Developing FT-NIR and PLS1 Methodology for Predicting Adulteration in Representative Varieties/Blends of Extra Virgin Olive Oils

It was previously demonstrated that Fourier transform near infrared (FT‐NIR) spectroscopy and partial least squares (PLS1) were successfully used to assess whether an olive oil was extra virgin, and if adulterated, with which type of vegetable oil and by how much using previously developed PLS1 calibration models. This last prediction required an initial set of four PLS1 calibration models that were based on gravimetrically prepared mixtures of a specific variety of extra virgin olive oil (EVOO) spiked with adulterants. The current study was undertaken after obtaining a range of EVOO varieties grown in different countries. It was found that all the different types of EVOO varieties investigated belonged to four distinct groups, and each required the development of additional sets of specific PLS1 calibration models to ensure that they can be used to predict low concentrations of vegetable oils high in linoleic, oleic, or palmitic acid, and/or refined olive oil. These four distinct sets of PLS1 calibration models were required to cover the range of EVOO varieties with a linoleic acid content from 1.3 to 15.5 % of total fatty acids. An FT‐NIR library was established with 66 EVOO products obtained from California and Europe. The quality and/or purity of EVOO were assessed by determining the FT‐NIR Index, a measure of the volatile content of EVOO. The use of these PLS1 calibration models made it possible to predict the authenticity of EVOO and the identity and quantity of potential adulterant oils in minutes.     

Novel,Rapid Identification,and Quantification of Adulterants in Extra Virgin Olive Oil Using Near‐Infrared Spectroscopy and Chemometrics

A new, rapid Fourier transform near infrared (FT‐NIR) spectroscopic procedure is described to screen for the authenticity of extra virgin olive oils (EVOO) and to determine the kind and amount of an adulterant in EVOO. To screen EVOO, a partial least squares (PLS1) calibration model was developed to estimate a newly created FT‐NIR index based mainly on the relative intensities of two unique carbonyl overtone absorptions in the FT‐NIR spectra of EVOO and other mixtures attributed to volatile (5280 cm^?1) and non‐volatile (5180 cm^?1) components. Spectra were also used to predict the fatty acid (FA) composition of EVOO or samples spiked with an adulterant using previously developed PLS1 calibration models. Some adulterated mixtures could be identified provided the FA profile was sufficiently different from those of EVOO. To identify the type and determine the quantity of an adulterant, gravimetric mixtures were prepared by spiking EVOO with different concentrations of each adulterant. Based on FT‐NIR spectra, four PLS1 calibration models were developed for four specific groups of adulterants, each with a characteristic FA composition. Using these different PLS1 calibration models for prediction, plots of predicted vs. gravimetric concentrations of an adulterant in EVOO yielded linear regression functions with four unique sets of slopes, one for each group of adulterants. Four corresponding slope rules were defined that allowed for the determination of the nature and concentration of an adulterant in EVOO products by applying these four calibration models. The standard addition technique was used for confirmation.     

Evaluation of MALDI-TOF/MS Technology in Olive Oil Adulteration

Adulteration of extra virgin olive oil (EVOO) by addition of other vegetable oils or lower-grade olive oils is a common problem of the oil market worldwide. Therefore, we developed a fast protocol for detection of EVOO adulteration by mass spectrometry fingerprinting of triacylglycerol (TAG) profiles based on MALDI-TOF/MS. For that purpose, EVOO TAG profiles were compared with those of edible sunflower oil and olive oil composed of refined olive oil and virgin olive oils. Adulteration of EVOO was simulated by addition of sunflower and mixture of refined olive oil and virgin olive oils at 1, 10 and 20% w/w. Results of mass spectrometry TAG profiling were compared with routinely assessed K values for identification of adulteration. MALDI-TOF/MS technology coupled with statistical analysis was proven as useful for detection of adulteration in EVOO at a rate down to 1%. In contrast, standard spectrophotometric methods failed to identify minor adulterations. In addition, the ability of MALDI-TOF/MS in detection of adulteration was tested on EVOO samples from different geographical regions. Results demonstrated that MALDI-TOF/MS technology coupled with statistical analysis is able to distinguish adulterated oils from other EVOO.     

