Extra Virgin Olive Research Articles

Assembly and characterization of an optical fiber probe for use in a portable Raman spectrometer

This study describes the assembly and testing of an optical fiber Raman probe for use in a portable spectrometer using a 785 nm laser. The Raman probe was tested on edible vegetable oils (extra virgin olive, canola, sunflower, corn, and soybean), with the distal end of the probe immersed in each sample. The spectra of a dipyrone tablet and a mothball were also obtained. The silica peaks were subtracted by taking a spectrum with the probe tip immersed in water. The spectra of the samples exhibited characteristic peaks from vibrations of unsaturated fatty acids between 900 and 1800 cm−1, as well as characteristic peaks of silica from 600 to 1200 cm−1. The spectra of the samples after subtraction of the silica spectrum (probe in water) showed characteristic peaks without alterations in position or relative intensities compared without the probe. Exploratory analysis by principal component analysis was able to identify peaks of the constituent fatty acids in the oils and associate them with the oil type. A classification model based on partial least squares regression allowed for the classification of oil spectra with an accuracy of 77%. This study demonstrated the feasibility of coupling a probe to a portable Raman spectrometer with the goal of monitoring and controlling industrial processes.

Comparative study of virgin olive oil from Moroccan Picholine cultivars in TADLA perimeter -Morocco

Olive oil, extracted from olive fruits (Olea europaea), is renowned for its distinctive flavour, nutritional richness and health benefits. The aim of this comparative study is to analyze olive oil from several TADLA perimeter units, including Province of AZILAL, FQUIH BEN SALAH, BENI MELLAL, ZAOUIT CHEIKH, and BRADIA. The oil under investigation was extracted from olives of the Moroccan Picholine variety, by a discontinuous system including grinding, pressing and decanting. Significant variations were found at the values of the studied parameters. The results of our study showed that Olive oil from FBS and BM are classified as an extra virgin olive. However, olive oils from ZC, BR and AZ are classified as virgin olive oil. Sample from FQUIH BEN SALAH province had the lowest Free Fatty Acids (FFA) and peroxide values 0.236% oleic acid and 3.434 méqO2/Kg respectively. While the highest FFA value found was the olive oil obtained from AZILAL (1.084% Oléic Acid) and the highest Peroxide value was obtained in the sample from BRADIA (8.108 méq O2/Kg). E232, E270 and delta K values of all samples were under the limit fixed by IOC for virgin olive oil. Polyphenols content of ZAOUIT CHEIKH, FQUIH BEN SALAH and BRADIA oils are relatively high with values equal to 1.347, 1.082, and 1.141mg GA/100ml extract respectively. DPPH test showed that ZAOUIT CHEIKH oil had the greater antioxidant capacity.

Yearly attained adherence to Mediterranean diet and incidence of diabetes in a large randomized trial

