294 research outputs found
Flint glass bottles cause white wine aroma identity degradation
Due to marketing recommendations, white wines are often bottled in flint glass to improve aesthetics and showcase wine color. Although this practice is known to cause a wine fault, the influence of light on the fruity and flowery aromatic profile of wine is unknown. The aim of this study was to investigate the changes to the white wine volatilome under typical supermarket shelf conditions, using 1,052 bottles of 24 white wines. After only 7 d of shelf life in flint glass bottles, a dramatic loss in terpenes (10 to 30%) and norisoprenoids (30 to 70%) was recorded, whereas colored glass bottles did not evidence such behavior even after 50 d, and darkness preserved the wine’s fruity and flowery aromatic integrity. We also proposed an alternative mechanism for the insurgence of the lightstrike off-odor, which takes the varietal aroma loss into account. In light of this understanding of the flint glass negative impact on white wine aroma identity and sensorial character, this packaging should be strongly discouraged. The same findings should be valid for a wide range of several daily consumed foodstuff where transparent packaging is use
On sample preparation methods for fermented beverage VOCs profiling by GCxGC-TOFMS
Introduction
Aromas and tastes have crucial influences on the quality of fermented beverages. The determination of aromatic compounds requires global non-targeted profiling of the volatile organic compounds (VOCs) in the beverages. However, experimental VOC profiling result depends on the chosen VOC collection method.
Objectives
This study aims to observe the impact of using different sample preparation techniques [dynamic headspace (DHS), vortex-assisted liquid–liquid microextraction (VALLME), multiple stir bar sorptive extraction (mSBSE), solid phase extraction (SPE), and solid phase micro-extraction (SPME)] to figure out the most suitable sample preparation protocol for profiling the VOCs from fermented beverages.
Methods
Five common sample preparation methods were studied with beer, cider, red wine, and white wine samples. After the sample preparation, collected VOCs were analyzed by two-dimensional gas chromatography coupled with time of flight mass spectrometry (GCxGC-TOFMS).
Results
GCxGC oven parameters can be optimized with the Box–Behnken surface response model and response measure on peak dispersion. Due to the unavoidable column and detector saturation during metabolomic analysis, errors may happen during mass spectrum construction. Profiling results obtained with different sample preparation methods show considerable variance. Common findings occupy a small fraction of total annotated VOCs. For known fermentative aromas, best coverage can be reached by using SPME together with SPE for beer, and VALLME for wine and cider.
Conclusions
GCxGC-TOFMS is a promising tool for non-targeted profiling on VOCs from fermented beverages. However, a proper data processing protocol is lacking for metabolomic analysis. Each sample preparation method has a specific profiling spectrum on VOC profiling. The coverage of the VOC metabolome can be improved by combining complementary methods
Vitis vinifera - a chemotaxonomic approach: Anthocyanins in the skin
The gaining of new knowledge about varietal differences in grapevines can be useful for the designing of genetic improvement programs. More and more, chemical methods complement ampelographic ones in the study of variability in grapevines. This work is aimed at the anthocyanin profiling of red-coloured grapes, of which ca. 120 cultivars were sampled; among these there were a high number of old Italian vines and 30 Vitis vinifera ssp. silvestris originating from different areas of Italy. Anthocyanins were HPLC separated and quantified with the aid of an inverse phase microbore column and a photodiode detector. Grapevines were numerically separated in groups using as indexes the percentage of the 5 monoglucosides present, the summations of: acetic esters; malvidin-3-monoglucoside-caffeoate plus all 5 p-coumaric esters; as well as a series of relations correlated to certain enzymatic activities necessary for the esterification of glucosides, hydroxylation and methylation in the biosynthesis of several anthocyanins. Data derived from the study of indexes of varietal enzymatic activity enable us to qualify differences between grapevines linked to the synthesis of anthocyanins. The stability of anthocyanic profiles within the same grape variety enables the use of this technique for taxonomic purposes. This research study discusses the use of this technique for classification and analysis of grape phylogenesis. An in-depth look into the relations between cultivated and wild varieties is given
Identification of two stilbenoids from Vitis roots
Two oligostilbenes were isolated from roots of Vitis vinifera cv. Chardonnay and their structures were identified. One compound, ampelopsin A, is a dimer of resveratrol and has been found previously only in the roots of Ampelopsis brevipedunculata var. hancei (Vitaceae). The second, hopeaphenol, can be regarded as a dimer of ampelopsin A; its presence in Vitaceae is reported here for the first time. Both compounds are present in mg per g levels in vine roots
Exploring multisensory interactions through the study of astringency diversity of mono-varietal italian red wines.
Economics of One Health: Costs and benefits of integrated West Nile virus surveillance in Emilia-Romagna
Since 2013 in Emilia-Romagna, Italy, surveillance information generated in the public health and in the animal health sectors has been shared and used to guide public health interventions to mitigate the risk of West Nile virus (WNV) transmission via blood transfusion. The objective of the current study was to identify and estimate the costs and benefits associated with this One Health surveillance approach, and to compare it to an approach that does not integrate animal health information in blood donations safety policy (uni-sectoral scenario). Costs of human, animal, and entomological surveillance, sharing of information, and triggered interventions were estimated. Benefits were quantified as the averted costs of potential human cases of WNV neuroinvasive disease associated to infected blood transfusion. In the 2009–2015 period, the One Health approach was estimated to represent a cost saving of €160,921 compared to the uni-sectoral scenario. Blood donation screening was the main cost for both scenarios. The One Health approach further allowed savings of €1.21 million in terms of avoided tests on blood units. Benefits of the One Health approach due to short-term costs of hospitalization and compensation for transfusion-associated disease potentially avoided, were estimated to range from €0 to €2.98 million according to the probability of developing WNV neuroinvasive disease after receiving an infected blood transfusion
Vitis vinifera - a chemotaxonomic approach: Seed storage proteins
The IEF pattern of the constituent peptides for the storage protein from Viris vinifera endosperm is used for the construction of a dendrogram relating 74 seed specimens
Economics of One Health: Evidence of substantial benefits of integrated West Nile virus surveillance
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