was developed. The developed model showed a good generalization capability to predict the mechanical extraction oil yield of new sunflower hybrids based on the experimental data, which was a main goal of this paper. © 2021 Society of Chemical Industry.

Quantitative analysis of blended oils by matrix-assisted laser desorption/ionization mass spectrometry and partial least squares regression.

Quantitative labeling of oil compositions has become a trend to ensure the quality and safety of blended oils in the market. However, methods for rapid and reliable quantitation of blended oils are still not available. In this study, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was used to profile triacylglycerols in blended oils, and partial least squares regression (PLS-R) was applied to establish quantitative models based on the acquired MALDI-MS spectra. We demonstrated that this new method allowed simultaneous quantitation of multiple compositions, and provided good quantitative results of binary, ternary and quaternary blended oils, enabling good limits of detection (e.g., detectability of 1.5% olive oil in sunflower seed oil). Compared with the conventional GC-FID method, this new method could allow direct analysis of blended oils, analysis of one blended oil sample within minutes, and accurate quantitation of low-abundance oil compositions and blended oils with similar fatty acid contents.

Rapid screening for hazelnut oil and high-oleic sunflower oil in extra virgin olive oil using low-field nuclear magnetic resonance relaxometry and machine learning.

BACKGROUND: As extra virgin olive oil (EVOO) has high commercial value, it is routinely adulterated with other oils. The present study investigated the feasibility of rapidly identifying adulterated EVOO using low-field nuclear magnetic resonance (LF-NMR) relaxometry and machine learning approaches (decision tree, K-nearest neighbor, linear discriminant analysis, support vector machines and convolutional neural network (CNN)). RESULTS: LF-NMR spectroscopy effectively distinguished pure EVOO from that which was adulterated with hazelnut oil (HO) and high-oleic sunflower oil (HOSO). The applied CNN algorithm had an accuracy of 89.29%, a precision of 81.25% and a recall of 81.25%, and enabled the rapid (2 min) discrimination of pure EVOO that was adulterated with HO and HOSO in the volumetric ratio range of 10-100%. CONCLUSIONS: LF-NMR coupled with the CNN algorithm is a viable candidate for rapid EVOO authentication. © 2020 Society of Chemical Industry.

Olive oil mixtures. Part one: Decisional trees or how to verify the olive oil percentage in declared blends.

The commercialization of declared blends of olive oil and seed oil is something long approved by the European Union. There, the olive oil percentage must be at least 50% if the producer aims to advertise its presence on the front label, i.e., somewhere other than in the ingredients list. However, the Regulation did not propose any method to verify such proportion. For this purpose, we recommend the use of decisional trees, being the parameters under study those in which the greatest differences between olive and seed oils are shown: triacylglycerols, acyclic saturated hydrocarbons, free sterols, and tocopherols. In this way, to guarantee the presence of olive oil at 50%: i) palmitodiolein must be above 11-15%; ii) the ß/γ-tocopherol ratio must be below 2.4; iii) the alkane sum C21-C25 should be higher than 3.5-6%; and iv) the total sterol content cannot surpass 2400 mg/kg.

Random forest as one-class classifier and infrared spectroscopy for food adulteration detection.

This paper proposes the use of random forest for adulteration detection purposes, combining the random forest algorithm with the artificial generation of outliers from the authentic samples. This proposal was applied in two food adulteration studies: evening primrose oils using ATR-FTIR spectroscopy and ground nutmeg using NIR diffuse reflectance spectroscopy. The primrose oil was adulterated with soybean, corn and sunflower oils, and the model was validated using these adulterated oils and other different oils, such as rosehip and andiroba, in pure and adulterated forms. The ground nutmeg was adulterated with cumin, commercial monosodium glutamate, soil, roasted coffee husks and wood sawdust. For the primrose oil, the proposed method presented superior performance than PLS-DA and similar performance to SIMCA and for the ground nutmeg, the random forest was superior to PLS-DA and SIMCA. Also, in both applications using the random forest, no sample was excluded from the external validation set.

Role of supplemental UV-B in changing the level of ozone toxicity in two cultivars of sunflower: growth, seed yield and oil quality.