BackgroundSeveral large observational prospective studies have reported a protection by the traditional Mediterranean diet against type 2 diabetes, but none of them used yearly repeated measures of dietary intake. Repeated measurements of dietary intake are able to improve subject classification and to increase the quality of the assessed relationships in nutritional epidemiology. Beyond observational studies, randomized trials provide stronger causal evidence. In the context of a randomized trial of primary cardiovascular prevention, we assessed type 2 diabetes incidence according to yearly repeated measures of compliance with a nutritional intervention based on the traditional Mediterranean diet.MethodsPREDIMED (‘‘PREvención con DIeta MEDiterránea’’) was a Spanish trial including 7447 men and women at high cardiovascular risk. We assessed 3541 participants initially free of diabetes and originally randomized to 1 of 3 diets: low-fat diet (n = 1147, control group), Mediterranean diet supplemented with extra virgin olive (n = 1154) or Mediterranean diet supplemented with mixed nuts (n = 1240). As exposure we used actual adherence to Mediterranean diet (cumulative average), yearly assessed with the Mediterranean Diet Adherence Screener (scoring 0 to 14 points), and repeated up to 8 times (baseline and 7 consecutive follow-up years). This score was categorized into four groups: < 8, 8–< 10, 10– < 12, and 12–14 points. The outcome was new-onset type 2 diabetes.ResultsMultivariable-adjusted hazard ratios from time-varying Cox models were 0.80 (95% confidence interval, 0.70–0.92) per + 2 points in Mediterranean Diet Adherence Screener (linear trend p = .001), and 0.46 (0.25–0.83) for the highest (12–14 points) versus the lowest (< 8) adherence. This inverse association was maintained after additionally adjusting for the randomized arm. Age- and sex-adjusted analysis of a validated plasma metabolomic signature of the Mediterranean Diet Adherence Screener (constituted of 67 metabolites) in a subset of 889 participants also supported these results.ConclusionsDietary intervention trials should quantify actual dietary adherence throughout the trial period to enhance the benefits and to assist results interpretation. A rapid dietary assessment tool, yearly repeated as a screener, was able to capture a strong inverse linear relationship between Mediterranean diet and type 2 diabetes.Trial registration ISRCTN35739639

Oil Pulling and Polyphenols: Treatment of Gingivitis Patients with 'Itri Extra-Virgin Olive Oil'.

The aim of the study was to evaluate the effectiveness of extra virgin olive (EVO) oil and fruity oil for the treatment of gingivitis. A sample of 75 patients over 18 years of age with gingivitis induced by plaque bacteria was divided into three groups: study group A, with extra virgin olive oil; study group B, with fruity oil; and control group C. In the two study groups, EVO oil was administered as a mouthwash to patients with gingival inflammation. The protocol included a daily application of the product for 30 days, with three recalls 15 days apart. Clinical parameters of plaque formation and gingivitis, including plaque index (PI) and bleeding index (BI), were assessed at each recall and scored on a specific periodontal chart. The control group received no mouthwash treatment in addition to normal daily oral hygiene procedures, and the same clinical parameters as the study group were evaluated. Data were evaluated using SPSS 27.0 software for Windows (SPSS Inc., Chicago, IL, USA). Then, the pre- and post-treatment values of the groups were compared using Student's t-test, setting p < 0.05 as the significance level. Comparison of the three groups showed that extra-virgin olive oil was an adjuvant in the treatment of gingival inflammation, improving PI and BI. In group A, the mean plaque index showed a 48% reduction, and the bleeding index showed a 64% reduction after 30 days. In group B, the mean plaque index showed a 35% reduction and a bleeding index reduction of 43% after 30 days. The collected data showed significant improvements in the formation of bacterial plaque and gingivitis. The exact mechanism of such treatment is still to be elucidated. As a result of this, further studies with a different sample of patients than those used and a comparison with other products need to be addressed to verify and demonstrate the antibacterial and anti-inflammatory effects of the components of this natural product.

Anti-Arthritic and Anti-Cancer Activities of Polyphenols: A Review of the Most Recent In Vitro Assays

Polyphenols have gained widespread attention as they are effective in the prevention and management of various diseases, including cancer diseases (CD) and rheumatoid arthritis (RA). They are natural organic substances present in fruits, vegetables, and spices. Polyphenols interact with various kinds of receptors and membranes. They modulate different signal cascades and interact with the enzymes responsible for CD and RA. These interactions involve cellular machinery, from cell membranes to major nuclear components, and provide information on their beneficial effects on health. These actions provide evidence for their pharmaceutical exploitation in the treatment of CD and RA. In this review, we discuss different pathways, modulated by polyphenols, which are involved in CD and RA. A search of the most recent relevant publications was carried out with the following criteria: publication date, 2012-2022; language, English; study design, in vitro; and the investigation of polyphenols present in extra virgin olive, grapes, and spices in the context of RA and CD, including, when available, the underlying molecular mechanisms. This review is valuable for clarifying the mechanisms of polyphenols targeting the pathways of senescence and leading to the development of CD and RA treatments. Herein, we focus on research reports that emphasize antioxidant properties.

