A Metabolomic Approach to the Study of Wine Micro-Oxygenation

Wine micro-oxygenation is a globally used treatment and its effects were studied here by analysing by untargeted LC-MS the wine metabolomic fingerprint. Eight different procedural variations, marked by the addition of oxygen (four levels) and iron (two levels) were applied to Sangiovese wine, before and after malolactic fermentation

Vinegar production from fruit concentrates: effect on volatile composition and antioxidant activity

Vinegar stands as a highly appreciated fermented food product due to several functional properties and multiple applications. This work focuses on vinegar production from fruit wines derived from fruit concentrates, to attain a food product with nutritional added value. Four fruit vinegars (orange, mango, cherry and banana), were produced and characterized, with total acidities of 5.3 ± 0.3% for orange, 5.6 ± 0.2% for mango, 4.9 ± 0.4% for cherry and 5.4 ± 0.4% for banana. Acetification showed impact on aroma volatiles, mainly related to oxidative reactions. Minor volatiles associated with varietal aroma were identified, monoterpenic alcohols in orange vinegar, esters in banana vinegar, C13-norisoprenoids in cherry vinegar and lactones in mango vinegar, indicating fruit vinegars differentiated sensory quality. Total antioxidant activity analysis by FRAP, revealed fruit vinegars potential to preserve and deliver fruit functional properties. Antioxidant activity of fruit vinegars, expressed as equivalents of Fe2SO4, was of 11.0 ± 1.67 mmol L1 for orange, 4.8 ± 0.5 mmol L1 for mango, 18.6 ± 2.33 mmol L1 for cherry and 3.7 ± 0.3 mmol L1 for banana. Therefore, fruit vinegars presented antioxidant activity close to the reported for the corresponding fruit, and between 8 and 40 folds higher than the one found in commercial cider vinegar, demonstrating the high functional potential of these novel vinegar products.Authors would like to acknowledge the financial funding of: FruitVinegarDRINK QREN Project (Ref. 23209), Project "BioInd-Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" Co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER and the FCT Strategic Project Pest OE/EQB/LA0023/2013. Authors would also like to acknowledge the participation of Mendes Goncalves S.A. and Frulact S.A. staff, for the active input, which led to the work basis and rationale.info:eu-repo/semantics/publishedVersio

Produzione di Vini in assenza di SO2: Influenza del lisozima e del tannino di galla sulla componente volatile

Negli ultimi anni, l\u2019impiego dell\u2019 SO2 in vinificazione \ue8 stato messo in discussione per i suoi effetti tossici sulla salute umana. Per poter condurre una vinificazione a bassi dosaggi di SO2 o in totale assenza di questa \ue8 indispensabile individuare e sperimentare sostanze che possano svolgere un\u2019azione sostitutiva e di pari efficacia. Alcune interessanti soluzioni sembrano essere rappresentate dal lisozima, un enzima ad attivit\ue0 antibatterica in grado di controllare la fermentazione malolattica e gli eventuali spunti lattici nei vini. L\u2019attivit\ue0 antiossidasica che questo enzima non \ue8 in grado di svolgere, potrebbe essere affidata ai tannini enologici, coadiuvanti tecnologici in grado di prevenire l\u2019ossidazione in vinificazione. In questo studio, sono stati valutati gli effetti della sostitutizione della SO2 in fase pre-fermentativa attraverso l\u2019impiego di lisozima e tannino di galla, in particolare a carico della componente volatile dei vini. I risultati hanno messo in evidenza che sia l\u2019SO2 che il lisozima prevengono lo sviluppo di eventuali fermentazioni anomale. Lo studio sulla componente volatile ha messo in evidenza delle differenze fra i prodotti finiti a carico dei contenuti in alcoli, esteri ed acidi: i risultati ottenuti suggeriscono che il lisozima ed il tannino di galla possono rappresentare un\u2019alternativa promettente all\u2019impiego della SO2 per la produzione di vini a ridotto contenuto di solfiti. La composizione della frazione aromatica dei prodotti finiti \ue8 stata influenzata dai differenti protocolli di vinificazione sviuppati, soprattutto per quanto riguarda la classe degli alcoli e degli esteri etilic

Assessment of Sensory and Texture Profiles of Grape Seeds at Real Maturity Stages Using Image Analysis