Ultraviolet-B radiation (UV-B) is inherent part of solar spectrum and tropospheric ozone (O3) is a potent secondary air pollutant. Therefore the present study was conducted to evaluate the responses of Helianthus annuus L. cvs DRSF 108 and Sungold (sunflower) to supplemental UV-B (sUV-B; ambient + 7.2 kJ m-2 d-1) and elevated ozone (O3; ambient + 10 ppb), given singly and in combination under field conditions using open-top chambers. The individual and interactive effects of O3 and sUV-B induced varying changes in both the cultivars of sunflower ranging from ultrastructural variations to growth, biomass, yield and oil composition. Reduction in leaf area of Sungold acted as a protective feature which minimized the perception of sUV-B as well as uptake of O3 thus led to lesser carbon loss compared to DRSF 108. Number- and weight of heads plant-1 decreased although more in Sungold with decline of oil content. Both the stresses when given singly and combination induced rancidification of oil and thus made the oil less suitable for human consumption.

A cotton thread fluidic device with a wall-jet pencil-drawn paper based dual electrode detector.

A simple and sensitive device is presented based on the use of pencil-drawn paper based electrochemical detector placed at the end of a cotton thread fluidic channel in wall-jet configuration. This innovative and fast responding electroanalytical system can be adopted for both single and dual electrode electrochemical detection, this last achieved by applying two different potentials at two independent working electrodes drawn on the opposite faces of the paper based detector. Its performance was preliminarily optimized by adopting hexacyanoferrate(II) as probe species undergoing reversible electrochemical processes. These devices were then used for the single electrode detection of ascorbic acid in aqueous samples and the dual electrode detection of orthodiphenols in extra virgin olive oils (EVOOs). In fact, these devices enable hydrophilic orthodiphenols, typically present in EVOOs (extracted by a 80:20% v/v acetonitrile/water mixture), to be discriminated from hydrophilic monophenols instead present in almost all vegetable oils. Flow-injections runs were conducted by using a 0.01 M H2SO4 + 0.5 KCl running electrolyte allowing the rapid and selective detection of hydrophilic orthodiphenols with satisfactory sensitivity and a low enough detection limit (2 µM). Different real samples of EVOOs and sunflower oils were analyzed. Abundant enough contents of orthidiphenols were found in EVOO samples, while no trace of these antioxidants was found in sunflower oils.

A novel method for detection of camellia oil adulteration based on time-resolved emission fluorescence.

In this study, time-resolved emission fluorescence (TRES) combined with chemometrics was developed and employed for adulteration analysis of camellia oil. TRES was first decomposed by parallel factors analysis (PARAFAC). Next, an artificial neural network (ANN) model was built for the adulteration analysis. A linear range of 5-50%, a limit of detection (LOD) of 3% and root mean square error of prediction (RMSEP) values lower than 3% were achieved. Compared with the steady-state measurement, easy access to the information from fluorophores of low concentration was shown to be an intrinsic advantage of the time-resolved measurement; this advantageous characteristic was helpful for optimizing adulteration analysis. It was demonstrated that TRES combined with chemometrics was a simple, rapid and non-intrusive method for adulteration analysis of vegetable oil.

The effects of Plantago major seed gum on steady and dynamic oscillatory shear rheology of sunflower oil-in-water emulsions.

The effects of Plantago major seed (PMS) gum on the rheological properties of the sunflower oil-based emulsions (steady shear flow and dynamic oscillatory rheology) were investigated. The results of steady shear flow experiments showed that the shear stress-shear rate, apparent viscosity-shear rate, and shear stress-time data were well fitted with Herschel-Bulkley, Carreau, and Tiu-Bogar models, respectively, and showed the highest R2 and the lower root mean square error within different models. The strain and frequency sweep data indicated that all emulsions showed weak gel-like behavior, which showed stable interactions and entanglements in the emulsion structure. CoX-Merz rule was applied to investigate the relationship between complex viscosity (η*) and apparent viscosity (ηa ). In all emulsions containing PMS gum, η* > η a and they did not obey from this rule. PRACTICAL APPLICATIONS: The rheological properties of emulsion are critical features in stabilization of emulsion based products. The PMS gum can potentially be used in producing and stabilization of emulsion based products and effects of this gum on in oil in water emulsion can be useful in development of plant originated hydrocolloids in foods.

