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Caciotta, M., Giarnetti, S., Orioni, B.
Development of metrology of the organoleptic quality extra virgin olive oil system

In this work, the authors proposed a system of metrology of extra virgin olive oil organoleptic quality, based on Panel Test with specially designed evaluation sheet for the development of the guide "Flos Olei".
The assessment of quality is defined through a holistic processing system based on Kohonen maps, which also provides for the dissemination of metrology system developed by supervised systems of Back Propagation, trained by gas chromatography of oil samples used for the development of metrology.
The making available by E.V.O. editor of "Flos Olei" guide, the evaluation sheets of extra virgin olive oils of the years since 2005, totaling more than 6000 evaluations, allows you to explore them as completely as that to date has ever been done, the distribution of the organoleptic quality.
It is also possible the evaluation of the extension 55 of the flavors explored, on the map, with the relative intensities.
The analysis of the weight coefficients of the Back Propagation of dissemination system, allows to evaluate the sensitivity of the Panel Test flavors identified in the extra virgin olive oil samples taken into account.

Santos, J., Nunes, M. A., Oliveira, M. B. P. P.
Screening of olive pomace polyphenols from individual and mixed olive varieties

Over the last years, olive oil production increased worldwide. Along with this growth, a high rate of residues, namely olive pomace, have been produced. Olive pomace is a natural source of bioactive compounds with major applications for human health and well-being. However, it also has a phytotoxic effect, being an environmental burden. A current sustainable development strategy in Europe agrees, on the context of circular economy, on the recovery of agro by-products and closing the loop between the food production and consumption. Therefore, there is a growing awareness on characterization and identification of natural compounds, as polyphenols, in agro by-products.
This work aimed to compare the phenolic profile of 5 olive pomace samples, 4 from monovarietal pomace and of one composed by a mix of different varieties, all from Portuguese olive oil producers. The freeze- dried olive pomace was submitted to a methanolicultrasound assisted extraction. The total phenolic content was assessed by Folin-Ciocalteu procedure and the phenolic profile by an HPLC-DAD-FL method. The identification of the compounds was made by comparison with standards, when available. The olive pomace phenolic profile was also analysed in an HPLC-DAD-MS n system to tentatively identify the unknown compounds.
The pomace with mixed olive varieties showed the highest phenolic content, followed by samples from monovarietal pomaces. The phenolic profile of all samples showed a high content of hidroxytyrosol, tyrosol and verbascoside. Most of the other compounds found in their profile were derivatives of those compounds and also oleuropein derivatives.

Kalogiouri, N. P., Thomaidis, N. S.
Application of wide scope target, suspect and non-target High Resolution Mass Spectrometric methods coupled with advanced chemometrics in food authenticity studies

Foodomics was defined for the first time in 2009 as “a new discipline that studies the food and nutrition domains through the application of advanced omics technologies to improve consumer’s well-being, health and confidence. Foodomics, more than a simple term covering the panel of the “omic” sciences, also includes the nutritional aspects. Foodomics allows the simultaneous characterization of large numbers of compounds in food matrices, offering to food and nutrition scientists the opportunity to acquire a far more detailed and comprehensive molecular picture of food composition. The concept of authentic, applied to food, certifies that the product is in accordance with standards and regulations. Thus, the development of analytical methods which ensure the authenticity of foods plays a fundamental role in modern society. This can be achieved by the development of analytical methods that apply advanced “omics” technologies to investigate the metabolite profile of different food matrices. High Resolution Mass Spectrometry (HRMS) has been proved to have excellent analytical performance allowing the analysis of a wide range of constituents and assisting identification for both non-target and target compounds. In non- target screening, when there are no reference standards commercially available, the semi-quantification of new compounds remains a challenge. To such an end, chemical similarity analysis can be applied to rank the most appropriate reference standards for semi-quantification purposes. Non-targeted methods combined with chemometrics improve the quality and reliability of the conclusions by suggesting markers. Non-target screening workflows combined with supervised chemometric techniques, such as Partial Least Square – Discriminant Analysis (PLS-DA) and Counter Propagation Artificial Neural Network (CP-ANNs) have been successfully applied for the establishment of classification models that discriminate between defective and EVOOs [4]. Moreover, Ant Colony Optimization Random Forest (ACO-RF/RF) was developed to investigate alterations between organic and conventional EVOOs and introduced one marker with a concentration threshold. HRMS screening workflows coupled to chemometrics reveal the chemical profile (fingerprint) of food products and hence, can be widely applied in food authenticity studies, as complimentary methods. food authenticity, HRMS, EVOO, non-target screening, chemometrics