Chemometric Studies on zNose™ and Machine Vision Technologies for Discrimination of Commercial Extra Virgin Olive Oils

The aim of this study was to classify Turkish commercial extra virgin olive oil (EVOO) samples according to geographical origins by using surface acoustic wave sensing electronic nose (zNose?) and machine vision system (MVS) analyses in combination with chemometric approaches. EVOO samples obtained from north and south Aegean region were used in the study. The data analyses were performed with principal component analysis class models, partial least squares‐discriminant analysis (PLS‐DA) and hierarchical cluster analysis (HCA). Based on the zNose? analysis, it was found that EVOO aroma profiles could be discriminated successfully according to geographical origin of the samples with the aid of the PLS‐DA method. Color analysis was conducted as an additional sensory quality parameter that is preferred by the consumers. The results of HCA and PLS‐DA methods demonstrated that color measurement alone was not an effective discriminative factor for classification of EVOO. However, PLS‐DA and HCA methods provided clear differentiation among the EVOO samples in terms of electronic nose and color measurements. This study is significant from the point of evaluating the potential of zNose? in combination with MVS as a rapid method for the classification of geographically different EVOO produced in industry.     

Biochemical Characterization of Arbequina Extra Virgin Olive Oil Produced in Turkey

Varieties of the olive cultivar Arbequina have recently been cultivated in Turkey. The objective of the study is to characterize and evaluate extra‐virgin olive oils (EVOO) produced from Arbequina grown in the Aegean and Mediterranean regions of Turkey. Major and minor components such as carotenoids, squalene, phenolics and tocopherols were studied to assess their effects on product quality and health benefits. The samples, identified as ArbqI and ArbqA, were from the Izmir and Adana provinces, respectively. Samples were analyzed by GC‐FID to determine fatty acid composition, sterol composition, TAG profile and squalene content. Individual phenolic fractions were analyzed by LC–MS/MS and tocopherol isomers were determined by HPLC. According to the results obtained from this study; Total phenolic content (TPC) of the samples were 454.68 and 50.86 mg Gallic acid/kg oil for ArbqI and ArbqA, respectively. Hydroxytyrosol and tyrosol were determined to be the main phenols. The major tocopherol isomer found in ArbqI and ArbqA was α‐tocopherol with levels of 179.55 and 202.5 mg/kg oil, respectively. β‐Carotene levels in both samples were similar at 0.2 mg/kg. Findings of this study were compared with the literature on Arbequina olive oil produced in different countries. It was determined that Arbequina olive oil of high quality can be produced in Turkey, especially in the Aegean region.     

Authenticity Assessment of Extra Virgin Olive Oil: Evaluation of Desmethylsterols and Triterpene Dialcohols

Extra virgin olive oil (EVOO) has a long history of economic adulteration, the detection of which presents significant challenges due to the diverse composition of cultivars grown around the world and the limitations of existing methods for detecting adulteration. In this study, using Method COI/T.20/Doc. No. 30/Rev. 1 of the International Olive Council, the authenticity of 88 market samples of EVOO was evaluated by comparing total sterol contents, desmethylsterol composition, and contents of triterpene dialcohols (erythrodiol and uvaol) with purity criteria specified in the United States Standards for grades of olive oil and olive‐pomace oil. Three of the 88 samples labeled as EVOO failed to meet purity criteria, indicating possible adulteration with commodity oil and/or solvent‐extracted olive oil. Detection of adulteration was also evaluated by spiking an EVOO sample with commodity oil at the 10 % level. As expected, eight of the spiked samples (canola, corn, hazelnut, peanut, safflower, soybean, and sunflower oils, and palm olein) failed to meet purity criteria. Two of the three samples spiked with 10 % hazelnut oil went undetected for adulteration. Overall, a low occurrence rate of adulteration (<5 %), based on purity criteria for desmethylsterols and triterpene dialcohols, was detected for the 88 products labeled as EVOO.     