The role of edible oils in low molecular weight organogels rheology and structure.

In this paper, the role of solvent characteristics on the rheological and physicochemical properties of organogels was investigated using different techniques. Vegetable oils, such as rice, sunflower and castor oil were used as solvents, for producing organogels with monoglycerides of fatty acids or a mixture of fatty alcohols (policosanol) as gelators. Moreover, two non-edible oils (silicon and paraffin oil) were also used for analysing the properties of solvents completely different in nature with respect to the edible ones, for a better interpretation of the given results. Organogels were investigated from a rheological point of view and through a microscopic analysis, given by polarised light (POM) and atomic force (AFM) microscopy, and X-rays to study the crystallinity of the system. The IR technique was used to analyse the intermolecular interactions, resulting in interesting information about the effect of oil polarity on the driving forces promoting structuration. This investigation showed that when solvents of a similar chemical nature are used, their physical properties, mainly oil polarity, are strictly related to the properties of the organogel, such as the onset of crystallisation temperature, the stiffness of the final material and its crystallinity. Anyway, these physical parameters seem insufficient to describe properly the role of solvents when oils of a different chemical nature are compared.

Sunflower Oil and Nannochloropsis oculata Microalgae as Sources of Unsaturated Fatty Acids for Mitigation of Methane Production and Enhancing Diets' Nutritive Value.

The objective of this assay was to investigate the effect of adding sunflower oil, Nannochloropsis oculata microalgae and their mixture at 0, 1, 2, 3, 4, and 5% to three total mixed rations (TMRs) with different concentrate:forage ratios (40C:60F, 50C:50F, and 60C:40F) on in vitro gas production (GP), methane (CH4) production, and nutrient degradability. Asymptotic GP, GP rate, CH4 concentration/g acid detergent fiber (ADF), dry matter (DM) degradability (DMD), short chain fatty acids (SCFAs), and ruminal bacteria population increased, but neutral detergent fiber (NDF) degradability (NDFD), ADF degradability (ADFD), and protozoa count decreased with increasing concentrate level in the TMR. Methane production/g DM and NDF was higher for 50C:50F TMR. Sunflower oil reduced asymptotic GP, lag time, CH4 production/g ADF, ammonia-N (NH3-N), and SCFA. Compared to the control treatments, additives decreased GP rate, while sunflower oil/N. oculata mixture increased DMD and NDFD. All additives at 5% increased GP rate and lag time and decreased CH4 production/g DM, ADF, and NDF, ruminal NH3-N, and protozoa count. All additives at 2% increased DMD, NDFD and ADFD, SCFA, and bacteria population. Supplementation of TMR, containing different concentrate:forage ratios, with sunflower oil, N. oculata, and sunflower oil/N. oculata mixture at different doses modified in vitro GP, CH4 production, and nutrient degradability.

High-throughput authentication of edible oils with benchtop Ultrafast 2D NMR.

We report the use of an Ultrafast 2D NMR approach applied on a benchtop NMR system (43 MHz) for the authentication of edible oils. Our results demonstrate that a profiling strategy based on fast 2D NMR spectra recorded in 2.4 min is more efficient than the standard 1D experiments to classify oils from different botanical origins, since 1D spectra on the same samples suffer from strong peak overlaps. Six edible oils with different botanical origins (olive, hazelnut, sesame, rapeseed, corn and sunflower) have been clearly discriminated by PCA analysis. Furthermore, we show how this approach combined with a PLS model can detect adulteration processes such as the addition of hazelnut oil into olive oil, a common fraud in food industry.

Comparison of the effects of flaxseed oil and sunflower seed oil consumption on serum glucose, lipid profile, blood pressure, and lipid peroxidation in patients with metabolic syndrome.