An Oleocanthal-Enriched EVO Oil Extract Induces the ROS Production in Gastric Cancer Cells and Potentiates the Effect of Chemotherapy.

Oleocanthal, a minor polar compound in extra-virgin olive (EVO) oil, contains anticancer properties, which should be encouraged in its use in oncology. Gastric Cancer (GC), a very aggressive human cancer, is often diagnosed at advanced stages, when surgery is substituted or supported by chemotherapy (CT). However, CT frequently fails due to the patient’s resistance to the treatment. Thus, the aim of this study is to verify whether an OC-enriched EVO oil extract fraction (OCF) may be useful in order to overcome a resistance to GC. We evaluated the OCF effects on an AGS gastric adenocarcinoma cell line wild type (AGS wt) and on its subpopulations resistant to 5-fluorouracil (5FUr), Paclitaxel (TAXr) or cisplatin (CISr). We found that a 60 µM dose of the OCF acts on the AGS wt, 5FUr and TAXr, leading to the cell cycle inhibition and to a ROS production, but not on CISr cells. Resistance of CISr to the OCF seems to be due to higher levels of antioxidant-enzymes that can counteract the OCF-induced ROS production. Moreover, using the OCF plus 5-fluorouracil, Paclitaxel or cisplatin, we found a potentiating effect compared with a mono-treatment in all resistant GC cells, including CISr. In conclusion, the use of the OCF in the management of GC has shown very interesting advantages, opening-up the possibility to evaluate the efficacy of the OCF in vivo, as a valid adjuvant in the treatment of resistant GC.

Nuclear Magnetic Resonance Spectroscopic Analysis of the Evolution of Peroxidation Products Arising from Culinary Oils Exposed to Thermal Oxidation: An Investigation Employing 1H and 1H-1H COSY and TOCSY Techniques.

Scientific warnings on the deleterious health effects exerted by dietary lipid oxidation products (LOPs) present in thermally stressed culinary oils have, to date, not received adequate attention given that there has been an increase in the use and consumption of such oil products in everyday life. In this study, high-resolution 1H nuclear magnetic resonance (NMR) analysis was used to characterize and map chemical modifications to fatty acid (FA) acyl groups and the evolution of LOPs in saturated fatty acid (SFA)-rich ghee, monounsaturated fatty acid (MUFA)-rich groundnut, extra virgin olive, and macadamia oils, along with polyunsaturated fatty acid (PUFA)-rich sesame, corn and walnut oils, which were all thermally stressed at 180 °C, continuously and discontinuously for 300 and 480 min, respectively. Results acquired revealed that PUFA-rich culinary oils were more susceptible to thermo-oxidative stress than the others tested, as expected. However, ghee and macadamia oil both generated only low levels of toxic LOPs, and these results demonstrated a striking similarity. Furthermore, at the 120 min thermo-oxidation time-point, the discontinuous thermo-oxidation episodes produced higher concentrations of aldehydic LOPs than those produced during continuous thermo-oxidation sessions for the same duration. On completion of the thermo-oxidation period, a higher level of triacylglycerol chain degradation, and hence, higher concentrations of aldehydes, were registered in culinary oils thermally stressed continuously over those found in discontinuous thermo-oxidized oils. These findings may be crucial in setting targets and developing scientific methods for the suppression of LOPs in thermo-oxidized oils.