The Effect of Different Cold Storage Conditions on the Compositions of Extra Virgin Olive Oil

Storage conditions can affect the stability and quality of extra virgin olive oil (EVOO). While many studies have reported the influence of high temperature and light exposure during storage, little is known on the influence of the cold storage. The aim of this study was to evaluate the effect of different storage conditions (25, 4.5 and ?27 °C) on the various compositions of EVOO and to determine if cold storage will prolong shelf‐life by retarding hydrolysis and oxidation. The changes of quality indices (FFA, PV, and UV) and natural antioxidants such as α‐tocopherol and phenolic compounds were evaluated periodically during storage. The characterization and quantification of phenolics were achieved by ultra‐performance liquid chromatography—diode array detector (UPLC‐DAD). In addition, 1, 2‐diacylglycerols (DAGs), pyropheophytin A (PPP) were measured to indicate thermal degradation during storage.     

Biochemical Characterization of Turkish Extra Virgin Olive Oils from Six Different Olive Varieties of Identical Growing Conditions

Extra virgin olive oils were extracted from six different major olive cultivars (Gemlik, Ayvalik, Domat, Akhisar, Memecik, Arbequina) cultivated in the Aegean region of Turkey. Fatty acid, sterol and tocopherol compositions were analyzed and the results were compared by multivariate statistical analysis. Olive samples were collected from the same orchard in order to limit the contribution of parameters such as climate, soil quality and agricultural practices to the total variance of chemical composition of olive oils. Principal component analysis (PCA) showed that cultivars can be clearly distinguished on the basis of fatty acid and sterol composition. It is of interest to note that palmitoleic acid content of Arbequina, a Spanish cultivar, is significantly (p < 0.05) higher than the local Turkish cultivars in question and it is the only olive sample whose palmitoleic acid concentration is higher than that of the stearic acid concentration, exhibiting a divergent composition from the local Turkish cultivars. β‐Sitosterol and Δ5‐avenasterol contents of the oils are significantly correlated (r = ?0.989, p < 0.05) and this results in a discriminative axis on the PCA loading plot. Tocopherol composition was relatively insufficient in discriminating the olive varieties. Regarding tocopherol compositions Gemlik cultivar is distinguished from other cultivars with its γ‐tocopherol content, which is in average two times higher than that of other cultivars. The result of the present compositional study provides important data which can be used for olive oil authenticity studies in Turkey.     

The Use of FTIR Spectroscopy and Chemometrics for Rapid Authentication of Extra Virgin Olive Oil

The authenticity of high value edible fats and oils including extra virgin olive oil (EVOO) is an emerging issue, currently. The potential employment of Fourier transform infrared (FTIR) spectroscopy in combination with chemometrics of multivariate calibration and discriminant analysis has been exploited for rapid authentication of EVOO from canola oil (Ca‐O). The optimization of two calibration models of partial least square (PLS) and principle component regression was performed in order to quantify the level of Ca‐O in EVOO. The chemometrics of discriminant analysis (DA) was used for making the classification between pure EVOO and EVOO adulterated with Ca‐O. The individual oils and their blends were scanned on good contact with ZnSe crystals in horizontal attenuated total reflectance, as a sampling technique. The wavenumbers of 3,028–2,985 and 1,200–987 cm^?1 were used for quantification and classification of EVOO adulterated with Ca‐O. The results showed that PLS with normal FTIR spectra was well suited for quantitative analysis of Ca‐O with a value of the coefficient of determination (R²) > 0.99. The error, expressed as root mean square error of calibration obtained was relatively low, i.e. 0.108 % (v/v). DA can make the classification between pure EVOO and that adulterated with Ca‐O with one misclassified reported.     

Synthesis of Infant Formula Fat Analogs Enriched with DHA from Extra Virgin Olive Oil and Tripalmitin

