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Coffee is one of the most frequently consumed beverage that has an important place in our daily life. Owing to bioactive components in its content, it has antioxidant, antihypertensive, anti-inflammatory, immunoprotective, anti-carcinogenic effects on health. Within the scope of the study, it is aimed to compare the bioactive potential of commercially available Espresso, Americano, Macchiato, Latte, Cappuccino and Mocha coffee drinks by analyzing the antioxidant capacity (ABTS and DPPH Methods) and the total phenolic compound (Folin-Ciocalteu Method). The highest values were determined in the Espresso sample, which has the most intense coffee content; extractable, hydrolyzable, bioaccessible phenolic fractions were determined respectively as 28.15, 35.04, 30.28 μmol Troloks mL-1 according to TEACABTS and 14.69, 17.98, 9.84 μmol Troloks mL-1 according to TEACDPPH. By the increase of the milk amount in coffee samples, decrease was observed in the antioxidant capacity and total phenolic content results. Addition of steamed milk by steaming treatment showed relatively higher values compared to adding milk as hot. The bioaccessibility % of the samples varied between 41-48 % according to total phenolic content. [ABSTRACT FROM AUTHOR]

With the equivalent area of a 16-m telescope, ESPRESSO in 4UT mode allows to inaugurate high resolution spectroscopy for solar-type stars belonging to extragalactic globular clusters. We determine the chemical composition of an extragalactic blue straggler (BS). The star has a G magnitude of 19.01 and belongs to the globular cluster Pal12, that is associated to the Sagittarius dwarf galaxy. Abundances are computed by using high resolution spectroscopy and LTE analysis. Two 50 min ESPRESSO spectra, co-added, provide a signal-to-noise ratio of ∼25 with a resolving power R∼70 000. This allows us to measure with good precision abundance of several (13) elements. Li could help to distinguish between formation models of BS; we are able to set a 3σ upper limit of Li = 3.1, which is still too high to discriminate between competing models. The abundances we retrieve for the BS are compatible with those of giant stars of Pal 12 published in literature, re-analysed by us using the same procedure and line list. Small differences are present that can be ascribed to NLTE effects, but for Mg the BS shows a large under-abundance. The most likely explanation is that the BS atmosphere is dominated by gas processed through the Mg-Al cycle, but we have no suitable Al or Na lines to confirm this hypothesis. We show that ESPRESSO with 4UT can be used to derive precise abundances for solar-type stars fainter than magnitude 19. At these magnitudes a proper sky subtraction is needed and in crowded field the targets must be chosen with utmost care, to avoid contamination of the sky fibre from nearby stars. [ABSTRACT FROM AUTHOR]

In this study, a simple, fast, and effective methodology has been developed for the detection and quantification of seven phthalates potentially released in hot drinks from disposable containers used in vending machines. The authors determined the optimal conditions to be applied during the various steps of extraction of seven phthalates (DMP, DEP, DBP, DiBP, DEHP, DNOP, and DDP) from hot beverages using a model solution. The extraction and preconcentration technique used was ultrasound–vortex-assisted dispersive liquid–liquid microextraction (UVA-DLLME) followed by gas chromatographic analysis obtaining recoveries from 66.7% to 101.2% with precision and reproducibility <6.3% and <11.1%, respectively. The influence of waiting time, from the dispensing of the drink to its actual consumption, for the extraction of molecules was investigated, obtaining a temporal release profile slightly shifted towards the PAEs with higher molecular weight and vice versa for those with low molecular weight. In addition, the best instrumental parameters to be applied during the analysis of the extracts obtained were established. This optimization was carried out using GC-FID, whereas the analysis of real samples was carried out by means of GC-IT/MS for ultra-trace analysis purposes; limits of detection (LODs) ranging between 0.8 ng mL−1 and 15.4 ng mL−1 and limits of quantification (LOQs) from 1.6 ng mL−1 to 35.8 ng mL−1, both of them lower than those found by FID, were obtained. [ABSTRACT FROM AUTHOR]

