39 research outputs found
Effect of supercritical CO2 and olive leaf extract on the structural, thermal and mechanical properties of an impregnated food packaging film
Poly(ethylene terephthalate)/polypropylene (PET/PP) films containing olive leaf extract (OLE) were obtained by supercritical solvent impregnation (SSI) in batch (BM) and semi-continuous (SM) modes. The study focused on the impact of pressure, temperature, CO2 flow and OLE on the properties of the impregnated films. Thermal analysis of non-impregnated samples revealed a decrease in the crystallinity of PP layer treated at 35 °C and an increase in the Tg of PET treated at 55 °C due to CO2 sorption. In impregnated samples, high pressures caused a decrease in the crystallinity of PP layer, whereas PET layer remained unaffected. Higher pressures favour impregnation in BM, whereas different trends were found for SM impregnations. Although the film properties were not compromised after impregnation, the CO2 stream used in SM slightly weakened the impregnated films. Overall, conditions of 400 bar and 35 °C in BM were favorable for producing highly antioxidant films with minor structural modifications
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
Study of the aging of fermented of yacon (Smallanthus sonchifolius) and sensory profile and acceptance
Consumo fermentativo di N assimilabile e sviluppo/evoluzione della componente volatile in vini bianchi ottenuti in assenza di SO2
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
Fermentation of sulphite-free white musts with added lysozyme and oenological tannins: Nitrogen consumption and biogenic amines composition of final wines
Novel vinegar-derived product enriched with dietary fiber: effect on polyphenolic profile, volatile composition and sensory analysis
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 (<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