Structured lipids (SLs) containing palmitic, oleic, and docosahexaenoic acids for possible use in infant formulas were synthesized by enzymatic acidolysis reactions. The substrates used were tripalmitin, extra virgin olive oil free fatty acids (EVOOFFA), and docosahexaenoic acid single cell oil free fatty acids (DHASCOFFA) in 1:1:1, 1:2:1, 1:3:2, 1:4:2, and 1:5:1 molar ratios. Reactions were carried out at 65 °C for 24 h using Lipozyme^® TL IM lipase. The products were analyzed for total and positional fatty acids by GC-FID, triacylglycerol (TAG) molecular species by HPLC-ELSD, and thermal behavior by DSC. The SLs, SL132, SL142, and SL151 had desirable fatty acid distribution for infant formula use with nearly 60 mol% palmitic acid at the sn-2 position and oleic acid predominantly at the sn-1,3 positions. The total DHA content of SL132, SL142, and SL151 were 7.54, 6.72, and 5.89 mol%, respectively. The major TAG molecular species in the SLs were PPP, OPO, and PPO. The melting completion temperature of SL132 was 37.1, 35.2 °C in SL142, and 32.9 °C in SL151. The SLs synthesized in this study have potential use in infant formulas.     

Detection of Soft‐Deodorized Olive Oil and Refined Vegetable Oils in Virgin Olive Oil Using Near Infrared Spectroscopy and Traditional Analytical Parameters

The European Parliament identifies virgin olive oil (VOO) as one of the foods which are often subject to fraudulent activities. Possibilities of adulteration are the application of illegal soft deodorization of extra virgin olive oil (EVOO) or the commercialization of blends of EVOO with soft‐deodorized EVOO or refined vegetable oils. Despite the search for possibilities to prove the illegal soft deodorization of EVOO or the addition of cheaper vegetable oils to EVOO, suitable methods are still missing. Therefore, the aim of the study is to develop a new analytical and statistical approach addressing detection of mild deodorization or addition of refined foreign oils. For this purpose, VOOs are treated in lab‐scale for 1 h up to 28 days at different temperatures (20, 50, 60, 80,100, 110, and 170 °C) in order to simulate and study the effect of heat treatment on known analytical parameters by near infrared spectroscopy (NIR). A logit regression model enabling the calculation of the probability for a heat treatment is developed. This new methodology allows detecting both soft deodorized olive oils and blends of EVOO with cheaper full refined vegetable oils. Adding only 10% of full refined oil could be detected in extra VOO. Practical Applications: NIR methods combined with chemometrics have become one of the most attractive analytical tools to control quality of food. It is a simple, precise, and rapid method. All relevant analytical parameters of oxidative and thermal fat degradation can be determined in a single run and be used to detect adulterated virgin olive oils (VOOs). The use of a simple equation developed from the logistic regression using peroxide value, K‐values, p‐anisidine value, pyropheophytine, 1,2‐diacylglycerols, total polar compounds and monomeric oxidized triacylglycerols, and other well‐known parameters allows to detect mild deodorized olive oils or also blends of VOO with soft‐deodorized ones or the addition of low amounts of foreign vegetable oils. This technique has potential to be used as a screening method for the detection of adulterated olive oils using both the traditional laboratory methods and the corresponding NIR‐methods.     

A Comparative Study of O/W Nanoemulsions Using Extra Virgin Olive or Olive‐Pomace Oil: Impacts on Formation and Stability

Nanoemulsions are considered an innovative approach for industrial food applications. The present study explored the potential use of olive‐pomace oil (OPO) for oil‐in‐water (o/w) nanoemulsion preparations and compared the effectiveness of extra virgin olive oil (EVOO) and OPO at nanoemulsion formulations. The ternary‐phase diagrams were constructed and the o/w nanoemulsions properties were evaluated in relation to their composition. The results showed that it is possible to form OPO nanoemulsions using Polysorbate 20 or Polysorbate 40. Nanoemulsions with EVOO and OPO presented desirable properties, in terms of kinetic stability (emulsion stability index % [ESI%]), mean droplet diameter (MDD), polydispersity index (PDI), ζ‐potential, viscosity, and turbidity. EVOO exhibited lower surface and interfacial tension forming nanoemulsions with a high ESI% and a low MDD. However, OPO led to nanoemulsions with a high ESI% but with a higher MDD. It was observed that by increasing the emulsifier concentration the MDD decreased, while increasing the dispersed phase concentration led to a higher MDD and a lower ESI%. Finally, nanoemulsions with the smallest MDD (99.26 ± 4.20 nm) and PDI (0.236 ± 0.010) were formed using Polysorbate 40, which presented lower surface and interfacial tension. Specifically, the nanoemulsion with 6 wt% EVOO and 6 wt% Polysorbate 40 demonstrated an interfacial tension of 51.014 ± 0.919 mN m^?1 and an MDD of 99.26 ± 4.20 nm. However, the nanoemulsion with 6 wt% OPO and 8 wt% Polysorbate 20 presented an interfacial tension of 54.308 ± 0.089 mN m^?1 and an MDD of 340.5 ± 7.1 nm.     

