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Evolution of the volatile profile of two extra-virgin olive oils with very different fatty acid composition (monounsaturated fatty acid/polyunsaturated fatty acid ratio) stored in several nonaccelerated oxidative conditions was studied by a validated headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method. The role of C8 volatile compounds in oxidative processes was highlighted, and controversial aspects regarding the origin of some volatiles were clarified. Specific volatile markers for rancidity were proposed: sum of pentanal, hexanal, nonanal, E-2-heptenal, propanoic acid, and hexanoic acid for oils stored in the dark; sum of pentanal, heptanal, nonanal, decanal, E-2-heptenal, E-2-decenal, E,E-hepta-2,4-dienal, and E,E-deca-2,4-dienal, octane for oils stored under light exposure; sum of pentanal, nonanal, decanal, E-2-heptenal, E-2-decenal, E,E-hepta-2,4-dienal, nonan-1-ol, propanoic acid, octane, 6-methylhept-5-en-2-one, and oct-1-en-3-ol for oils stored under light exposure with oxygen in headspace. A simplified marker (sum of pentanal, nonanal and E-2-heptenal) suitable for all conditions was also proposed.

A reliable and robust tool for supporting the panel test in virgin olive oil classification is still required. We propose four chemometric approaches based on t test, principal component analysis (PCA) and linear discriminant analysis (LDA), applied for combining sensorial data, and chemical measurements. The former was from the panel test, and the latter was from headspace solid-phase microextraction-gas chromatography-mass spectrometry quantitation of 73 volatile organic compounds (VOCs) of 1223 typical commercial virgin olive oils, with most of them recognized as difficult to classify with accuracy by the panel test. The approaches were developed and validated, and the best results, with 83.5% correct classification, were using the PCA-LDA approach. Among the other methods, developed for proposing simplified procedures based on a smaller number of VOCs, the best method gave 80.1% correct classification only using 10 VOCs. All of the approaches suggested that octane, heptanal, pent-1-en-3-ol, Z-3-hexenal, nonanal, and 4-ethylphenol should be considered as a basis of volatiles for classification of olive oil samples.

Volatile organic compounds strongly contribute to both the positive and negative sensory attributes of virgin olive oil, and more and more studies have been published in recent years focusing on several aspects regarding these molecules. This Review is aimed at giving an overview on the state of the art about the virgin olive oil volatile compounds. Particular emphasis was given to the composition of the volatile fraction, the analytical issues and approaches for analysis, the sensory characteristics and interaction with phenolic compounds, and the approaches for supporting the Panel Test in virgin olive oil classification and in authentication of the botanical and geographic origin based on volatile compounds. A pair of detailed tables with a total of approximately 700 volatiles identified or tentatively identified to date and tables dealing with analytical procedures, sensory characteristics of volatiles, and specific chemometric approaches for quality assessment are also provided.

Several studies demonstrate a strong interest in learning more about phenolic transfer during oil extraction, with the main goal of increasing the phenolic concentration in olive oils. We aimed to propose and apply a new methodological approach for evaluating phenolic transfer from olives into oil during milling, based on the quantification of phenolic content in whole lyophilized fruits and the corresponding oils and considering the oil extraction yields.; Results: We investigated the phenols transferred into the oil during olive milling in continuous extraction systems in Tuscany. In 2012, oils were extracted from cultivar Frantoio by a two-phase extraction system; in 2016, oils were extracted from cultivars Leccio del Corno and Arbequina by a three-phase extraction system. Results highlighted very low percentages of extracted phenols: up to 0.40% by the two-phase system and up to 0.19% by the three-phase system (0.08% for cultivar Arbequina and 0.19% for cultivar Leccio del Corno).; Conclusion: The usefulness of a simple and effective methodological approach for evaluating the extracted phenols was highlighted. Values of extracted phenols were up to 25 times lower than previous literature data. The proposed approach is applicable in all types of milling processes. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Herein we describe the influence of olive oil refining processes on the lignan profile. The detection of new isobaric lignans is suggested to reveal frauds in commercial extra-Virgin Olive Oils. We analyzed five commercial olive oils by HPLC-DAD-TOF/MS to evaluate their lignan content and detected, for the first time, some isobaric forms of natural (+)-pinoresinol and (+)-1-acetoxypinoresinol. Then we analyzed partially and fully-refined oils from Italy, Tunisia and Spain. The isobaric forms occur only during the bleaching step of the refining process and remain unaltered after the final deodorizing step. Molecular dynamic simulation helped to identify the most probable chemical structures corresponding to these new isobars with data in agreement with the chromatographic findings. The total lignan amounts in commercial olive oils was close to 2mg/L. Detection of these new lignans can be used as marker of undeclared refining procedures in commercial extra-virgin and/or Virgin Olive Oils.

