La nuova scheda per l’analisi sensoriale dell’aceto balsamico tradizionale

L’analisi sensoriale è uno strumento molto potente e utile nell’attribuzione qualitativa degli alimenti, essa è complementare alle analisi chimiche e strumentali perché porta informazioni di altra natura, complesse e non rilevabili in altro modo. Per questo motivo, i tentativi di “tarare” l’analisi sensoriale sulla composizione del balsamico sono infruttuosi e concettualmente scorretti. Un presupposto essenziale per assicurare l’efficacia dell’analisi sensoriale è che essa sia svolta con procedure che massimizzino l’indipendenza di giudizio degli assaggiatori sia all’interno del panel che nella sequenza dell’analisi del campione. In questo contesto gioca un ruolo chiave sia il metodo di assaggio che la scheda per la raccolta delle espressioni di gradimento

Análisis comparativo del espectro infrarrojo de dos estrellas masivas

Las estrellas masivas, aunque pocas en número, son objetos de fundamental importancia ya que dominan el comportamiento energético, químico y dinámico de las regiones donde habitan. Como ya se sabe las estrellas masivas viven poco tiempo (pocos millones de años) y durante su juventud están embebidas en su medio polvoriento natal, invisibles en el rango visible. Teniendo esto en cuenta hemos comenzado hace algunos años la obtención de espectros infrarrojos con GNIRS, en su modo de alta resolución (R ∼ 17800), de todas las estrellas estándares de clasificación del tipo O. En esta charla se describe el procesamiento y análisis de los espectros infrarrojos de dos estrellas tipo O4: HD 46223 y HD 15570. La reducción fue una tarea no trivial debido a la contaminación telúrica y la dificultad que presenta la eliminación de las líneas propias de la estándar telúrica. Se pudieron identificar la mayorı́a de las líneas de Hidrógeno presentes en las bandas J, H y K. También fueron identificadas varias líneas de helio neutro y ionizado ası́ como iones de metales como silicio, carbono y oxígeno. De esta manera se propone un criterio de clasificación en clase de luminosidad para este subtipo utilizando la progresión de la linea He II λ1.012 μm.Facultad de Ciencias Astronómicas y Geofísica

Feasible acetic acid fermentations of alcoholic and sugary substrates in combined operation mode

Starting from small-scale batch cultivations, acetic acid fermentations in static and submerged systems have been performed by a single acetic acid bacterial strain. To provide user-friendly selected starter cultures for industry, the versatility of these cultures in using different oxidation substrates under different conditions was assessed. In all cases, vinegars with the desired acetic acid, residual ethanol and reducing sugar contents were obtained. An appropriate small-scale batch cultivation subjected to strict process control was pivotal for obtaining the desired acetic acid concentrations and an active culture for submerged fermentation. This achievement enabled the generation of selected starter cultures for submerged vinegar production, which reached an acetic acid content of 8.00\u20139.00% (w/v), as well as prototype-scale vinegar production. The production of vinegars with reducing sugars in the range of 15.00\u201327.00 (% w/v) was achieved, and cellulose production was avoided. The dominance of the microbial culture in this process was shown via (GTG)5-PCR. These results are valuable for introducing the use of selected acetic acid bacteria cultures in industrial vinegar production

Sensory analysis of traditional balsamic vinegars: current state and future perspectives

Quality evaluation of traditional balsamic vinegar (TBV) is primarily based on sensory analysis. For every TBV batch, official sensory panels give a final score, which determines its assessment into quality and price categories. Therefore, an effective and objective sensory analysis is a core aspect in TBV production and marketing and it should fulfill at least two conditions: i) the panelists have been properly trained on the TBV features; ii) the panelists have to be free from any psychological and physical conditions which might affect human judgments. Traditionally, a panel of trained members assesses the TBV sensory attributes evaluating visual, olfactory, gustatory and trigeminal features at the same time. The result is that visual appearance significantly affects the subsequent stages of the sensory analysis, and even the olfactory and gustatory sensations will greatly affect each other. The aim of this work was to review the procedures for the sensory analysis of TBV and to define a set of TBV attributes. A new assessment questionnaire has been proposed to establish the appropriate sensory vocabulary for a complete description of TBV sensory properties

Fermentation strategy to produce high gluconate vinegar

Gluconic acid is a non-volatile acid that has many applications in food, pharmaceutical and cleaning fields. Gluconic acid has been detected as main oxidation product of Acetobacter and Gluconobacter strains growing on grape must, and it plays an important role in Traditional Balsamic Vinegar. Commonly, high gluconate vinegars have a greater physical stability and a greater preference by consumers because are perceived less pungent. In fact, gluconic acid reduces the pH and increases fixed acidity of the vinegar without increasing the sensation of pungency typical of acetic acid. Its taste is acid but mild sweet and, therefore, gluconic acid has influence on the sensory complexity of the vinegar. The aim of this work is to set up a fermentation procedure that improves the quality of balsamic vinegar by using selected yeasts and acetic acid bacteria strains able to oxidize glucose in grape must-based media having a different sugars concentration. In particular, Saccharomycodes ludwigii UMCC 297 and Acetobacter pasteurianus UMCC 1754 strains were chosen as selected starter cultures for small-scale fermentation of cooked grape must, to evaluate the physical-chemical parameters affecting gluconic acid production in the obtained vinegar. The strains used and the control of all production process have been fundamental for obtaining the vinegar with the desired characteristics