First Application of Newly Developed FT-NIR Spectroscopic Methodology to Predict Authenticity of Extra Virgin Olive Oil Retail Products in the USA

Economically motivated adulteration (EMA) of extra virgin olive oils (EVOO) has been a worldwide problem and a concern for government regulators for a long time. The US Food and Drug Administration (FDA) is mandated to protect the US public against intentional adulteration of foods and has jurisdiction over deceptive label declarations. To detect EMA of olive oil and address food safety vulnerabilities, we used a previously developed rapid screening methodology to authenticate EVOO. For the first time, a recently developed FT-NIR spectroscopic methodology in conjunction with partial least squares analysis was applied to commercial products labeled EVOO purchased in College Park, MD, USA to rapidly predict whether they are authentic, potentially mixed with refined olive oil (RO) or other vegetable oil(s), or are of lower quality. Of the 88 commercial products labeled EVOO that were assessed according to published specified ranges, 33 (37.5%) satisfied the three published FT-NIR requirements identified for authentic EVOO products which included the purity test. This test was based on limits established for the contents of three potential adulterants, oils high in linoleic acid (OH-LNA), oils high in oleic acid (OH-OLA), palm olein (PO), and/or RO. The remaining 55 samples (62.5%) did not meet one or more of the criteria established for authentic EVOO. The breakdown of the 55 products was EVOO potentially mixed with OH-LNA (25.5%), OH-OLA (10.9%), PO (5.4%), RO (25.5%), or a combination of any of these four (32.7%). If assessments had been based strictly on whether the fatty acid composition was within the established ranges set by the International Olive Council (IOC), less than 10% would have been identified as non-EVOO. These findings are significant not only because they were consistent with previously published data based on the results of two sensory panels that were accredited by IOC but more importantly each measurement/analysis was accomplished in less than 5 min.     

Total Phenolics of Virgin Olive Oils Highly Correlate with the Hydrogen Atom Transfer Mechanism of Antioxidant Capacity

Polar extracts of extra‐virgin olive oils (EVOO) contain a large number of phenolic compounds with antioxidant properties. The antioxidant capacity can be measured by different reaction mechanisms, as the single electron transfer (SET) or the hydrogen atom transfer (HAT). In this work, the total phenolic content (TPC) by the Folin‐Ciocalteu method and its correlation with four antioxidant capacity assays (FRAP, ABTS, DPPH^? and ORAC) were evaluated for EVOO polar extracts. It was observed that the higher the total phenolic compounds in the EVOO extracts, the higher the antioxidant capacities, regardless of the method employed. The reaction mechanism observed for TPC by Folin‐Ciocalteu method and also for FRAP, ABTS and DPPH^? antioxidant capacity assays is a single electron transfer, thus, a high correlation among their results is expected. However, the correlation between TPC and ORAC results was also high and significant, allowing to conclude that EVOO phenolic compounds are able to react by the hydrogen atom transfer mechanism, which indicates that they can act as effective radical chain‐breaking antioxidants. These results suggest that, for the EVOO polar extracts, TPC by Folin‐Ciocalteu and ORAC assays could be sufficient to evaluate their in vitro antioxidant capacity.     

Effect of Light Exposure on the Quality and Phenol Content of Commercial Extra Virgin Olive Oil during 12-Month Storage

Storage conditions influence the maximum time for which the composition and sensory characteristics of olive oils can be guaranteed. The purpose of this research was to study the quality and phenol content of extra virgin olive oil (EVOO) after storage for 1 year in different types of containers under darkness or light. Three Spanish cultivars with quantitatively different phenol contents were selected for the study. Storage under light conditions impaired the physicochemical and sensorial properties of the three cultivars, and reduced total phenolics, but there was an increase in hydroxytyrosol and tyrosol concentrations. It also markedly decreased their total phenolic content, especially when kept in polyethylene containers exposed to light, with reductions ranging from 4.28% for vanillic acid in Picual oils stored in dark glass containers under dark conditions to 97.82% for ferulic acid in Arbequina oils stored in polyethylene containers under light conditions. There was a reduced concentration of flavonoid and lignan concentrations after 1 year of storage, with the greatest decrease (98.01% of initial content) being observed for in the flavonoid apigenin. These results indicate that EVOO should be stored in dark glass containers under dark conditions for the optimal preservation of its quality and phenol content.     