BACKGROUND: Metabolic syndrome (MetSyn) increases the risk of type II diabetes and morbidity and mortality due to cardiovascular diseases. Flaxseed oil (FO), as a functional food, is one of the major vegetal sources of essential omega-3 fatty acids. OBJECTIVE: This study aimed to compare the effects of consumption of FO and sunflower seed oil (SO) on lipid peroxidation and other symptoms of MetSyn. METHODS: This randomized controlled interventional trial was conducted on 60 volunteers aged 30 to 60 years who were diagnosed with MetSyn in Shiraz, Iran. The participants who fulfilled the inclusion criteria were randomly assigned to SO (n = 30, receiving 25 mL/d SO) and FO (n = 30, receiving 25 ml/d FO) groups using block randomization. The diets were identical for all the participants. Blood pressure (BP), serum lipid, fasting blood sugar, and malondialdehyde were measured at baseline and at the end of week 7. RESULT: The results showed no significant difference between the 2 groups regarding blood lipid levels and fasting blood sugar at the end of the study. However, significant reductions in total cholesterol, low-density lipoprotein cholesterol (5.6% in FO and 10.8% in SO), and triglyceride levels were seen within each group after treatment with FO and SO (P < .05). Nonetheless, between-group changes were significant (<0.05) for systolic BP (mean [±standard deviation {SD}] changes were -14.0 ± 22.41 in the FO group [P = .004] and 0.92 ± 8.70 in the SO group [P = .594]) and diastolic BP (mean [±SD] changes were -4.26 ± 7.44 in the FO group [P = .007] and 1.30 ± 6.91 in the SO group [P = .344]), but marginally significant (P = .053) for malondialdehyde level (mean [±SD] changes were -1.29 ± 1.48 in the FO group [P < .001] and -0.52 ± 1.34 in the SO group [P = .52]). A significant decrease in weight was also found in both groups. However, waist circumference decreased significantly only in the FO group at the end of the study (P < .05). CONCLUSION: Our results indicated that dietary FO could be effective in amelioration of some symptoms of MetSyn and decrease BP and lipid peroxidation.

Influence of High Temperature and Duration of Heating on the Sunflower Seed Oil Properties for Food Use and Bio-diesel Production.

Two important problems for the food industry are oil oxidation and oil waste after frying. Sunflower seed oil is one of the vegetable oils most commonly used in the food industry. Two variables were applied to the low oleic sunflower seed oil in this work i.e. heating temperature (180-210-240°C) and time of heating (15-30-60-120 minutes), to study from the edible point of view the variations of its physico-chemical properties. After 120 minutes heating at 240°C the following was found: refractive index (1.476), free acidity (0.35%), K232 (2.87), K270 (3.71), antiradical activity (45.90% inhibition), total phenols (523 mg kg-1), peroxide value (17.00 meq kg-1), p-anisidine value (256.8) and Totox (271.7), all of which showed a constant deterioration. In relation to the use as a feedstock for bio-diesel production, after 120 minutes heating at 240℃ the following was found: acid value 0.70 mg KOH g-1 oil, iodine value 117.83 g I2 100 g-1 oil, oil stability index 0.67 h, kinematic viscosity (at 40°C) 77.85 mm2 s-1, higher heating value 39.86 MJ kg-1, density 933.34 kg/m3 and cetane number 67.04. The parameters studied in this work were influenced, in different ways, by the applied variables. Heating temperature between 180 and 210°C and 120 min heating duration were found to be the most appropriate conditions for sunflower seed oil both from the deep frying point of view and from a subsequent use as feedstock for bio-diesel production. In light of the vegetable oils' International standards for an edible use and for a bio-diesel production, findings of this work can be used to set heating temperature and heating duration to preserve as long possible the physico-chemical properties of a low oleic sunflower seed oil for both its edible use as a fat during cooking and for its re-use after frying.

Spectral analysis of the stick-slip phenomenon in "oral" tribological texture evaluation.