I balsamici: fermentazione acetica, viscosit\ue0 e parametri sensoriali

La produzione di aceto di vino \ue8 un processo che utilizza materie prime dal valore relativamente basso per ottenere un prodotto che raggiunge prezzi relativamente alti. La categoria merceologica che maggiormente beneficia dell\u2019uso di questi prodotti \u201cpoveri\u201d \ue8 quella relativa ai condimenti alimentari agrodolci a base di mosto concentrato e/o cotto e aceto di vino, cio\ue8 tutti i prodotti che hanno un esplicito riferimento al termine \u201cbalsamico\u201d. Indubbiamente la diffusione di prodotti balsamici sul mercato \ue8 in forte crescita, anche grazie allo sviluppo di nuove forme di presentazione e di utilizzo del prodotto base (come glasse, creme, spume, spray) e una continua ricerca dell\u2019aromatizzazione distintiva e particolare (attraverso l\u2019utilizzo di fragranze o seguendo processi di produzione peculiari). Nelle province di Modena e Reggio Emilia \ue8 concentrata l\u2019intera produzione di aceti \u201cbalsamici\u201d a denominazione protetta italiani: due DOP per l\u2019aceto balsamico tradizionale di Modena (ABTM) e quello di Reggio Emilia (ABTRE) e una IGP per l\u2019aceto balsamico di Modena (ABM). L\u2019ABT non \ue8 aceto di vino bens\uec di mosto cotto, tuttavia nell\u2019ABM l\u2019acidit\ue0 deriva dal comune aceto di vino ottenuto per fermentazione in sommerso. La linea di prodotti sviluppati coniuga gli aspetti migliori dal punto di vista qualitativo ed economico delle due tipologie, introducendo numerose innovazioni: i) le fermentazioni dirette e in condizioni statiche consentono un risparmio energetico notevole e favoriscono la formazione di composti secondari sensorialmente positivi, anche grazie all\u2019impiego di lieviti e batteri acetici specifici e selezionati appositamente per le loro caratteristiche fermentative; ii) il processo di concentrazione del mosto tramite cottura \ue8 assente o fortemente limitato mentre l\u2019invecchiamento \ue8 accelerato tramite l\u2019utilizzo di tecniche di condizionamento ambientale ecosostenibile; iii) non sono presenti additivi e conservanti di nessun genere in quanto vengono impiegate tecniche di conservazione basate sull\u2019impiego oculato degli stessi microrganismi usati nelle fermentazioni; iv) le condizioni di cottura applicate limitano al minimo la formazioni di composti tossici

Spritz: General Relativistic Magnetohydrodynamics with Neutrinos

We here present a new version of the publicly available general relativistic magnetohydrodynamic (GRMHD) code $\texttt{Spritz}$, which now includes an approximate neutrino leakage scheme able to handle neutrino cooling and heating. The leakage scheme is based on the publicly available $\texttt{ZelmaniLeak}$ code, with a few modifications in order to properly work with $\texttt{Spritz}$. We discuss the involved equations, physical assumptions, and implemented numerical methods, along with a large battery of general relativistic tests performed with and without magnetic fields. Our tests demonstrate the correct implementation of the neutrino leakage scheme, paving the way for further improvements of our neutrino treatment and the first application to magnetized binary neutron star mergers. We also discuss the implementation in the $\texttt{Spritz}$ code of high-order methods for a more accurate evolution of hydrodynamical quantities.Comment: 34 pages, 16 figures. The code is available on Zenodo as version 1.1.0 at https://doi.org/10.5281/zenodo.3689751. Initial data and equation of state used in this paper can be downloaded from https://drive.google.com/drive/folders/1kGBRW_AhKjHrOi76uXXPRyaCc1BfgqQN?usp=sharin

Engineering-geological modeling for supporting local seismic response studies. Insights from the 3D model of the subsoil of Rieti (Italy)

A high-resolution 3D engineering-geological model of the subsoil can be derived by integrating stratigraphic and geophysical data in order to represent reliably the geological setting, and therefore support several geological studies such as local seismic response analyses. In this study, we show how an accurate 3D engineering-geological model suggests the proper seismic response modeling approach (1D or 2D) in a peculiar and complex geological context, such as the historical city center of Rieti (Italy), selected as test site, and characterized by important lateral heterogeneities between stiff travertine and alluvial soft deposits. The proposed methodology involves three steps: (i) conceptual geological modelling, obtained from data and maps of literature; (ii) engineering-geological modeling, validated through geophysical data; and (iii) a 3D model restitution achieved by a geodatabase (built basing on the previous steps), that collects, stores, reliably represents, and integrates properly the geospatial data. The analysis of seismic ambient noise measurements specifically available for the study area allowed to infer the shear wave velocity value for each lithotecnical unit and to retrieve some additional stratigraphies. These synthetic log stratigraphies allowed to improve the detail of the geodatabase and therefore a more accurate 3D geological model. Such a reliable engineering-geological model of the subsoil is required to perform a site-specific seismic response characterization which is a fundamental tool in the framework of seismic risk management