Adulteration and Presence of Polycyclic Aromatic Hydrocarbons in Extra Virgin Olive Oil Sold on the Brazilian Market

Seventy samples sold in the Brazilian market as extra virgin olive oil (EVOO) were evaluated for the presence of the 13 polycyclic aromatic hydrocarbons (PAH) classified as carcinogenic and genotoxic by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), to verify if the products were adulterated and to evaluate if there is a correlation between PAH presence and adulteration. PAH were detected in 93% of the samples, with summed levels varying from not detected to 41.10 μg/kg. Five samples showed BaP concentration above acceptable levels set by European legislation and by Brazilian regulation (2.0 μg/kg) and 7 presented PAH4 levels above the limit set by European legislation (10.0 µg/kg). The levels of fatty acid composition, sterols content, stigmastadiene and specific extinction did not comply with both Brazilian and International Olive Council (IOC) standards in 18, 31, 30 and 21% of the samples, respectively. The tolerance levels for these analyses in the Brazilian standards are 55.0–83.0 g/100 g (oleic acid), 3.5–21.0 g/100 g (linoleic acid), ≤0.05 g/100 g (trans-oleic acid), ≤0.05 g/100 g (trans-linoleic + trans-linolenic acid), ≤0.15 mg/kg (stigmastadiene), ≤2.50 (K232), ≤0.22 (K270), ≤0.01 (?K), 1000–1600 mg/kg (Σ sterols). Results indicate that 19 samples were adulterated. According to principal component analysis, samples were distinguished as: (1) EVOO with addition of vegetable oil from another source, (2) EVOO with addition of refined oil and (3) samples possibly not adulterated. The variable ΣPAH was related mainly to samples of EVOO with addition of vegetable oil from another source.     

Studies on the Detection of Oleuropein from Extra Virgin Olive Oils Using Enzymatic Biosensors

Oleuropein (OLEU) is an important indicator of the quality and authenticity of extra virgin olive oils (EVOO). Electrochemical sensors and biosensors for the detection of oleuropein can be used to test the adulteration of extra virgin olive oils. The present study aimed at the qualitative and quantitative determination of oleuropein in commercial EVOO samples by applying electrochemical techniques, cyclic voltammetry (CV) and square wave voltammetry (SWV). The sensing devices used were two newly constructed enzyme biosensors, supported on single-layer carbon-nanotube-modified carbon screen-printed electrode (SPE/SWCNT) on whose surface tyrosinase (SPE/SWCNT/Tyr) and laccase (SPE/SWCNT/Lac) were immobilized, respectively. The active surfaces of the two biosensors were analyzed and characterized by different methods, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FTIR) and the results confirmed the efficient immobilization of the enzymes. SPE/SWCNT/Tyr was characterized by a low detection limit (LOD = 9.53 × 10⁻⁸ M) and a very good sensitivity (0.0718 μA·μM⁻¹·cm⁻²) over a wide linearity range from 0.49 to 11.22 μM. The process occurring at the biosensor surface corresponds to kinetics (h = 0.90), and tyrosinase showed a high affinity towards OLEU. The tyrosinase-based biosensor was shown to have superior sensitive properties to the laccase-based one. Quantitative determination of OLEU in EVOOs was performed using SPE/SWCNT/Tyr and the results confirmed the presence of the compound in close amounts in the EVOOs analysed, proving that they have very good sensory properties.     