Abubacker Siddick, S.
Spray drying technology producing tomato powder - Novel way to reduce post harvest loss

Post harvest losses of horticulture farm produce are the major problem in the market supply chain. Loss of food produced is not only waste of food, its waste of small holder’s effort, their inputs, capital and also waste of water resources. Tomatoes are highly perishable with a limited storage life of 7 - 10 days. In India lack of pack house facilities with infrastructure for sorting, grading, cold chain logistics and post harvest processing mechanism, the farmers are getting very low returns with loads of marketable surplus left behind. In Tamil Nadu tomato crop is cultivated on more than 28,000 Ha with average production of 3.25 thousand tonnes per year.
Tomato is the major vegetable crop cultivated in Dindigul district on an area of more than 2200 Ha across 5 major taluks with a tremendous potential of post harvest processing. Spray drying is one of the innovative post harvest technology for making fruit powders. A study was conducted in Gandhigram with locally available tomato varieties and hybrids using commercial scale ACMEFIL spray dryer with Public- Private- Partnership mode. Tomato growers from Oddanchatram, Dindigul, Reddiyar chatram, and Ayyalur with known varieties of tomatoes like Ruchi Hybrid, Annangi (Nadu), Co-3, and PKM-1 in link with Aruna agro agencies, Theni (Buyer) and Gandhigram Rural Institute (Technology provider) supplied fresh tomatoes.
The spray drying behaviour of different tomato juice at various inlet and outlet temperatures was studied with continuous observation of parameters like feed flow rate, addition of malt dextrin and powder yield. With addition of 8% malt dextrin and a feed rate of 80 ml per minute controlled by the peristaltic pump, inlet temperature as 160 °C and an outlet temp of 90 °C was observed as optimum conditions for high recovery of fruit powders. The physical, chemical and biological properties of spray dried powders of tomato varieties are recorded.

Gueifão, S., Sanches, D., Delgado, I., Coelho, I., Ventura M., Castanheira, I.
Abundance of selenium and selenoproteins in foods consumed in Portugal

Selenium (Se) is an essential element for human health. Dietary levels in the population are positively correlated to selenium content in foods as consumed. Dietary Reference Intake for Se is 55 µg/day for adult men and women. However, depending on the species, oxidation state and concentration Se can be toxic to human health. Accurate determination of Se content in the diet demands information not only on total Se (tSe) but also on the bioaccessible species presented in food samples.
The aim of this work was to evaluate the concentration of tSe and Se species as Selenomethionine (SeMet), Selenite (SeIV) and Selenate (SeVI) in cow milk, cabbage and fish samples consumed in Portugal.
Accurate analysis of tSe was carried out by ICP-MS preceded by acid digestion in a closed-vessel microwave system. Several approaches for extraction of Se species from food matrices were studied followed by quantification with HPLC-ICP-MS. The reliable conditions of analytical procedures were achieved with metrological tools operated under the frame of ISO/EN 17025:2005.
tSe content ranged from 67 ± 3 ug.kg-1 (cabbage), 161 ± 16 ug.kg-1 (milk) and 988 ± 27 ug.kg-1 (fish). SeMet was major selenium species in milk and fish samples accounting for 85 -90 % of tSe content. In cabbage Se (IV), Se (VI) and (SeMet) were found.
The results showed the suitability of analytical procedure to measure tSe and seemed effective to achieve an accurate determination of Se species in these complex matrices.

Arık Kibar, E. A., Us, F.
Starch - Cellulose ether films: Microstructure and water resistance

In this study, composite films of corn starch, methylcellulose and carboxymethylcellulose plasticized by glycerol or polyethylene glycol (PEG) were prepared and the effects of blending level as well as the plasticizer type on the microstructure, water vapour permeability (WVP), opacity and solubility properties were investigated. SEM observations showed homogeneous matrix of glycerol plasticized films and it was taken as an indicator of structural integrity. PEG plasticized films exhibited discontinuous surface, and this was attributed to phase separation.

Pedrotti, M., Khomenko. I., Cappellin, L., Fogliano, V., Biasioli, F.
Implementation of rapid and non-invasive quality control through PTR-ToF-MS for anhydrous milk fat quality control

In this pilot study, Proton Transfer Reaction Mass Spectrometry coupled with a time- of-flight mass analyzer and an automatic sampler was evaluated as rapid a rapid tool for the quality control of anhydrous milk fat. Two different types of packaging for storage – cardboard and bag-in- box - were evaluated during accelerated shelf life at 50°C for 11 days.
Preliminary results show the possibility to identify markers related to both products packaging and shelf life, thus indicating the possible application of Proton Transfer Reaction Mass Spectrometry in agroindustry quality control programs.