Authentication of geographical origin of virgin olive oils is necessary to protect consumer and producers from frauds. A method able to classify virgin olive oils from the main worldwide producing countries is still missing. In this work, we developed 3 chemometric approaches for classification of virgin olive oils from Italy, Spain, Greece, Portugal, Tunisia and other countries all over the world. The approaches were developed starting from a data-set containing fatty acid composition and the amount of 72 volatile compounds, evaluated by a never applied HS-SPME-GC-MS quantitation method, of 1217 oil samples from three different olive oil campaign. The approach that gave the best predictive results is based on Linear Discriminant Analysis run on quantitative data from only 25 volatile compounds selected by one-way ANOVA as the most capable in discriminating between the diverse origins. The method was built and internally validated using a training-set of 1000 samples and externally validated with a test-set of 217 independent samples. The method was able to classify the geographical origin of 94.5% samples, with a percentage of correct classification even higher than 97% for some origins. Preliminary studies also suggested the proposed approach is able to correctly classify the geographical origin of binary mixtures of oils from different origins. The approach proposed in this manuscript is easily applicable in testing laboratories and represents a very useful tool for the olive oil field, helping in protecting consumers and producers from frauds.

This study evaluates the effect of filter press filtration on the shelf life of extra virgin olive oil (EVOO). Olives were harvested and processed on the same day by a continuous industrial plant equipped with a hammer crusher, a vertical malaxator, and a decanter. One part of the oil obtained was bottled in 0.5 liter dark‐green bottles with headspace representing a quarter of the bottle's volume (cloudy oil). The other part was filtered (using a filter press) directly after decanting and manually bottled using the same procedure (filtered oil). All samples were stored in a purpose‐built chamber and periodically analyzed. Samples were characterized by their water content, free acidity, peroxide value, specific extinction coefficients (K232 and K268), total chlorophyll, tocopherols, total phenolic compounds, HPLC phenolic profile, volatile compounds, fatty acid composition, and sensory analysis. Immediately after filtration, the only differences that could be detected were related to turbidity and total solids. In the subsequent analyses, filtered oil retained superior nutritional and sensory characteristics than cloudy oil. More importantly, the filtered oil remained at the standard required for categorization as “extra‐virgin olive oil” for longer. Practical applications: The article describes the effect of the filtration without vertical centrifugation on the olive oil quality. Shelf life tests have been performed to evaluate the changes in chemical and sensorial properties of olive oils. Since the filtration and its timing is controversial in the literature, a complete investigation, which considers the storage, is required. Furthermore, this is, to the best of authors knowledge, the first study focusing on the changes of oils produced without vertical centrifuge. This study evaluates the effect of filter press filtration on the shelf life of extra virgin olive oil (EVOO). Olives were harvested and processed on the same day by a continuous industrial plant equipped with a hammer crusher, a vertical malaxator, and a decanter. One part of the oil obtained was bottled (cloudy oil). The other part was filtered (using a filter press) directly after decanting and manually bottled using the same procedure (filtered oil). All samples were stored in a purpose‐built chamber and periodically analyzed. The results show a less degraded phenolic fraction in the filtered olive oils. In fact, compounds such as Tyrosol and Hydroxytyrosol, which are the final product of hydrolysis of secoiridoids, remain stable in filtered oils and increase in cloudy. Moreover, filtered olive oils have a better sensory profile than the cloudy along the shelf life. These data are confirmed by the GC‐MS analysis. The results confirm that filtration is essential in order to maintain the nutritional characteristics of the oil, and slow the onset of the main defects.