Clarifications of the Carbonyl and Water Absorptions in Fourier Transform Near Infrared Spectra from Extra Virgin Olive Oil

The Fourier transform near infrared (FT-NIR) spectrum of extra virgin olive oils (EVOO) shows two minor carbonyl absorptions at 5280 and 5180 cm^–1 that has been used to assess their authenticity. To establish components absorbing at 5280 cm^–1, volatile aldehydes and ketones, triacylglycerol (TAG), diacylglycerols (DAG), free fatty acids (FFA), phenolics, and water are investigated and sometimes added to refined olive oil (ROO). Except TAG, the remaining carbonyls contribute to 5280 cm^–1 by broadening peak. Water absorption is demonstrated by its removal using Na₂SO₄ or deuterium oxide addition; FT-NIR spectral changes are reconstituted by water addition. Water absorption depends on being free or complexed with polar compounds in oil. The size of absorption is not related to abundance, but on unique absorption specificity of components; water shows the strongest absorption. Heat removes water and volatiles, leaving behind DAG, FFA, and phenolics, and makes it possible to differentiate absorption of water, volatile and non-volatile carbonyls. Cloudy olive oils are analyzed using FT-NIR methodology after warming for 3 min at 50 °C. FT-NIR index values are replaced by a new calibration model based on correlating gravimetric mass loss of water plus volatiles with spectral changes. The FT-NIR methodology is expanded to include EVOOs with 15.5% to 21% linoleic acid. Practical Applications: Testing for authenticity of EVOOs remains a challenge because adulterations continue to be a problem due to economic gains. Spectroscopy methods, specifically FT-NIR, are much preferred to targeted chemical methods because they measure all constituents in products and are non-destructive and fast. The current universal FT-NIR methodology assesses 13 different parameters: five major FAs, and the DAG and FFA contents. The FT-NIR index value measuring the content of moisture plus volatiles is now replaced by a gravimetric determination. The methodology identifies four major types of adulterants, high in oleic acid, linoleic acid, palm olein or ROO. The composition of olive oils makes it necessary to develop five oil-specific groups, but cloudy samples still need to be clarified by slight warming before measuring. The value of this universal FT-NIR methodology will increase after being adopted by commercial and in regulatory settings.     

Ketogenic Diet Based on Extra Virgin Coconut Oil Has No Effects in Young Wistar Rats With Pilocarpine‐Induced Epilepsy

This study evaluated the effects of a ketogenic diet (KD) based on extra virgin coconut oil (Cocos nucifera L., VCO), on the treatment of epileptic rats. Two sets of experiments were conducted. First, male Wistar rats underwent induction of status epilepticus (SE) with the administration of pilocarpine intraperitoneally 21 animals reached spontaneous recurrent seizures (SRS) and were randomly allocated to the dietary regimens and video‐monitored for 19 days. In the second experiment, 24 animals were randomized immediately after the induction of SE and followed for 67 days. Diets were as follows: Control (AIN‐93G; 7% lipid), KetoTAGsoya (KD based on soybean oil; 69.79% lipid), and KetoTAGcoco (KD based on VCO; 69.79% lipid). There were no differences in the latency to the first crisis, total frequency, and duration of the SRS between groups in 2 experiments. The data suggest no effects of KD, with or without VCO, in rats with pilocarpine‐induced epilepsy.     

Physical,Chemical, and Biological Characterization of Veiled Extra Virgin Olive Oil Turbidity for Degradation Risk Assessment

Six different 300 kg batches of olive fruits are processed and the resulting six 20 kg batches of oil are collected at the end of the “decanter.” These batches of oil are subjected to four different water and solid particle separation treatments so as to obtain the following oil samples: veiled oil, filtered oil, “solid particle‐only” oil, and “water‐only” oil. The applied separation treatments show that water content has an important role in the degree of turbidity. High water content values (>0.2% w/w) are related to water activity values of >0.6 which are suitable for chemical and enzymatic reactions. The veiled oil samples are contaminated by microorganisms, but non‐proportional behavior occurs between the microbial cell count and the water and solid particle contents. Practical Applications: The results of this study recommend a multi‐approach method to characterize turbidity, based on control markers such as the degree of turbidity, water content and water activity, solid particle content, microbial contamination, and phenolic compound content. In this way, each degree of turbidity can be associated with a different level of risk of veiled extra virgin olive oil degradation during shelf life.