The hot Neptune desert, a distinct lack of highly irradiated planets in the size range of Neptune, remains one of the most intriguing results of exoplanet population studies. A deeper understanding of the atmosphere of exoplanets sitting at the edge or even within the Neptune desert will allow us to better understand if planetary formation or evolution processes are at the origin of the desert. A detection of sodium in WASP-166 b was presented previously with tentative line broadening at the |$3.4\, \sigma$| with the HARPS spectrograph. We update this result with two transits observed with the ESPRESSO spectrograph, confirming the detection in each night and the broadened character of the line. This result marks the first confirmed resolved sodium detection within the Neptune desert. In this work, we additionally highlight the importance of treating low-SNR spectral regions particularly where absorption lines of stellar sodium and planetary sodium overlap at mid transit – an important caveat for future observations of the system. [ABSTRACT FROM AUTHOR]

The coffee extraction methods modify the structure of the foam (when it is present) and the sensory profile of the beverage. In this research, three ways of extracting and two varieties of 100% Arabica were compared. Nineteen bars and fifteen bars were applied to the coffee thanks to the use of compatible capsules and machines. The method with the moka was considered, which acts at low pressures and does not allow the formation of foam (crema). In addition, the Brazil and Guatemala Arabica varieties were considered to understand the extent to which Arabica coffee can respond in structural and sensorial terms to the extraction techniques applied. The results show that 19-bar espresso coffees have a very stable crema with very small bubbles, which give a uniform and fine structure to the coffee crema. On the contrary, the pressure at 15 bars generates more unstable foams and bubbles that tend to be disproportionate, with more marked effects in the Brazil variety. The sensory profiles of the coffees respond to the extraction techniques applied. While the coffee extracted with the moka has sensory descriptors with rather low values, those obtained at 19 and 15 bars have much wider profiles. In conclusion, different pressure intensities to the coffee extraction affect the quality of crema and the solubilization of organoleptically active compounds. [ABSTRACT FROM AUTHOR]

This study quantified, for the first time, 2-isopropylmalic and 3-isopropylmalic acids, in green, roasted and espresso coffee by UHPLC-MS/MS. Moreover, it reports the influence of postharvest processing methods (natural, washed and honey) on their content. New extraction techniques were developed and validated from three coffee matrices (green, roasted and espresso). Honey coffee exhibited levels substantially higher of 2-isopropylmalic acid than those processed by natural and washed methods (p < 0.05). Specifically, 2-isopropylmalic acid levels in honey green, roasted and espresso coffee samples were 48.24 ± 7.31 ng/g, 168.8 ± 10.88 ng/g and 177.5 ± 9.49 ng/g, respectively. This research highlights the significant impact of processing methods on the chemical profile of coffee and introduces 2-isopropylmalic and 3-isopropylmalic acids as potential quality indicators. Moreover, it suggests that the fermentation stage during processing may play a crucial role in their formation, laying the foundation for optimizing coffee processing to enhance quality. [Display omitted] • First quantification of 2-IPMA and 3-IPMA in coffee. • Honey processing boosts 2-IPMA levels. • Novel extraction methods for malic acid derivatives in coffee. • Link between processing methods and chemical profiles. • Potential new indicators of coffee quality. [ABSTRACT FROM AUTHOR]

The present work examined how the esthetic impression caused by a specific mug selection seems to influence the expected flavor elicited by a coffee beverage. Participants from Mexico viewed online photographs of espresso, Americano, latte and cappuccino presented in two different mugs, including a transparent glass mug and a white ceramic mug. The type of mug influenced participants' subjective ratings of the drinks. Espresso and Americano were expected to be more aromatic, bitter, hotter and more intense when served in a transparent glass mug rather than in a white ceramic mug. Results extend the knowledge of consumer preferences and bring an idea for the best way to better fulfill customer's sensory expectations. [ABSTRACT FROM AUTHOR]