Several studies demonstrate a strong interest in learning more about phenolic transfer during oil extraction, with the main goal of increasing the phenolic concentration in olive oils. We aimed to propose and apply a new methodological approach for evaluating phenolic transfer from olives into oil during milling, based on the quantification of phenolic content in whole lyophilized fruits and the corresponding oils and considering the oil extraction yields.We investigated the phenols transferred into the oil during olive milling in continuous extraction systems in Tuscany. In 2012, oils were extracted from cultivar Frantoio by a two-phase extraction system; in 2016, oils were extracted from cultivars Leccio del Corno and Arbequina by a three-phase extraction system. Results highlighted very low percentages of extracted phenols: up to 0.40% by the two-phase system and up to 0.19% by the three-phase system (0.08% for cultivar Arbequina and 0.19% for cultivar Leccio del Corno).The usefulness of a simple and effective methodological approach for evaluating the extracted phenols was highlighted. Values of extracted phenols were up to 25 times lower than previous literature data. The proposed approach is applicable in all types of milling processes. © 2017 Society of Chemical Industry.

This work deals with the evolution of the phenolic profile in olive fruits of three typical Tuscan cultivars, Frantoio, Moraiolo and Leccino, during the ripening period (September and end of November). The main goals were to study the possible relationships between phenol, total sugar and oil contents in the fruit to determine the best harvesting time for oil production. The analysis by HPLC/DAD/ESI/MS enabled the assessment of the evolution during ripening for 20 different phenolic compounds. The presence of lignans and dialdehydic form of decarboxymethyl oleuropein aglycone (3,4-DHPEA-EDA) was excluded in all these fruits. In terms of total phenols, Moraiolo was always the richest cultivar with concentrations ranging between 12.1 and 21.3 g kg− 1; the phenolic reduction was scarcely appreciable in Frantoio, while for Moraiolo and Leccino the decrease was almost inversely related to the ripening time. For every cultivar the oleuropein trend was compared with the sugar and oil contents over time. By the statistical evaluation (correlation coefficient approach) inverse relations between the sugar amount and the oil content and significant relations between two minor phenols (chlorogenic acid, tyrosol) and the oil amount have been highlighted for each cv.

Crushing speed can be used to characterize olive oils. Faster crushing significantly increases chlorophyll, total biophenol, 3,4‐DHPEA‐EDA, and p‐DHPEA‐EDA. Panel testing found higher bitterness and astringency scores in oils produced at the higher speed.

In olive oil production, olive paste is fed into a decanter in order to separate the oil from solids. The decanter is usually fed by a mohno or lobe pump. In this study, we analyze the composition of olive paste and pomace at the beginning, middle, and end of decanter feeding. The results show a change in paste composition with the two types of pumps. In both cases, olive paste contains a higher percentage of water and oil at the beginning of decanter feeding than at the end. This phenomenon is probably related to the different viscosity of the three components in the system. Furthermore, as the level for the recovery of olive oil is fixed, the change in the solid/liquid ratio causes product loss. This loss is demonstrated and quantified through the measurement of pomace oil content. Practical Applications: The paper quantifies the effect of the olive paste transport from malaxers to decanter on the olive oil yield. The transport causes a change in the relative composition among oil, water, and solids. The decanter centrifuge is not able to separate efficiently paste with different compositions. This causes marked product losses. The presented data could lead to the development of a control system able to limit the losses. In this study the ratio of solids, water and oil in the olive paste at the beginning, middle, and end of decanter feeding are tested. Change in paste composition with the two types of pumps. Olive paste contains a higher percentage of water and oil at the beginning of decanter feeding than at the end. The level for the recovery of oil is fixed and the change in the ratio causes product loss that is quantified through the measurement of pomace oil content.

The commercial value of virgin olive oils (VOOs) strongly depends on their classification, also based on the aroma of the oils, usually evaluated by a panel test. Nowadays, a reliable analytical method is still needed to evaluate the volatile organic compounds (VOCs) and support the standard panel test method. To date, the use of HS-SPME sampling coupled to GC-MS is generally accepted for the analysis of VOCs in VOOs. However, VOO is a challenging matrix due to the simultaneous presence of: i) compounds at ppm and ppb concentrations; ii) molecules belonging to different chemical classes and iii) analytes with a wide range of molecular mass. Therefore, HS-SPME-GC-MS quantitation based upon the use of external standard method or of only a single internal standard (ISTD) for data normalization in an internal standard method, may be troublesome. In this work a multiple internal standard normalization is proposed to overcome these problems and improving quantitation of VOO-VOCs. As many as 11 ISTDs were used for quantitation of 71 VOCs. For each of them the most suitable ISTD was selected and a good linearity in a wide range of calibration was obtained. Except for E-2-hexenal, without ISTD or with an unsuitable ISTD, the linear range of calibration was narrower with respect to that obtained by a suitable ISTD, confirming the usefulness of multiple internal standard normalization for the correct quantitation of VOCs profile in VOOs. The method was validated for 71 VOCs, and then applied to a series of lampante virgin olive oils and extra virgin olive oils. In light of our results, we propose the application of this analytical approach for routine quantitative analyses and to support sensorial analysis for the evaluation of positive and negative VOOs attributes.