The usefulness of digital image analysis in estimating sensory attributes of grape seeds in relation to maturation level was evaluated for the first time. Seeds from Syrah grapes harvested throughout the ripening period were grouped according to maturity using the DigiEye® system. The discriminant ability, homogeneity, repeatability, and uniformity of a sensory panel were assessed after training on grape seeds. The aim was to evaluate the use of digital image techniques in order to accurately establish the maturity level of grape seeds, based on sensory and textural features. All sensory attributes (color, hardness, cracking, vegetal, bitterness and astringency) showed significant (p < 0.05) correlations with the chemical maturity stage. Color and vegetal (sensory attributes), together with deformation energy (instrumental texture parameter) (De), allowed for the classification of the seeds into four real maturity stages, hence their usefulness as grape seed ripening indicators. Significant (p < 0.05) and high-correlation factors were also found between instrumental and sensory attributes. Therefore, digital analysis can be a useful tool to better define the maturity stage in the vineyard, and to dispose of grape seeds with well-defined sensory profiles for specific oenological applications. This could help to determine the optimal harvest date to manage winemaking, in order to produce high quality wines in warm climates

Enzymatic protein hydrolysates of a residue from grape by-products industry for winemaking application: influence of the starting material and hydrolysis time

Large quantities of defatted grape seed meal (DGSM) are discarded annually in the grape pomace industry. This residue could be exploited as a new source of non-animal protein to improve the chemical and color stabilization of red wines from warm regions. Different protein hydrolysates have been characterized, considering two different variables in their obtaining: type of raw material (DGSM from white and red grape pomaces) and hydrolysis time (1 and 4 h). The protein content of the hydrolysates, their molecular weight distribution, color, amino acid and peptide composition, and antioxidant activity were evaluated. Products obtained were mainly influenced by the type of raw material, regardless of the hydrolysis time. Hydrolysates from red DGSM displayed a higher protein content (∼67.4%) and protein yield (∼28.9%), visually perceptible (ΔE*ab > 3) lower lightness (∼23.3) and color intensity (∼13.2), and a greater variety of peptides related to red wine color stabilization. However, hydrolysates from white DGSM showed a higher amino acid content and antioxidant capacity (∼33.5 µmol TE/g, by DPPH; ∼3710.9 µmol TE/g, by ORAC). According to the results obtained, both red and white DGSM are susceptible starting materials to be selected as optimal for application in winemaking, fixing 1 h as hydrolysis time.</p

Characterization and Differentiation of High Quality Vinegars by Stir Bar Sorptive Extraction Coupled to Gas Chromatography-Mass Spectrometry (SBSE-GC-MS)

A stir bar sorptive extraction gas chromatography\u2013mass spectrometry (SBSE\u2013GC\u2013MS) method has been used for the characterization of the volatile composition of 26 high quality vinegars of three different protected geographical indications (traditional balsamic vinegar of Modena, balsamic vinegar of Modena, and Sherry vinegar). SBSE technique provided the identification of 113 volatile compounds, which belong to different chemical families (short-chain esters, acids, acetates and alcohols, phenols, lactones and benzenic and furanic compounds). 39 volatile compounds were never previously reported in wine vinegars. This characterization contributed to the differentiation of the 100% of the studied samples on the basis of raw material (two different types of wine, and cooked must), aging type (static and dynamic) and aging time (&lt;5 years, between 5 and 25 years, and >25 years). Furanes and terpenes together with acids and alkanes were the most discriminant variables for raw material and aging time, respectively, whereas for aging type, these ones were acetates and esters

TECHNICAL TRAINING COURSES: A TEACHING METHODOLOGY WITH A PRACTICAL POINT OF VIEW

Taking into account the new European Higher Education Area (EHEA), the internationalization and cooperation among different universities is an essential aspect to be developed. The new Agrifood Campus of International Excellence (CeiA3) of Andalusia provides the possibility to researchers and professional workers of the Agrifood sector of improving their training by means of different courses of specialization called \u201cTechnical Training Courses\u201d. A group of professors from the University of C\ue1diz, with the cooperation of a foreign professor from the University of Bologna (Italy) developed one of these courses in the academic year 2011/2012, whose title was \u201cAnalysis of oenological products by means of advanced chromatographic techniques\u201d, and it was focused on graduates and professional of the agricultural sector from any part of Andalusia. The length of the course was 35 hours, a part of it was taught in English. The main teaching objectives of this course were on the one hand, to develop lessons from a very practical point of view, avoiding the typical master class and to establish a close report with students. And on the other hand, to improve the training of researchers and professional workers, offering them the possibility of receiving a course in a different place from them, with the most exhaustive and comprehensive scientific material. The mobility of the students was finally achieved because a high percentage of them were external from the University of C\ue1diz. Moreover, as can be derived from a final questionnaire submitted to students, the obtained opinions of the course were excellent and all the students were very satisfied with both the scientific material provided and the practical teaching methodology. However, only with a low number of students (10), this methodology could be successfully carried out. Finally, during the development of the mentioned course, the different professors involved improved as well several adeptness or competences, that are included in the Grade titles and therefore are evaluated during the academic teaching activity. Examples of these competences can be the following: oral expression, work group, resolution of practical scientific problems or communication in a second languag