The instrumental equipment of an espresso coffee machine has a remarkable influence on the extraction of the espresso coffee (EC). This study aims to evaluate the effect of different perforated disc heights and filter baskets, two fundamental parts of the espresso coffee machine, on EC carbohydrates content and composition. Four different heights (4–7 mm) of perforated discs and two different filter baskets were used to prepare Italian style EC and evaluate the feasibility of lowering the amount of ground coffee while keeping the same quality of the standard Italian espresso. Arabica and Robusta coffee beans, with 12 and 14 g of roasted coffee powder, were used to prepare 40 mL of EC, split in two cups. The content of total solids, high molecular weight material and polysaccharides, such as galactomannans (GM) and arabinogalactans (AG), were compared. The results show that the increase of the height of perforated disc affected the extraction of the polysaccharides content in the cup, with a decrease of GM and AG. As a conclusion, the configuration of perforated disc height and the filter used was shown to modulate the chemical profile of EC brew, with impact on espresso coffee cup quality. [ABSTRACT FROM AUTHOR]

There are different methods to extract and brew coffee, therefore, coffee processing is an important factor and should be studied in detail. Herein, coffee was brewed by means of a new espresso professional coffee machine, using coffee powder or portioned coffee (capsule). Four different kinds of coffees (Biologico, Dolce, Deciso, Guatemala) were investigated with and without capsules and the goal was to classify the volatiloma of each one by Small Sensor System (S3). The response of the semiconductor metal oxide sensors (MOX) of S3 where recorded, for all 288 replicates and after normalization ∆R/R0 was extracted as a feature. PCA analysis was used to compare and differentiate the same kind of coffee sample with and without a capsule. It could be concluded that the coffee capsules affect the quality, changing on the flavor profile of espresso coffee when extracted different methods confirming the use of s3 device as a rapid and user-friendly tool in the food quality control chain. [ABSTRACT FROM AUTHOR]

The sorting of biological cells or particles immersed in a fluid is a frequent goal in the domain of microfluidics. One approach for such sorting is in using the inertial effects that are present in curved channels. In this study, we propose a new approach of inertial focusing of cells in microfluidic devices. The investigated channels had the form of a helical channel with a circular cross-section, and the cells were spherical. We identified the key parameters that influence the cell sorting results through multiple computational simulations using a modelling tool PyOIF within the package ESPResSo. We found that spherical cells could be sorted with respect to their size in helical channels since their stabilised positions are located in different parts of the channel cross section. The location of the stabilised position is a function of the fluid parameters, the geometrical parameters of the helical device, and the size of the immersed cells. [ABSTRACT FROM AUTHOR]

Doping has been shown to cause significant electronic structure perturbation, resulting in the formation of mind-gap states in semiconductors. Since the beginning of 2005, research in this area has literally exploded, resulting in an everincreasing number of papers devoted to graphene and its unique properties. Quantum Espresso was used to investigate the structural and electronic properties of graphene nanosheet. It was observed that pure graphene produces zero energy gap while 0.773eV when the hydrogen atom was doped. Different patterns were observed in Total Density of State (TDOS) and Projected Density of State (PDOS) due to the doping effect. [ABSTRACT FROM AUTHOR]

It is commonly assumed that coffee particles swell during filtration, but it has not been clarified how different degrees of swelling affect the extraction. In this article, we propose a grain swelling model to investigate the influences of swelling on both intra-grain and inter-grain transport. The swelling is modeled through a diffusion process of excess water into the grains. The geometric expansion of the grains is connected to the local concentration of excess water through a specified deformation gradient tensor. Diffusion of soluble compounds inside the grains is coupled with the swelling dynamics through a modified diffusion equation. Inter-grain transport is modeled by solving the Navier–Stokes equation and diffusion equations. This model is solved numerically in the framework of smoothed particle hydrodynamics, and it is used to simulate the extraction of a minimal coffee bed setup and to investigate the effect of a small degree of particle swelling (< 8 % in size) on the extraction kinetics. It is found that under the normal operating parameter regime of espresso filtration, swelling affects the extraction mainly through the change of inter-grain transport. Swelling also alters the diffusion inside the grains, but this process has a secondary effect on the extraction. In general, swelling slightly impedes the extraction rate, but enhances the strength considerably at both fixed brewing time and fixed brewing volume. Our results justify the endeavor in the literatures to clarify the effect of possible swelling on brewing and preparation variables during coffee extraction. [ABSTRACT FROM AUTHOR]