Physicochemical properties and microstructure of composite surimi gels: The effects of ultrasonic treatment and olive oil concentration

This study was conducted to evaluate the effects of extra virgin olive (EVO) oil incorporation on the physicochemical properties and microstructure of surimi gels subjected to ultrasound-assisted water-bath heating. As the oil content was increased from 0 to 5 g/100 g, the breaking force and gel strength of the surimi gels significantly decreased, while the whiteness level exhibited the opposite tendency irrespective of the heating method. Compared with the traditional water-bath heating method, the ultrasonic heating promoted the unfolding of the α-helix structure and intensified the formation of β-sheet content and non-covalent bonds (ionic bonds, hydrogen bonds, and disulfide bonds), especially disulfide bonds, which contributed to the further crosslinking of the proteins and to gelation, thereby improving the gels’ strength. In addition, smaller cavities and compact microstructures were observed in the low-oil (≤3 g/100 g) surimi gels under ultrasonic treatment, which effectively prevented water migration in the gel network and resulted in a high water holding capacity and uniform water distribution. However, the ultrasonic treatment barely remedied the poor microstructures of the high-oil (>3 g/100 g) surimi gels owing to oil coalescence, which weakened the protein–protein interaction. In conclusion, ultrasonic treatment combined with water-bath heating significantly improved the gelation properties of the low-oil surimi gels, although it did not remarkably improve those of the high-oil gels. The choice of a suitable oil concentration could be of great importance for the production and functioning of surimi products via ultrasound-assisted treatments.

Front Face Fluorescence Spectroscopy Combined with PLS‐DA Allows to Monitor Chemical Changes of Edible Vegetable Oils during Storage at 60 °C

AbstractIn this work, front‐face fluorescence spectroscopy coupled with chemometric tools are used for the monitoring of rapeseed, sunflower, extra virgin olive, and linseed oil. The oil samples are heated at 60 °C for up to 15 days. The fluorescence excitation spectra are scanned in the range of 270–420 nm and 250–310 nm after emission wavelength set at 450 and 330 nm, respectively. The primary and secondary lipid oxidation products are also determined on the same oil samples. By applying partial least square discriminant analysis (PLS‐DA) to each spectral collection obtained after emission set at 450 and 330 nm, clear discrimination of edible oil samples according to their botanical types, and sometimes aging, is obtained.Practical Applications: This study shows that oxidation of rapeseed, sunflower, extra virgin olive, and linseed oil monitored different trends due to their difference in composition. The presented results demonstrated the capability of the front‐face fluorescence spectroscopy to differentiate four vegetable oils contained in capped and uncapped flasks indicating the evolution of primary and secondary indicators of oxidation during the storage period. The technology can be exploited at the industrial level for monitoring in a non‐destructive manner the level of oxidation of edible oil.

Use of Raman Spectroscopy for Analysis and Detection of Some Sudanese Edible Oils

Vegetable edible oils provide high nutritional and health value in the Sudanese diet. It is also used in the pharmaceutical industry and an essential ingredient in cosmetics. This paper reviews the use of Raman spectroscopy for the analysis, quality and characterization of edible oils, including six types of oils (corn, extra virgin olive, sunflower, factory sesame, presses sesame, and peanut) purchased from local Sudanese stores. The results showed that the spectra of edible oils are similar, but they show some differences that, despite their smallness, allow them to be distinguished from each other. Divide the spectrum into the fingerprint region. The range ranges between (600 and 1800) cm^-1 the silent region", this spectral region is (1800 to 2500) cm^-1, and range is from (2500 to 3400) cm^-1, known as the "high wave number region". Raman spectra also pliable the determination of the degree of saturation and unsaturation of oils. This characteristic is related to the value of iodine, and the degree of unsaturation can be used to classify and approve oils, which is especially useful with high-quality oils in the appearance of the vibration modes at 1155 cm^-1 and 1525 cm^-1. Adulteration of edible oils with cheaper oils is a major concern in the oil industry. The capabilities of a Raman spectrometer were checked to assess the purity of the samples (peanut spectrum and presses sesame spectrum). Raman spectroscopy allowed the examination of secondary components such as sterols, hydrocarbons, terpene alcohols and polyphenols. Raman spectroscopy is used because this innovative method provides fast, non-destructive and reagent-free measurements, samples do not need to be processed and do not require large volumes.

