Use of sieving as a valuable technology to produce enriched buckwheat flours: A preliminary study

Fractionation processes based on physical separation are a good strategy to produce enriched cereal flours. Therefore, the aim of this work is to evaluate the suitability of sieving of buckwheat flours to produce protein and phenolic (especially rutin) enriched fractions. Because of that, dehulled whole buckwheat flour (GSTQ) was sieved obtaining fractions with a particle size of 215 \uf06dm, 160 \uf06dm, 85 \uf06dm, and 45 \uf06dm (GS215, GS160, GS85, and GS45). For that purpose, the determination of protein, ash, and total starch content and free and bound phenolic compounds was carried out. The highest content of total phenolic compounds was obtained in GS215 (3118.84 mg kg-1 d.w.), followed by GS160 (2499.11 mg kg-1 d.w.), GS85 (989.46 mg kg-1 d.w.), GSTQ (983.15 mg kg-1 d.w.), and GS45 (481.31 mg kg-1 d.w.). Therefore, the phenolic content decreased with the particle size decrease from 215 \uf06dm to 45 \uf06dm. Besides, there were no significant differences between the total phenolic content in GS85 and GSTQ. The fraction with 215 \uf06dm reported the highest protein and mineral salt content and presented rutin amounts four times higher than GSTQ

Helium identification with LHCb

The identification of helium nuclei at LHCb is achieved using a method based on measurements of ionisation losses in the silicon sensors and timing measurements in the Outer Tracker drift tubes. The background from photon conversions is reduced using the RICH detectors and an isolation requirement. The method is developed using pp collision data at √(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, corresponding to an integrated luminosity of 5.5 fb-1. A total of around 105 helium and antihelium candidates are identified with negligible background contamination. The helium identification efficiency is estimated to be approximately 50% with a corresponding background rejection rate of up to O(10^12). These results demonstrate the feasibility of a rich programme of measurements of QCD and astrophysics interest involving light nuclei

Curvature-bias corrections using a pseudomass method

Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy √(s)=13 TeV during 2016, 2017 and 2018. The biases are determined using Z→μ + μ - decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10-4 GeV-1 level, improves the Z→μ + μ - mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass

Optimization of two HPLC-DAD-MS methodologies using C18 and PFP core shell columns to determine free and bound phenolic compounds in waxy and non waxy barley samples

Barley (Hordeum vulgare vulgare L.) is an ancient cereal grain, which upon domestication has evolved from largely a food grain to a feed and malting grain. However, there is renewed interest throughout the world in barley food because of its nutritional value. Cereals are rich in phenolic acids and flavonoids and they are present in their free and conjugated forms. The highest concentration of phenolic acids and flavonoids is in the aleurone layer of cereal grains, but these compounds are also found in embryos and seed coat of grains. In this study, three varieties of waxy and three varieties of non waxy barley were analysed to determine their phenolic content by using two different core shell HPLC columns (C18 and PFP). The optimization of the two methods was developed and results were obtained in less than 15 minutes. Both columns were able to identify 10 free phenolic compounds and 6 bound phenolic compounds, however some differences in terms of LOD e LOQ were found between them. As far as phenolic composition concerns it can be said that the free phenolic fraction of barley is composed by flavan-3-ols and few phenolic acids, and waxy barley has higher content of phenolic compounds than non waxy barley samples. Besides, the bound phenolic fraction is exclusively formed by phenolic acids being particularly high the concentration of ferulic acid

Development of a CE-ESI-microTOF-MS method for a rapid identification of phenolic compounds in buckwheat

A sensitive CE-ESI-MS analytical method for the identification of buckwheat antioxidants has been developed. CE and ESI-TOF parameters (e.g. buffer composition and pH, sheath liquid composition, sheath liquid and gas flow rates, electrospray voltage) were optimized to obtain an optimal analytical separation and identification. The results confirmed the presence of phenolic acids, procyanidins and galloylated propelargonidins. The identification of swertiamacroside and 2-hydroxy-3-O-b-D-glucopyranosil-benzoic acid, found for the first time in our previous work, has been confirmed. Furthermore, 5,7,40-trimethoxyflavan and dihydroxy-trimethoxyisoflavan have also been tentatively identified for the first time in buckwheat

Molecular Characterization of Phospholipids by High-Performance Liquid Chromatography Combined with an Evaporative Light Scattering Detector, High-Performance Liquid Chromatography Combined with Mass Spectrometry, and Gas Chromatography Combined with a Flame Ionization Detector in Different Oat Varieties

Oat (Avena sativa L.) is an important crop produced in various regions of Europe and North America. Oat lipids are a heterogeneous mixture of acyl lipids and unsaponifiable components. The neutral lipids are mainly triacylglycerols and account for 50−60% of total oat lipids. Oat oil is also rich in polar lipids, that is, phospholipids and glycolipids. Characterization of oat polar lipids has largely been performed by thin-layer chromatography (TLC), but the composition of phospholipid classes has been poorly studied. The aim of our work was the determination of different phospholipids in Romanian oat samples. For that purpose, one commercial sample (Comun) and four pure varieties (Jeremy, Lovrin 1, Lovrin 27-T, and Mures) were used. High-performance liquid chromatography combined with an evaporative light scattering detector results allowed us to establish that phosphatidylethanolamine was the most representative phospholipid in all of the oat samples. In addition, high-performance liquid chromatography combined with electrospray ionization mass spectrometry analysis showed that C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:0, and C20:1 were the fatty acids bound to the glycerol backbone. Using first-preparative TLC and later gas chromatography, it was demonstrated that linoleic acid (C18:2) was the main fatty acid of the phospholipid fraction in all of the samples