The aim of this work was to study, under different conditions, degradation of secoiridoids during extraction of extra virgin olive oil by following the effect of ascorbic and citric acid addition. Their effect was evaluated on oil obtained from both damaged olives and undamaged fresh olives. Addition of enzyme inhibitors to damaged olives during olive milling allowed us to obtain oil with a higher phenolic compound content. Conversely, addition of the same inhibitors to undamaged fresh olives, during oil milling, resulted in no significant improvement in the phenolic compound content of oil. A high presence of PPO was thus indirectly confirmed, as damaged olives were only found to be sensitive to action of inhibitors. Ascorbic acid was found to be more effective than citric acid in preserving phenolic compounds of oil. Trials on undamaged fresh olives confirmed occurrence of hydrolytic transformation phenomena for secoiridoids during extra virgin olive oil production process. In particular, the quantitatively most representative component for Frantoio cultivar was found to be 3,4-DHPEA-EDA. This compound may be considered a direct marker for the degree of transformation of secoiridoids during production process. Practical applications: The processing of undamaged olives resulted in the extraction of extra virgin olive oil with a higher phenol content. It could be indirectly inferred that a reduced activity of PPO caused a low secoiridoid degradation both before and after malaxation. Lightly scratched, overripe olives could be used in those markets where the addition of oxidation-inhibiting substances is allowed. Using inhibitors can be suggested for olive washing step.

The quality changes in extra virgin olive oil afforded by the conservation in bottles of different materials were assessed in a 12-month shelf-life test. Transparent clear glass (TCG), green coloured glass (CG) and stainless steel (SS) 250-ml bottles were studied (in triplicates) alternating natural and fluorescent light to simulate the ‘in the drugstore’ conditions. Every 2 months, the quality decay was assessed by monitoring some chemicals parameters and by sensory evaluation. Principal component analysis evidenced a clustering of the samples as a function of storage time and bottle type. The SS bottles showed the best storage performances, whereas only minor differences were detected in TCG and CG. A large variability was detected within the replicated glass bottles, probably as a consequence of some uncontrolled variations in the light exposure. This was confirmed by the measure of light intensity over the storing surface, which showed a large variability (15%) around an average value of 380 lux. Under light exposure, a limited antioxidant effect of phenolic compounds was recorded. Only some specific phenols seem to play an important role in oil protection against oxidation. Copyright © 2010 John Wiley & Sons, Ltd.

"Marrone del Mugello" PGI (PGI=Protected Geographical Indication) is a quality trademark recognized by the European Community with regulation n. 1263/96 for fruits (fresh, dried or milled as flour) and obtained from European Chestnut Trees (Castanea sativa Mill.) growing in the Mugello area (Tuscany-Italy). The chestnut fruit has a particular chemical composition, very rich in carbohydrates and in starch, that decrease during the post harvest period. In the Mugello area (Tuscany-Italy) is diffused a traditional post-harvest methodology that belong to the past: the "water curing", that extends the preservation of these fruits up to four months. In fact "water curing" was known in the past as "novena" which means that fresh chestnut fruits were kept for nine days in the water to extend their shelf life. The objective of this method is to reduce the development of fungi during the storage processes and at the same time to promote the death of worms living in the chestnut fruits. This paper reports some preliminary results of some tests carried out during this treatment to verify its ability to preserve the nutritional values of chestnut fruits. Effects of "water curing" on the fungi development were observed.