Vegetable oils protect phycocyanin from thermal degradation during cooking of spirulina-based “crostini”

Phycocyanin is a well-known bioactive pigment contained in cyanobacteria, such as Arthrospira platensis (commonly known as spirulina), and used in the food and beverage industry. One of the main problems that affects spirulina-based bakery products is phycocyanin degradation during cooking, being this pigment extremely sensitive to heat.The main goal of this work was to evaluate the protective effect against phycocyanin degradation of extra virgin olive (EVO) oil or sunflower oil, by applying thermal treatments directly on A. platensis F&M-C256 biomass and on A. platensis F&M-C256-based “crostini”, as well as on phycocyanin powder. After cooking, A. platensis F&M-C256 “crostini” incorporated with EVO or sunflower oil (10g oil/100g of dough) maintained about 90% of the phycocyanin originally present in the cyanobacterial biomass. When pure tocopherol was added to the biomass in the same amounts, a significant protective effect against phycocyanin degradation was observed. Tocopherol contained in EVO and sunflower oils is the putative main responsible for the protective action against phycocyanin degradation. Therefore, the incorporation of vegetable oils into the dough can be a useful tool for the food industries that use A. platensis biomass and/or phycocyanin as a natural food coloring and bioactive component for bakery products.

Effect of a Mediterranean Diet-Based Nutritional Intervention on the Risk of Developing Gestational Diabetes Mellitus and Other Maternal-Fetal Adverse Events in Hispanic Women Residents in Spain.

Gestational diabetes mellitus (GDM) is the most frequent morbidity found in pregnancy, and it increases the risk for several maternal-fetal complications. Hispanic women are considered at high risk. The St. Carlos GDM prevention study is a randomized controlled trial (RCT) conducted from 2016–2017. Normoglycemic women were randomized at 12–14 Gestation week (WG) to an intervention group (IG) receiving recommendations based on the MedDiet (supplemented with ExtraVirgin Olive Oil/pistachios), or to a control group (CG), recommended to limit fat intake. After RCT conclusion, IG recommendations were applied to a real-world group (RW) in routine clinical practice. The primary endpoint of the current study is an assessment of the GDM rate in Hispanic participants of the aforementioned studies: 132 RCT, 128 CT, 284 RW participants. The GDM rate was lower in IG: 19/128(14.8%), p = 0.021, and RW: 38/284(13.4%), p = 0.029) than in CG: 34/132(25.8%). Adjusted RR (95%CI) for GDM: 0.72 (0.50–0.97), p = 0.037 in IG and 0.77 (0.61–0.97), p = 0.008 in RW. Rates of urinary tract infections, emergency caesarean-sections and perineal trauma were also lower in IG and RW. Other adverse outcomes were lower in IG vs. CG. In conclusion, a MedDiet-based intervention reduces the rate of GDM and several adverse maternal-fetal outcomes in Hispanic women residing in Spain.

Modeling of phononic crystal cavity for sensing different biodiesel fuels with high sensitivity

The biodiesel production process requires accurate information about its physical properties for monitoring the production process. This work introduced a one-dimensional ternary phononic crystal (1D-TPnC) sensor capable of discriminating and sensing between the acoustic properties of different biodiesel fuels in the ultrasonic range. The sensor structure combines a liquid-filled defect layer into a perfect TPnC. The liquid-filled defect layer restores some of the incident acoustic energy and excites a transmitted resonant dip inside the reflection spectrum. The reflection spectrum of the layered TPnC structure is calculated based on the transfer matrix method (TMM). The simulations showed that the proposed sensor has the feature of being ultra-highly sensitive and selective between the Extra-virgin olive, Tesco sunflower, Methyl Oleate, and Soybean biofuels.The numerical results revealed that Soybean oil has the highest sensitivity (76589 m−1) and Q-factor (267) compared with the other three oils. For Methyl Oleate, the sensitivity and quality factor of the sensor reached the values of about 12680 m−1 and 204, respectively. With increasing the temperature from 30 ∘C to 50 ∘C, the sensitivity increased from 33853Hz/ °C to 36096 Hz/ ∘C for Soybean oil while it decreased from 4064 Hz/ ∘C to 37243 Hz/ ∘C for Methyl Oleate oil. This is because the Soybean oil has a higher speed of sound than Methyl Oleate. The proposed sensor has higher performance than many previously reported PnC sensors. Also, it can be used to determine different types of biodiesel fuels.