Qualitative phenolic profile (HPLC-DAD-MS) from olive oil mill waste waters at different states of storage and evaluation of hydrolysis process as a pretreatment to recover their antioxidants

Olive oil mill waste water (OOMWW) represents a waste that it is generated during the extraction process of olive oil from olives and it is an important environmental problem because of the huge volume generated in the mills. Nevertheless, it is highlighted in literature the high concentration of antioxidants, especially phenolic compounds, in the OOMWW. Principally, the qualitative phenolic profiles of OOMWW differ depending on the technological process of production of olive oil and the time of storage. The aim of this work was to compare qualitatively the phenolic profile of OOMWW by HPLC-DAD-MS. Glucosilated secoiridoids as oleuropein and ligstroside, their aglycon derivatives and simple phenols were the principal compounds found in these matrixes. Furthermore, different hydrolysis reactions have been studied for the phenolic fraction in the oleuropein standard as well as in the OOMWWsamples.These steps have been evaluated as pretreatment for the selection and a possible subsequent recovery of most interesting phenolic compounds as hydroxytyrosol that has been proved to possess an important antioxidant activit

Pulsed electric field (PEF) as pre-treatment to improve the phenolic compounds recovery from brewers' spent grains

Brewers' spent grain (BSG) is the most abundant by-product obtained from beer production. However, it contains some bioactive compounds such as phenolic compounds, therefore, the valorization of BSG is important to recovery these compounds and reused them as functional ingredients in food industry. Therefore, in this work, pulsed electric field (PEF) has been used as extraction pre-treatment. PEF parameters such as electric field strength E (0.5, 1.5, 2.5 kV/cm), frequency (50, 100, 150 Hz) and total time of treatment (5, 10, 15 s) were optimized in order to maximize the content of flavan-3-ols, flavonoids, phenolic acid derivates and total free phenolic compounds. Optimal conditions to the maximum value of total free phenolic compounds were the following: 2.5 kV/cm, 50 Hz and 14.5 s. Concentrations of total free and bound phenolic compounds from BSG under these PEF optimum conditions were 2.7 and 1.7 times, respectively, higher than in case of the extraction without PEF pre-treatment, indicating an improvement in the phenolic recovery with the use of PEF as a pre-treatment in brewers spent grain samples

Optimization of a solid phase extraction and, sensitive HPLC-ELSD and HPLC-ESI-MS method for the determination of phospholipids in olive oil

Phospholipids belong to a polar lipid class of compounds and are particularly important as constituents of membrane of lipids in several food products. Some authors reported that some phospholipids found in vegetable oils display important biological activity and are useful in the prevention of certain diseases like arteriosclerosis. Nevertheless, phospholipids are poorly investigated as minor compounds in olive oil. In literature are present few articles focused on qualitative and quantitative analysis of phospholipids in virgin olive oil and, among them, an indirect determination of phospholipids by the phosphorous method that reported typical range values (21 to 124 mg/kg) of total phospholipids in veiled and filtered virgin olive oil and a study of individual phospholipids by NMR. Phospholipids’ isolation technique was essentially developed by liquid-liquid extraction (LLE). The aim of our work was to compare the effectiveness of LLE isolation methods with a direct separation and purification of olive oil's phospholipids with two different SPE sorbents (silica and diol). Furthermore, the extracts were analyzed by HPLC-ELSD and HPLC-ESI-TOF-MS to gain basic information useful for a possible identification of single components. To this aim a new separation method was established using an hydrophilic core shell liquid chromatography column

Effects of Fly Attack (Bactrocera oleae) on the Phenolic Profile and Selected Chemical Parameters of Olive Oil

The phenolic fraction of virgin olive oil influences both its quality and oxidative stability. One of the principal threats of the quality of olive fruit is the olive fly (Bactrocera oleae) as it alters the chemical composition. The attack of this olive pest has been studied in order to evaluate its influence on the quality of virgin olive oil (free acidity, peroxide value, fatty acid composition, water content, oxidative stability, phenols, and antioxidant power of phenolic fraction). The study was performed using several virgin olive oils obtained from olives with different degrees of fly infestation. They were acquired in different Italian industrial mills from the Abruzzo region. Qualitative and quantitative analyses of phenolic profiles were performed by capillary electrophoresis-diode array detection, and electrochemical evaluation of the antioxidant power of the phenolic fraction was also carried out. These analyses demonstrated that the degree of fly attack was positively correlated with free acidity (r ) 0.77, p < 0.05) and oxidized products (r ) 0.58, p < 0.05), and negatively related to the oxidative stability index (r)-0.54, p < 0.05) and phenolic content (r)-0.50, p < 0.05), mainly with secoiridoid compounds. However, it has been confirmed that the phenolic fraction of olive oil depends on several parameters and that a clear correlation does not exist between the percentages of fly attack and phenolic content