BACKGROUND: The aim of this work was to study the evolution of sugar and oil contents in Frantoio cultivar olives during ripening in order to propose a technological ripening index for olive oil fruits. Olive fruits were picked at nine different farms once a week from the beginning of September to the beginning of December during three crop seasons. RESULTS: As a result of the biochemical phenomenon of oil formation in olive fruits, sugar concentration during ripening was shown to follow a sigmoidal decrease, which recurred periodically in different microclimates over years. This trend resulted to be the cause of an opposite sigmoidal increase in oil content. Experimental data for sugar and oil contents were also statistically related by significant linear relationships. In addition, it was observed that reaching a minimum environmental temperature of ⩽10 °C resulted in a definite minimum asymptotic value for sugars. CONCLUSION: Sugar concentration can be proposed as an accurate, reproducible index for technological ripening of olive oil fruits by the following prediction function: proper ripening degree of olives corresponds to achievement of a constant minimum value for sugar content and, consequently, a constant maximum value for oil content, associated with reduced risk of fermentation activities of olive paste. Copyright © 2009 Society of Chemical Industry

European chestnut has been cultivated in the Mugello territory (Tuscany) since the period of the Roman Empire. Marrone del Mugello chestnut was awarded PGI recognition (Protected Geographical Indication) for its typical natural and biological characteristics with EC Regulation n.1263/96. This paper reports the main results obtained after four years of evaluation of several samples of Marrone del Mugello PGI collected in the area of the Protected Geographical Indication, by means of chemical and sensorial tests and taking into account the complexity of compounds. The analysed samples included fresh nuts, fresh cured nuts, dried nuts and flour. Curing is a preservation process that consists in pouring chestnuts in water for almost seven days. The drying process is done according to the traditional method in special drying-houses ("metati") and takes about 40 days by warming up to 35-40°C the chestnuts. The dried nut is separated mechanically from shell and episperm and it could then be marketed as whole dried nut or milled to obtain flour. Macronutrients, microelements, vitamins and antioxidants (especially biophenols and tocopherols) were chemically analysed to underline the nutritional qualities of the fruit. Chemical analysis reveals high nutritional value and healthy compounds, justifying Marrone del Mugello PGI as part of the Mediterranean diet. Sensory analysis, with a specific Panel Test by trained assessors, provides a qualitative and quantitative characterization of Marrone del Mugello PGI taste and flavour. A preliminary investigation of the aroma compounds of chestnut flour was also carried out using an HS-SPME/GC-MS method.

A flow injection system with amperometric de- tection at potentials poised at + 0.4 and + 0.9 V was used to evaluate intensity of the bitter taste in monovarietal Extra Virgin Olive Oils (EVOO). Results from the pro- posed method were based on the extraction of the bitter constituents of the virgin olive oil samples in methanol- water, followed by the direct amperometric measurement. These potentials were selected according to the hydrody- namic voltammogram of oleuropein, one of the most prominent and bitter phenolic compound found in EVOO. The amperometric detection was applied on 32 monovariatal EVOO samples. Results were correlated with the phenolic profile measured by high performance liquid chromatography (HPLC). The amperometric signal at + 0.9 V mainly correlated with the total phenols of the samples (R2 = 0.81), whereas the signal at + 0.4 V mainly correlated with oleuropein aglycone (3,4 DHPEA-EDA, R2 = 0.79). Bitterness intensity of the samples was evalu- ated by a trained sensory panel of experts and the results compared to those obtained by the amperometric flow system. The best correlation with the bitter taste was ach- ieved by the sensor at + 0.4 V (R2 = 0.72). A calibration model based on partial least squares was built with three variables, namely the sensors set at + 0.4 and + 0.9 V and the total phenol content of the EVOO extracts. The model showed a moderate capacity to predict the bitter- ness of the EVOO samples using leave one out method, (R2 = 0.75) and in prediction of a test set of samples (R2 = 0.7). Such approach is very promising for future studies.

The aim of this work was to investigate the effect of malaxation operating conditions on virgin olive oil quality. Legal, sensory and nutritional parameters of olive oil were evaluated by identifying the role played by enzymes. A comparison was made between oil obtained from a traditional malaxation plant and oil obtained from malaxation equipment (LOM) able to work at low oxygen level and temperature. Research results showed that, during malaxation, oxygen had an effect on both phenolic compounds and fatty acids, mainly favouring enzyme phenomena. Malaxation at a low oxygen level was found to be selective for the formation of both phenolic and C6 compounds. Oil obtained from malaxation LOM equipment was shown to be richer in both aldehydes such as trans-2-hexenal and phenolic compounds than oil obtained from traditional processing. Copyright © 2006 Society of Chemical Industry

The phenolic profiles of three typical Tuscan olive cultivars, Frantoio, Moraiolo, and Leccino, stored in different conditions (fresh, frozen, and whole lyophilized fruits), have been compared during the ripening period. Our main goals were to evaluate the phenolic content of whole freeze-dried fruits and to test the stability of the corresponding cake in oxidative-stress conditions. The comparison of fresh and whole freeze-dried fruits from the 2012 season gave unexpected results; e.g., oleuropein in lyophilized fruits was up to 20 times higher than in fresh olives with values up to 80.3 g/kg. Over time we noted that the olive pastes obtained from lyophilized olives contained highly stable phenolic compounds, even under strong oxidative stress conditions. Finally, it was also observed that the cake/powder obtained from unripe freeze-dried olives was very poor in oil content and therefore quite suitable for use in nutritional supplements rich in phenolic compounds, such as secoiridoids, which are not widely present in the human diet.