"Oral" tribology has become a new paradigm in food texture studies to understand complex texture attributes, such as creaminess, oiliness, and astringency, which could not be successfully characterized by traditional texture analysis nor by rheology. Stick-slip effects resulting from intermittent sliding motion during kinetic friction of oral mucosa could constitute an additional determining factor of sensory perception where traditional friction coefficient values and their Stribeck regimes fail in predicting different lubricant (food bolus and saliva) behaviors. It was hypothesized that the observed jagged behavior of most sliding force curves are due to stick-slip effects and depend on test velocity, normal load, surface roughness as well as lubricant type. Therefore, different measurement set-ups were investigated: sliding velocities from 0.01 to 40 mm/s, loads of 0.5 and 2.5 N as well as a smooth and a textured silicone contact surface. Moreover, dry contact measurements were compared to model food systems, such as water, oil, and oil-in-water emulsions. Spectral analysis permitted to extract the distribution of stick-slip magnitudes for specific wave numbers, characterizing the occurrence of jagged force peaks per unit sliding distance, similar to frequencies per unit time. The spectral features were affected by all the above mentioned tested factors. Stick-slip created vibration frequencies in the range of those detected by oral mechanoreceptors (0.3-400 Hz). The study thus provides a new insight into the use of tribology in food psychophysics. PRACTICAL APPLICATIONS: Dynamic spectral analysis has been applied for the first time to the force-displacement curves in "oral" tribology. Analyzing the stick-slip phenomenon in the dynamic friction provides new information that is generally overlooked or confused with machine noise and which may help to understand friction-related sensory attributes. This approach allows us to differentiate samples that have similar friction coefficient, but are perceived differently in the mouth. The next step of our research will be to combine spectral attributes, such as the magnitudes of specific wave number bands and possibly their evolution during sliding, together with friction coefficient and viscosity values of foods with sensory results. The highest potential lies in predicting smoothness in opposition to roughness of a surface, such as a rough tongue when eating astringent or dry foods, or of particles when eating grainy foods. The effects of food ingredients at the nano to macroscales can then be used to optimize a specific lubrication behavior.

Synchronous fluorescence spectroscopy for determination of tahini adulteration.

In this study, a quick and simple method was developed for detection of tahini adulteration with sunflower oil. The synchronous fluorescence spectroscopy (SFS) data of oil samples were collected by scanning the excitation and emission monochromators simultaneously with 20, 40, 60 and 80nm wavelength intervals within the range of 250-600nm. Three different multivariate calibration methods, namely partial least squares (PLS) analysis, principal component regression (PCR), and multiple linear regression (MLR) were used for data analysis. Wavelength selection feature of the chemometric software was also used in order to determine the optimum range of each dataset collected at 20, 40, 60 and 80nm wavelength intervals. All regression methods with and without wavelength selection mode were applied to these each dataset individually. Application of wavelength selection mode adversely affected the root mean square error of cross validation (RMSECV) and root mean square error of prediction (RMSEP) values and other quality parameters of all calibration and validation models which were built by using each dataset collected at 20, 40, 60 and 80nm wavelength intervals. Taking all parameters into consideration, the best results were obtained through the application of PLS analysis without wavelength selection mode on the SFS data collected at all wavelength intervals. The lowest detection limits of adulteration, 0.09% and 0.15% were obtained through the use of 40 and 80nm as wavelength intervals, respectively. RMSECV and RMSEP values were calculated as 0.74 and 1.26 for 40nm, and 0.65 and 0.81 for 80nm wavelength intervals.

Frying oils with high natural or added antioxidants content, which protect against postprandial oxidative stress, also protect against DNA oxidation damage.

PURPOSE: Using sunflower oil as frying oil increases postprandial oxidative stress, which is considered the main endogenous source of DNA oxidative damage. We aimed to test whether the protective effect of virgin olive oil and oil models with added antioxidants against postprandial oxidative stress may also protect against DNA oxidative damage. METHODS: Twenty obese people received four breakfasts following a randomized crossover design consisting of different oils [virgin olive oil (VOO), sunflower oil (SFO), and a mixed seed oil (SFO/canola oil) with added dimethylpolysiloxane (SOX) or natural antioxidants from olives (SOP)], which were subjected to 20 heating cycles. RESULTS: We observed the postprandial increase in the mRNA levels of p53, OGG1, POLB, and GADD45b after the intake of the breakfast prepared with SFO and SOX, and an increase in the expression of MDM2, APEX1, and XPC after the intake of the breakfast prepared with SFO, whereas no significant changes at the postprandial state were observed after the intake of the other breakfasts (all p values <0.05). We observed lower 8-OHdG postprandial levels after the intake of the breakfast prepared with VOO and SOP than after the intake of the breakfast prepared with SFO and SOX (all p values <0.05). CONCLUSIONS: Our results support the beneficial effect on DNA oxidation damage of virgin olive oil and the oil models with added antioxidants, as compared to the detrimental use of sunflower oil, which induces p53-dependent DNA repair pathway activation.