Characterization of Olive Oils Used as Medium in Canned Fish

Fish products are often sold together with vegetable oil such as olive oil. Lately, the market also offers fish products with extra virgin olive oil...

Structure, activity and dynamics of extra virgin olive oil-in-water nanoemulsions loaded with vitamin D3 and calcium citrate

Extra virgin olive oil-in-water (O/W) nanoemulsions loaded with vitamin D3 and calcium citrate were developed and studied in terms of structure, activity and dynamics. The nanoemulsions were formulated with a two-step emulsification procedure using water as the continuous phase, extra virgin olive oil (EVOO) as the dispersed phase and mixtures of food grade surfactants as stabilizers. The nanoemulsions were investigated for their particle size, polydispersity and stability over time by Dynamic light scattering (DLS) analysis. Among the different nanoemulsions studied, those based on polysorbate 20 in combination with lecithin produced systems owing EVOO droplets of 285 ± 5 nm diameter and 0.202 ± 0.01 PdI that were stable for 37 days. These stable nanoemulsions were loaded with calcium citrate and vitamin D3 to result formulations containing both water and oil soluble micronutrients. The presence of calcium ions in the aqueous phase strongly affected the stability of the nanoemulsions whereas vitamin D3 addition in the dispersed oil phase affected the size of the oil cores by several nanometers. Interfacial properties were investigated using Electron Paramagnetic Resonance (EPR) spectroscopy employing an amphiphilic spin probe. The nature of the surfactant and the presence of vitamin D3 and calcium citrate affected the properties of the surfactants' layer in terms of rigidity, local viscosity and polarity. More specifically, upon encapsulation vitamin D3 resulted in more ordered and viscous interfaces. Antioxidant potential of the proposed nanocarriers was investigated with an EPR procedure based on the scavenging the 4-hydroxy-TEMPOL. EPR signal inhibition was observed due to the scavenging activity of hydrogen donating moieties present both in empty and loaded nanoemulsions. Diffusion ordered NMR spectroscopy (DOSY NMR) successfully revealed the solubilization of the lipophilic vitamin D3 in the dispersed oil phase of the nanoemulsion formulation.

Extra Virgin Olive Oil and Nigella sativa Oil Produced in Central Italy: A Comparison of the Nutrigenomic Effects of Two Mediterranean Oils in a Low-Grade Inflammation Model.

Extra virgin olive (EVO) oil and Nigella sativa (NG) oil are two well-known Mediterranean foods whose consumption has been associated with beneficial effects on human health. This study investigates the nutrigenomic properties of two high quality EVO and NG oils in an in vitro model of low-grade inflammation of human macrophages (THP-1 cells). The aim was to assess whether these healthy foods could modulate inflammation through antioxidant and epigenetic mechanisms. When THP-1 cells were co-exposed to both lipopolysaccharides (LPS)-induced inflammation and oils, both EVO and NG oils displayed anti-inflammatory activity. Both oils were able to restore normal expression levels of DNMT3A and HDAC1 (but not DNMT3B), which were altered under inflammatory conditions. Moreover, EVO oil was able to prevent the increase in TET2 expression and reduce global DNA methylation that were measured in inflamed cells. Due to its antioxidant properties, EVO oil was particularly efficient in restoring normal levels of membrane fluidity, which, on the contrary, were reduced in the presence of inflammation. In conclusion, these data support the hypothesis that these Mediterranean oils could play a major role in the modulation of low-grade inflammation and metabolic syndrome prevention. However, NS oil seems to be more efficient in the control of proinflammatory cytokines, whereas EVO oil better helps to counteract redox imbalance. Further studies that elucidate the nutrigenomic properties of local produce might help to promote regional the production and consumption of high-quality food, which could also help the population to maintain and promote health.