Olive oil is a turbid colloidal dispersion. The most common technique used to clear the oil is filtration. Among filter systems, plate filter-presses are used by small companies because the filters are cheap, and the technique does not impair the sensory and chemical traits of the olive oil. However, plate filter-presses have some disadvantages: their operating capacity is low, they require a lot of man power, and filter sheets trap part of the processed oil. It has been argued in the literature that they can retain minor compounds. Furthermore, there is a cost associated with their disposal. The impact of all of these issues could be reduced by the optimization of filtration cycles. Hence, a new processing arrangement was proposed and tested. This consisted of the insertion of a steel pre-filter into the system, which retained part of the suspension. Consequently, the plate filter-press only retained residual solids and water. The plate filter press with the added pre-filter was able to process about 1.8 times the amount of oil normally processed in a batch. Operative capacity was improved and the amount of oil trapped in the sheets was reduced. Furthermore, the number of the filter sheets required was almost halved, which also halves their purchase and disposal costs. A surface fouling mechanism is seen in the traditional filter press configuration, while in the new configuration particle retention is due to depth fouling. This change in the fouling mechanism demonstrates that the addition of a pre-filtration step leads to the more effective use of filter sheets.

In our previous work ( Cherubini et al., 2009 ), sugar concentration was proposed as an accurate, reproducible index for technological ripening of olive oil fruits. During 2009 crop season, sugar and oil content of olive oil fruits from Moraiolo and Leccino cultivars were measured during ripening. The sugar content of olive oil fruits was determined both by titration and by using a portable refractometer. A linear relationship was found, which was similar to that identified for Frantoio cultivar in our previous work. Evaluation of °Brix using a refractometer was found to be linearly correlated to the sugar content of olive oil fruits. It was confirmed that sugar concentration may be considered as a direct index for peculiar biochemical phenomenon of oil accumulation during ripening of olive oil fruits. Evaluation of °Brix could thus be useful for a simple, fast determination of the sugar content and, indirectly, the relevant oil content.

The extraction procedures (solid/liquid SPE and liquid/liquid LLE) and HPLC separation and quantification methods of polyphenolic compounds have been checked in virgin olive oils in order to explain the differences in content reported in the literature. The work has been carried out on oils prepared from one cultivar and produced under the same protocol. The extraction methods are practically equivalent, but the SPE technique is more favorable because it is faster and simpler. It has been proved that the chromatographic features and the method of chemical expression of the concentrations may greatly affect the final values. Thus, under the same analytical method, the total concentration values of polyphenols of the same oil show variations from 18% to 80%, according to the formality of expression as gallic acid, caffeic acid, or tyrosol equivalents. The role of the nature and spectrophotometric features of the phenols and of the internal standard is also discussed, and it was found to be an important source of reported variation. A gradient separation with an eluent mixture acetonitrile-sulfuric acid (0.1 mol/L), detection at 225 nm, and quantitative calculation of polyphenolic compounds in oils (expressed as tyrosol equivalents, THY(eq)) is proposed.

The new compounds 1,4,10,13-tetrakis(2,3-dihydroxybenzoyl)-7,16-dimethyl-1,4,7,10,13,16-hexaazacyclooctadecane (H8L1) and 1,4,7,10,13,16-hexakis(2,3-dihydroxybenzoyl)-1,4,7,10,13,16-hexaazacyclooctadecane (H12L2), having macrocyclic skeletons bearing four and six catechol hanging groups, respectively, have been synthesized and characterised. The crystal structure of H8L1·2dmso·2H2O (dmso = dimethyl sulfoxide), has been solved by single-crystal X-ray analysis. The equilibrium constants for protonation of the macrocycles and complexation of Fe3+ have been studied by potentiometric procedures in water–dmso (50∶50 v/v), 0.1 mol dm–3 NMe4Cl, at 298.1 ± 0.1 K. Both compounds are able to form mono- and di-nuclear iron(III) complexes of very high stability. These results indicate that the two compounds are thermodynamically able to scavenge Fe3+ from iron(III) transferrin. Their effectiveness as scavengers has been demonstrated by spectrophotometric measurements on the transmetallation reactions occurring in the presence of diiron(III) transferrin in aqueous solution. For comparison, the drug desferrioxamine B (DFB) has been also considered under the same experimental conditions. In 0.1 mol dm–3 phosphate buffer, at pH 7.4, both H8L1 and H12L2 remove iron from diiron(III) transferrin, the transmetallation reactions being much faster for H12L2 than for DFB which is slightly more effective than H8L1.