An untargeted metabolomics approach combined with sensory analysis was used to depict the impact of different traditional Italian extraction methods (i.e., Espresso, Neapolitan, Moka) along with Filter, on Coffea arabica and Coffea canephora var. robusta beverages. To this aim, polyphenols, Maillard reaction products, and coffee metabolites were screened by high resolution mass spectrometry and elaborated through both unsupervised and supervised multivariate statistical approaches. Multivariate statistics showed a distinctive chemical profile for Espresso preparation, while Moka and Neapolitan were very similar. The orthogonal projection to latent structures and discriminant analysis allowed the identification of 86 compounds showing a high VIP discrimination score (i.e., > 0.8). The 2,5-dimethyl-3-(methyldithio)-furan was a marker for the Filter preparation, while 1,2-disinapoylgentiobiose characterized both Filter and Neapolitan extractions. Caffeine (known to be a bitter compound) accumulated highly in Filter vs. Espresso, although at the sensory profile, bitterness was more perceived in Espresso. Vegetal aroma carried by pyrazines, pyridines, and phenolic acids were markers of Espresso, with Robusta showing higher values than Arabica. Notwithstanding, our findings showed that the extraction process played a hierarchically higher role in driving the chemical composition of the beverages when compared to coffee species. [ABSTRACT FROM AUTHOR]

The detection of 6Li in Spite plateau stars contradicts the standard big bang nucleosynthesis prediction, known as the second cosmological lithium problem. We measure the isotopic ratio 6Li/7Li in three Spite plateau stars: HD 84937, HD 140283, and LP 815−43. We use 3D non-local thermodynamic equilibrium radiative transfer and for the first time apply this to high-resolution, high signal-to-noise ratio data from the ultra-stable ESPRESSO/Very Large Telescope spectrograph. These are among the best spectra ever taken of any metal-poor stars. As the measurement of 6Li/7Li is degenerate with other physical stellar parameters, we employ Markov chain Monte Carlo methods to find the probability distributions of measured parameters. As a test of systematics, we also use three different fitting methods. We do not detect 6Li in any of the three stars, and find consistent results between our different methods. We estimate 2σ upper limits to 6Li/7Li of 0.7, 0.6, and 1.7 per cent, respectively, for HD 84937, HD 140283, and LP 815−43. Our results indicate that there is no second cosmological lithium problem, as there is no evidence of 6Li in Spite plateau stars. [ABSTRACT FROM AUTHOR]

Coffee powder is obtained with a grinding machine. Espresso coffee is prepared when hot water is forced under pressure through the puck of coffee powder, and the optimal espresso flow rate is 1 g s−1. However, this flow rate can change for different extractions, forcing baristas to frequently change the setup of the grinder. Grinding grade is one of the most important sources of variation in the quality of espresso. This study tests an innovative method to prepare coffee powder puck, designed to reduce variability in flow rate between extractions. The method is based on stratified layers of ground coffee with different granulometry, and it was tested in three trials with different coffees and grinders. The flow rate associated with the new method (Patent WO/2020/148258- PCT/EP2020/050773) was more stable than the rate in a conventional system, reliability was optimized by placing larger coffee particles at the bottom, and finer particles at the top of the filter basket. [ABSTRACT FROM AUTHOR]

