Fast Automated Determination of Total Tocopherol Content in Virgin Olive Oil Using a Single Multicommuted Luminescent Flow Method

Tocopherols are natural fluorophores of great importance for the characterization and authentication of virgin olive oil. Herein, a single automatic multicommuted flow method has been developed for the determination of total tocopherol content as well as the semi-quantitative estimation of α-tocopherol in extra virgin olive oil (EVOO) samples. Only appropriate dilution of samples with 2-propanol was necessary for their direct analysis by a multicommuted flow injection (MCFIA) manifold based on three solenoid valves with fluorescence detection. The peak height at λ _em = 330 nm (emission) with λ _exc at 296 nm was used as analytical signal. Linear response was observed within the range from 50 to 350 mg of tocopherols (expressed as α-tocopherol kg^?1 olive oil), suitable to cover the usual range for tocopherols in (extra) virgin olive oil ((E)VOO)). The results were consistent with those obtained by reversed-phase HPLC reference method, whereas the analysis time was significantly reduced. The sample frequency of the proposed automatic method was close to 40 samples h^?1, in contrast to typically 15–30 min required by HPLC. The method is fast, straightforward, cost-effective, and easy to implement in routine laboratories for screening purposes.     

Bioavailability,rheology, and sensory evaluation of mayonnaise fortified with vitamin D encapsulated in protein-based carriers

Vitamin D lost its functionality during processing and storage, thus, encapsulation with proteins is desirable to preserve bioactivity. The aim of the current study was to develop encapsulated vitamin D fortified mayonnaise (VDFM) using whey protein isolates (WPI) and soy protein isolates (SPI) as encapsulating materials in three different formulations, that is, 10% WPI, 10% SPI, and 5/5% WPI/SPI. Increased shear stress decreased the apparent viscosity along with significant effects on the loss modulus of VDFM. WPI encapsulates showed better results as compared to SPI. WPI based VDFM (M₁) depicted the best results in terms of size and dispersion uniformity of oil droplets. Hue angle and total change differed significantly among treatments. The highest value for overall acceptability was acquired by M₃ (5:5%WPI:SPI-encapsulates) thus proceed for in vivo trials. Serum vitamin D level was significantly higher in the encapsulated VDFM rat group (58.14 ± 6.29 nmol/L) than the control (37.80 ± 4.98 nmol/L). Conclusively, WPI and SPI encapsulates have the potential to improve the stability and bioavailability of vitamin D.     

Screening of Over 600 Pesticides,Veterinary Drugs,Food-Packaging Contaminants,Mycotoxins, and Other Chemicals in Food by Ultra-High Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (UHPLC-QTOFMS)

In this article, an accurate mass multiresidue screening method has been developed for the determination of over 630 multiclass food contaminants in different matrices using ultra-high performance liquid chromatography/(quadrupole)-time-of-flight mass spectrometry. The compounds included in the study were 426 pesticides, 117 veterinary drugs, 42 food-packaging contaminants, 21 mycotoxins, 10 perfluorinated compounds, 9 nitrosamines, and 5 sweeteners. The separation was carried out by liquid chromatography using a C₁₈ column (50 mm × 2.1 mm, 1.8 μm particle size). The identification of the targeted species was accomplished using accurate masses of the targeted ions (protonated or deprotonated molecule) along with retention time data and characteristic fragment ion for reliable identification, using specific software for automated data mining and exploitation. The performance of the screening method was validated in terms of linearity, matrix effect, and limits of quantification for three representative food matrices (tomato, orange, and baby food) using a generic sample treatment based on liquid partitioning with acetonitrile (QuEChERS). The overall method performance was satisfactory with limits of quantification lower than 10 μg kg ^?1 for the 44 % of studied compounds. In some cases (ca. 10–15 % of the pesticides depending on the matrix tested, maximum residue levels were not fulfilled). In orange, 15 % of the compounds displayed LOQs above the maximum residue levels (MRLs) set for the studied pesticides, which can be partially attributed to matrix effects. Moderate signal suppression was observed in the three matrices tested in most cases, being orange the matrix which produced the highest matrix effect and baby food the lowest one.     

Influence of malaxation temperature and time on the quality of virgin olive oils

To study the influence of operative conditions adopted during the malaxation of pastes on the quality of resulting oils, we compared sensory characteristics, secoiridoid compounds and the volatile composition of oils extracted from homogeneous batches of olive fruits from Coratina and Frantoio cultivars by using different malaxation times and temperatures. Malaxation time, and especially temperature, negatively affected the intensity of sensory attributes and the content of secoiridoid compounds, modified the composition of metabolites arising from lipoxygenase (LOX) pathways, reducing volatile compounds displaying pleasant sensations and increasing those giving less attractive perceptions, and also elevated the production of 2-methyl butanal and 3-methyl butanal through amino acid conversion. Low temperatures and times, ranging between 30 and 45 min, according to the rheology of the olive pastes, were the optimal operative conditions for the malaxation.     

Assessment of premium organic orange juices authenticity using HPLC-HR-MS and HS-SPME-GC-MS combining data fusion and chemometrics

This study aims to develop a robust chemometric approach to make it possible to authenticate European premium organic orange juices. The metabolomic fingerprinting and the volatile profile of commercial orange juices were analyzed by HPLC-HR-MS and HS-SPME-GC-MS. These data were used for authentication (classification of orange juices) purposes, using principal component analysis, hierarchical cluster analysis and partial least squares discriminant analysis, which provided acceptable results. Some flavonoids, fatty acids, aldehydes and esters were identified as potential markers involved in the differentiation of organic juices. Data fusion strategies were tested and 'mid-level' data fusion achieved an optimal model for classifying organic or conventional orange juices with a sensitivity and specificity of 100%, thus improving the individual models. This approach, combining mass spectrometry techniques, chemometrics and data fusion, likely provides a new framework for the authentication of organic foodstuffs.     

Qualitative and nutraceutical aspects of lemon fruits grown on the mountainsides of the Mount Etna: A first step for a protected designation of origin or protected geographical indication application of the brand name ‘Limone dell'Etna’

The cultivation of lemon (Citrus limon (L.) Burm f.) has occurred for centuries at the mountainsides of the Mount Etna the largest active volcano in Europe (Sicily, Italy). The peculiar geographical, soil and climatic conditions that characterize this area have recently prompted citrus growers to launch the brand name ‘Limone dell'Etna’ for the lemon fruits produced in that area. The present research focused on evaluating the quality and nutraceutical properties of the ‘Limone dell'Etna’ fruit juice (‘Primofiore’, ‘Bianchetto’, and ‘Verdello’ blooming) to enhance the value of a product that, due to its peculiar qualities, could be awarded with one of the European certified labels protecting the lemon geographical origin. Qualitative parameters, health-promoting components (such as ascorbic acid, flavonoids, and hydroxycinnamic acids) and the in-vitro total antioxidant capacity (ORAC, FCR) of fruit juice of two different varieties (‘Femminello zagara bianca’ and ‘Monachello’) were determined at fruit maturity. The results showed that the Bianchetto and Verdello lemon fruit exhibited higher levels of ascorbic acid than those recorded for the Primofiore production. The amount of flavonoids in Verdello fruits of both cultivars was the highest, as was reflected in the highest antioxidant activity. Thus, the ‘Limone dell'Etna’ production, with particular reference to the Verdello fruit, must be considered as a new, valuable and original source of natural antioxidants to be valorized and even exploited in the processing industry.