Plants contain a wide range of non-nutritive phytochemicals, many of which have protective or preventive properties for human diseases. The aim of the present work has been to investigate the nutraceutical properties of sweet chestnut flour extracts obtained from fruits collected from 7 geographic areas of Tuscany (Italy), and their ability in modulating skeletal muscle atrophy. We found that the cultivars from different geographic areas are characterized by the composition and quantity of various nutrients and specific bioactive components, such as tocopherols, polyphenols and sphingolipids. The nutraceutical properties of chestnut sweet flours have been evaluated in C2C12 myotubes induced to atrophy by serum deprivation or dexamethasone. We found that the pretreatment with both total extracts of tocopherols and sphingolipids is able to counterbalance cell atrophy, reducing the decrease in myotube size and myonuclei number, and attenuating protein degradation and the increase in expression of MAFbx/atrogin-1 (a muscle-specific atrophy marker). By contrast, polyphenol extracts were not able to prevent atrophy. Since we also found that γ-tocopherol is the major form of tocopherol in sweet flour and its content differs depending on the procedure of sweet flour preparation, the mechanisms by which γ-tocopherol as well as sphingolipids affect skeletal muscle cell atrophy have been also investigated. This is the first evidence that chestnut sweet flour is a natural source of specific bioactive components with a relevant role in the prevention of cell degeneration and maintenance of skeletal muscle mass, opening important implications in designing appropriate nutritional therapeutic approaches to skeletal muscle atrophy.

The aim of this work was to apply and validate a NIR spectrometer based on a discrete filter system for the rapid measurement of the moisture, oil, sugar and phenolic compounds contents of olive oil fruits. The batches of olive oil fruits were collected during seven crop seasons from several farms located in Tuscany and then they were crushed into olive paste. The water content was measured gravimetrically, oil content was measured using the Soxhlet method, sugar content was measured enzymatically and phenolic compound content was measured by HPLC. NIR spectra were recorded from 1400 to 2400 nm at 19 selected wavelengths. Calibration and validation models were processed using PLS regression. In PLS models built for moisture, oil and sugar contents, the r2 in calibration ranged between 0.90 and 0.93 with low SEC values (i.e. 2.5, 3.6 and 4.0, respectively). For these parameters the SEP and the SEL values proved to be comparable (i.e. 2.4 vs 3.2, 6.0 vs 4.4 and 6.7 vs 4.7, respectively). Instead, the calibration and validation results concerning the phenolic compounds were not satisfactory, probably because the necessary wavelengths in the section of absorbance from 1100 to 1400 nm were not covered. Practical applications: NIR spectrometers based on discrete filter systems may be interesting since they are cost-saving compared to the more sophisticated FT-NIR and NIR-AOTF instruments (i.e. the cost is approximately half). Our study also showed that with this instrument it was possible to build some effective models for predicting moisture, oil and sugar contents in olive paste. The results obtained for moisture and oil contents are comparable with those obtained with other spectrometers, and a predictive model was obtained for sugar content for the first time. Instead the tool did not prove suitable for obtaining predictive models for total phenolic compounds or oleuropein contents. The additional use of a filter-based NIR spectrometer is therefore to be suggested to rapidly monitor olive fruit ripening on the basis of moisture, oil and sugar contents.

Olive oil quality is strictly correlated to the volatile compounds profile. Both quality and defects can be connected to the presence of specific volatile compounds in the oil headspace. In this paper, olive oil samples have been artificially modified by adding a number of compounds known to be typical of the more frequent defects: fusty, musty, muddy and rancid. Results demonstrate the sensitivity of the electronic nose to the compounds characterizing the defects and then the capability of the instrument to identify the defects in real samples.