Dopo un lungo periodo senza la possibilità di studiare medicina nella Svizzera italiana, nel 2014 si è deciso di istituire una facoltà di scienze biomediche presso l'Università della Svizzera italiana a Lugano. Nella stessa università, dal 2020, è possibile frequentare un programma di Master triennale in medicina in inglese, svolto in collaborazione con le università di lingua tedesca di Basilea e Zurigo per la formazione a livello di Bachelor. Al letto del paziente, invece, viene usata la lingua italiana. Lo studio pilota di tipo esplorativo che si propone qui di seguito ha l'obiettivo di illuminare per la prima volta in modo sistematico la prospettiva degli studenti in questa formazione multilingue. Dopo una descrizione delle pratiche linguistiche in Svizzera, compresi gli aspetti migratori relativi alla formazione universitaria, vengono presentati i risultati di un sondaggio condotto al fine di ricavare informazioni sulle competenze linguistiche. Questi dati sono stati raccolti tra aprile e maggio 2022 in due parti. La prima parte prevede un questionario online in cui sono stati ottenuti dati utili a determinare quali competenze gli studenti hanno di fatto nelle lingue coinvolte e quali atteggiamenti linguistici esistono. Nella seconda parte sono state condotte interviste semistrutturate necessarie a determinare le lingue utilizzate nell'interazione concreta con i pazienti, i medici e i compagni di corso. I risultati mostrano che l'apprendimento dell'italiano inizia perlopiù solamente all'università e che la valutazione della competenza orale è più alta di quella scritta. Gli atteggiamenti verso l'italiano sono molto incentrati sul contesto d'uso e sul contesto di acquisizione della lingua. Inoltre viene ripetutamente espresso il desiderio di un livello più alto di competenza nella comunicazione quotidiana, e con esso un maggior grado di empatia. [ABSTRACT FROM AUTHOR]

Summary: Specialty coffee (SC) has been showing an increasing interest from the consumers which appreciate its traceability and the peculiar flavours from each single origin. Additionally, the processes to which coffee fruits underwent to get green coffee characterise the beans in terms of macromolecules acting as substrates during the roasting. This work evaluates via sensory analysed eight SC, roasted at light, medium, and dark level, submitted to Italian espresso extraction, to assess how different roasting levels exalt the expected cup profile obtained by the suppliers via cupping in origin countries. Finally, roasted beans were characterised for physico‐chemical features (pH, titratable acidity, caffeine, melanoidins, polyphenols and acrylamide). Sensory analysis demonstrated that the intermediate roasting level and espresso extraction match better attributes from in‐origin cupping. Melanoidins (mmol g−1 coffee d.b.) was able to discriminate among roasting levels (light 0.12 ± 0.01; medium 0.13 ± 0.003; dark 0.14 ± 0.01; α = 0.05). Acrylamide analyses ensured compliance with the food safety standards (light 301.9 ± 37.2 ppb; medium 126.1±19ppb; dark 107.9 ± 22.5ppb). Physico‐chemical features were able to cluster samples from different origins within the same roasting level (α = 0.05). Results showed correlations (α = 0.01) between sensory analysis and physico‐chemical values: direct for caffeine and astringency, reverse for perceived acidity in relation to astringency, roasted, dried fruits and nutty notes. [ABSTRACT FROM AUTHOR]

Coffee capsules have become one of the most used methods to have a coffee in the last few years. In this work, coffee was prepared using a professional espresso coffee machine. We investigated the volatilome of four different polypropylene coffee capsule typologies (Biologico, Dolce, Deciso, Guatemala) with and without capsules in order to reveal the possible differences in the VOCs spectra. The volatilome of each one was singularly studied through an analysis by gas chromatography and mass spectrometry (GC–MS), checking the abundance of different VOCs in coffee extracted with and without a capsule protection and compared to its related sample. Furthermore, ANOVA and Tukey tests were applied to statistically identify and individuate the possible differences. As a result, it was found that coffee capsules, offer advantages of protecting coffee from oxidation or rancidity and, consequently extended shelf life as well as did not cause a reduction of volatile compounds intensity. Therefore, it is possible to conclude that the aroma of polypropylene coffee capsule extraction is not damaged compared to a traditional espresso. [ABSTRACT FROM AUTHOR]