Effect of lipid type, dispersed phase volume fraction and emulsifier on the physicochemical properties of nanoemulsions fortified with conjugated linoleic acid (CLA): Process optimization and stability assessment during storage conditions

Conjugated linoleic acid (CLA) although gains recognition as food supplement due to various physiological activities, its water insolubility and oxidative instability limit its applications in food systems. Oil-in-water nanoemulsions based on extra virgin olive (EVOO) or pomace oil (OPO) are considered excellent delivery systems offering high protection and controlled release of CLA. In the present study, CLA-loaded nanoemulsions were prepared using ultrasonic homogenization approach and the effect of storage temperature (25 °C or 4 °C) on the nanoemulsion physical and chemical stability was investigated. All formulations demonstrated good long-term physical and chemical stability; mean droplet diameter <300 nm during 60 days-storage (4 °C and 25 °C). CLA degradation (RCLA %) was lower in the nanoemulsions with 8 wt% lipid phase; specifically, nanoemulsions with 8 wt% olive pomace oil and 6 wt% Tween 20 (RCLA = 80.154% at 25 °C and RCLA = 84.165% 4 °C) after 2 months. Response surface methodology was used to optimize the preparation conditions (type and concentration of lipid phase and emulsifier) at different storage conditions and predict the optimum values of mean droplet diameter, ζ-potential and CLA retention. The minimum lipid concentration (4 wt%) exhibited the optimum values at both environment and refrigerated storage for EVOO nanoemulsions. However, nanoemulsion with 8 wt% OPO and 4 wt% Tween 40 (71.843% at 25 °C) or 6 wt% Tween 20 were the optimum condition regarding the highest chemical stability.

Association of Taste Perception for Sweet, Salt, Sour, Bitter and Umami and Food Intake Among Community-dwelling Adults in the PREDIMED-PLUS Trial (P18-065-19)

ObjectivesTo investigate the association between taste perception for sweet, salt, sour, bitter and umami and food category intakes. We hypothesized that greater taste perception will be inversely associated with the amount consumed. MethodsA cross-sectional baseline analysis was performed on community-dwelling overweight adults with metabolic syndrome (N = 367, 55–75y) from the PREDIMED-PLUS Trial, University of Valencia Center, Spain. Taste perception was determined by challenging subjects with standard solutions of sweet, salt, sour, bitter and umami (400 mM sucrose, 200 mM NaCl, 34 mM citric acid, 5.6 mM phenylthiocarbamide (PTC), 200 mM monopotassium glutamate, respectively) and evaluated on a 0–5 scale. Outcomes included intake (servings/week) of food categories derived from a validated food frequency questionnaire: fruit (citrus/non-citrus/nuts), vegetables (cruciferous/non-cruciferous), protein (eggs/fish[fresh/shell/canned]/meat[processed/unprocessed]), grains (legumes/refined/whole), dairy (regular/low- & no-fat) and oils (extra virgin olive (EVOO)/olive/vegetable). Multivariable linear regression models were used to assess associations of perception for each taste and consumption of each food category (untransformed or transformed, for normality). ResultsAfter controlling for age, sex, diabetes, smoking, physical activity and energy intake, sweet was inversely associated with vegetables (β = −1.1; 95% CI = [−2.0, −0.2]), particularly non-cruciferous (β = −1.0; P = 0.02), and citrus fruit (β = −0.5; P < 0.01); salt was positively associated with fruit (β = 1.0; 95% CI = [0.04, 1.9]), particularly non-citrus (β = 0.6; P = 0.03), and olive oil (β = 1.1; P = 0.02) but negatively associated with EVOO (β = −1.4; P = 0.02); sour was positively associated with cruciferous vegetables (β = 0.1; P = 0.04); bitter was inversely associated with canned fish (β = −0.1; P = 0.03); and umami was positively associated with non-cruciferous vegetables (β = 0.7; P = 0.04) and inversely associated with regular dairy (β = −0.4; P = 0.04). ConclusionsOur hypothesis was rejected. Taste perception for sweet, salt, sour, bitter and umami differentially affected intake of various food categories; suggesting a role of taste perception in diet quality, energy balance and diet-related chronic diseases. Funding SourcesThis study was funded by the ARS/USDA, and the Spanish Ministry of Health (Instituto de Salud Carlos III), SAF2016–80,532-R, and the Generalitat Valenciana.