Shi, J.
Multicore-microencapsulation of bioactive-rich extracts, an innovative technology for functional food ingredients

Multicore-delivery of bioactive mixture through microencapsulation has several advantages over the intake of single component in the formulation, in which there is a synergistic antioxidant effect among different bioactives. Fruit pomace extract contains both hydrophobic and hydrophilic components. Studies are taking critical approach to develop unique multicore microencapsulation with fruit pomace extract and other natural bioactives to promote high synergistic effects and enhance bioactivity and bioavailability. Study is to develop microcapsules by double emulsion (w/o/w) and complex coacervation technology. The optimum proteins-polysaccharides shell model is to select food-grade proteins and polysaccharides pair to protect efficiently bioactives in core against oxidation and degradation. The optimum shell model has high potential to increase their bioavailability of the fruit pomace extract, and control the rate of bioactive release to reach the intended destinatioN·multicore microencapsulation can be considered as unique emerging technology to develop new generation of functional food ingredients, in which the multicore formulation of fruit pomace extract can promote high synergistic antioxidant effects. Multicore microencapsulation can effectively enhance bioactivity, protect against oxidation, and mask their odor and bitter taste, promote high bioavailability. The multicore microencapsulation will pave the way for the development of phytochemical-rich extract as natural functional food ingredients from many other by- product extracts. Multicore microencapsulation technology and process facilitate bioactive mixture extracted from agricultural by-products to convert into value-added health-promoting food ingredients with high bioactivity, stability and bioavailability.

Diretto, G., Sulli, M., Demurtas, O., Frusciante, S., Giuliano, G.
Environmental and processing-derived metabolomics alterations in saffron (C. sativus L.) mature stigmas from two PDO ecotypes (Castilla-La Mancha; Kozani)

Saffron is the most expensive spice in the world, mainly due to its very limited and costly production, both in terms of product amount (3 stigmas for 3 flowers are produced from each corm) and cultivation, and of manual procedures of harvest, respectively. For all these aspects, saffron is one of the most adulterated and sophisticated product on the market, and assessment of robust protocols of metabolite determination, with the subsequent determination of genotype- or process-specific metabolic markers are needed to assist the consumers. Europe owes several high-quality ecotypes, as the Spanish “Castilla-La Mancha” and the Greek “Krocus Kozanis”, which are subjected to distinct methods of dessication, and that were utilized in the present study to develop a saffron-specific metabolomics database. At this aim, global metabolic profiling protocols were set up for both polar and non polar fractionby high resolution (Orbitrap) LC-ESI(+)- MS and LC-APCI(+)-MS. Overall, a custom database of saffron polar and non polar metabolites was constructed, by combining metabolite lists developed “in house” on different matrices, data from the literature, and identification of the main chromatographic peaks on the basis of thei accurate mass, by online database (Metlin, Chemspider) interrogation. A large set of primary and secondary metabolites, including amino acids, organic acids, sugars, lipids, apocarotenoids, phenolics, flavonoids, carotenoids, isoprenoids etc was identified, and a series of bioinformatics approaches including multivariate (PCA), hierarchical clustering (HCL) and correlation matrices and networks were exploited to identify metabolic markers specifically associated to the two PDO ecotypes under study.

Vlachou, C., Hatzi, E., Xonoglou, N., Liouza, D., Tarantili, P.
Chemical analysis and chemometrics for Greek potable waters classification

Mineral, spring and tap water samples from Greece have been analysed. Analytical measurements were performed for a number of parameters: pH, conductivity, cations (Na+, NH4+, Mg2+, Ca2+, K+) and anions (Cl-, F-, NO2-, NO3-, Br-, PO43-, SO42-), by ion chromatography, and heavy metals (Ba, B, Cd, Mn, Pb, Ni, Fe, Cu, Cr by Graphite Furnace Atomic Absorption Spectroscopy and As, Hg, Sb, Se by Flow Injection Atomic Spectroscopy).
A chemometrics tool, namely LDA (Linear Discriminant Analysis) has been applied on the analytical results for the discrimination of the samples of different category and geographic origin. The purpose of this methodology was to detect the possible relationship between physical properties, chemical composition and water sampling area and to define the critical parameters for distinct characterization of individual water categories. This classification will allow the surveillance of water quality in the future and early detection of possible contamination originating from anthropogenic activities (industry, agriculture, other) or deterioration originating from water supply networks.

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