The effect of oil type and solvent quality on the rheological behavior of zein stabilized oil-in-glycerol emulsion gels

The aim of this study was to assess the effect of oil type and solvent quality on the structure formation and rheological properties of zein-stabilized oil-in-glycerol emulsion gels. To change the interactions within the system, four types of oil (medium chain triglyceride (MCT) oil, sunflower oil, extra virgin olive (EVO) oil, and castor oil) with different polarity were used, and the solvent quality was modified by temperature and water addition. In all cases, emulsion gels were obtained with G' > G''. At each protein concentration and oil content, the gel strength and crossover strain γco increased with an increase in oil polarity, indicating the formation of a stronger gel structure and higher stability against structure breakdown. These results are related to the fact that a higher oil polarity decreases the oil-protein hydrophobic interactions and thereby increasing the interactions between the proteins to form a strong network in the continuous phase. In addition, water addition to the continuous phase enhanced the gel strength and the resistance against structure breakdown for more apolar MCT oil, while the opposite results were observed for the more polar castor oil. The zein-based emulsion gels showed a thermo-responsive behavior, and different responses in structure collapse and rearrangements during heating and cooling were found for different oils. These simple approaches form an interesting route to tune the rheological properties of zein-based emulsion gels.

Kinetic Study of the Quenching Reaction of Singlet Oxygen by Eight Vegetable Oils in Solution.

A kinetic study of the reaction of singlet oxygen (1O2) with eight vegetable oils 1-8 containing different concentrations of tocopherols (Tocs) and tocotrienols (Toc-3s) was performed. The second-order rate constants (kQ) for the reaction of 1O2 with vegetable oils 1-8 (rice bran, perilla, rape seed, safflower, grape seed, sesame, extra virgin olive, and olive oils) were measured in ethanol/chloroform/D2O (50:50:1, v/v/v) solution at 35°C using UV-vis spectrophotometry. Furthermore, comparisons of kQ values determined for the above oils 1-8 with the sum of the product {∑kQAO-i [AO-i]/105} of the kQAO-i values obtained for each antioxidant (AO-i) and concentration (in mg/100 g) ([AO-i]/105) of AO-i (Tocs and Toc-3s) contained in the oils 1-8 were performed. The observed kQ values were not reproduced by the kQ values calculated using only the concentrations of the four Tocs and Toc-3s. These results suggest that the contribution of fatty acids contained in the oils 1-8 is also necessary to fully explain the kQ values. Recently, the second-order rate constants (kS) for the reaction of aroxyl radical (ArO・) with the same vegetable oils 1-8 were measured in the same solvent at 25℃ using stopped-flow spectrophotometry (Ref. 23). The kS values obtained could be well explained as the sum of the product {Σ kSAO-i [AO-i]/105} of the kSAO-i and the [AO-i]/105 of AO-i (Tocs and Toc-3s) contained in the vegetable oils.