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In this study, the influence of vibration, bottle position, and initial headspace volume on the oxygen distribution inside a wine bottle were investigated. For this purpose, a model wine was filled in 0.75 L wine bottles and stored horizontally and vertically under different vibration intensities (500 mm/s2 and 1000 mm/s2) at a constant frequency of 50 Hz. The bottles were sealed with screw cap and cork closure and two different headspace volumes for each closure type. Our results indicated, that vibration and horizontal bottle position promoted the dissolution of oxygen from the headspace of the bottle into the wine causing accelerated sulfur dioxide degradation. The effect of vibration was larger in horizontally stored bottles indicating that a larger surface promotes oxygen uptake into the wine. In absence of headspace oxygen, vibration and bottle position showed no influence on sulfur dioxide-related oxygen degradation. Furthermore, it was shown that the dissolution of oxygen was faster under cork closure than under screw cap due to the overpressure by corking process. It was concluded that vibration and horizontal bottle position have a major impact on the dissolution of headspace oxygen from the headspace of the bottle into the wine but not on the chemical reaction of the dissolved oxygen with sulfur dioxide. The larger surface between the headspace and wine in horizontally stored bottles and the overpressure created by corking process accelerates the oxygen uptake from the bottles headspace into the wine.

Over the last 20 years in the Pfalz region of Germany, GDD were highest in the vintages 2018-2020. To visualize the effect of climate change for the Pfalz region of Germany, the development of TSS and TAwere documented during Pinot noir grape ripening for the vintages 1998-2021. It was observed that climate change causes sooner and accelerated ripening, however, sooner or accelerated ripening were not connected with each other. The presented study investigated the impact of vintages on berry physiology development, ripening heterogeneity in grape clusters, changes in grape constituent concentrations and their extractability with progressing grape maturity. Pinot noir and Cabernet Sauvignon, both cultivated in the Pfalz region, were compared during three consecutive vintages. Different maturities were considered in the range of 17-25 Brix and berry size distribution was documented. The changes in grape constituent concentrations and their extractability with progressing grape maturity were analyzed using HPLC-DAD/FD, LC-QToF-MS and protein precipitation assay. It was revealed that tannin extractability differs for grape varieties and vintages and progressing maturity seemed to have only a small influence on the extractability of anthocyanins.

UV-C treatment is discussed as an effective and efficient method to inactivate harmful microorganisms in wine and other viticultural products. In comparison to other stabilisation techniques, the application of UV-C is thought to be beneficial to reduce energy costs and to minimize SO2 addition. The object of this work was to determine the lethal UV-C dose for harmful microorganisms such as Brettanomyces bruxellensis and Acetobacter aceti. The concept of 5-log inactivation was applied and the Weibull model was used to compare different microbial and wine parameters. Microbial relevant UV-C doses and 2-fold overdose treatments and how they affected chemical and sensory changes of wine were investigated. Riesling and Pinot noir wine, which have different absorbance at 254 nm, were individually inoculated with microorganisms at different inoculation numbers. The results showed that the Weibull model is appropriate to predict the lethal UV-C dose. Already at microbially relevant doses, UV-C treatment can lead to significant changes in the colour and concentration of aroma compounds in white wine. Higher concentrations of 2-aminoacetophenone were found with increasing UV-C doses. Hence, UV-C overdosing can cause the “atypical ageing” off-flavour in wine. However, microbially relevant UV-C doses change the sensory properties of wine more towards a typical ageing character.

The color of wine is an important quality parameter essential for the first impression of consumers. The International Organization of Vine and Wine (OIV) recommends two methods to describe wine color: color calculation according to Glories and the determination of coordinates in the CIE L*a*b* color space. The measurement of wine color is often not feasible for winemakers because the required instrumentation is expensive and bulky. In this study, the influence of photometer settings on the calculated color was investigated based on 14 wines. Furthermore, the CIE L*a*b* and Glories system were compared using 56 red and 56 white wines. Photometer settings were found to influence the reproducibility of color determination. In addition, CIE L*a*b* system do not correlate in all wines with the Glories system and Glories probably provides less information about wine color. Using interpolation, CIE L*a*b* coordinates were calculated from single wavelength measurements taken by a small-sized and inexpensive portable analysis system, which could be used by winemakers in the future.

Developers often prefer flexibility over upfront schema design, making semi-structured data formats such as JSON increasingly popular. Large amounts of JSON data are therefore stored and analyzed by relational database systems. In existing systems, however, JSON's lack of a fixed schema results in slow analytics. In this paper, we present JSON tiles, which, without losing the flexibility of JSON, enables relational systems to perform analytics on JSON data at native speed. JSON tiles automatically detects the most important keys and extracts them transparently - often achieving scan performance similar to columnar storage. At the same time, JSON tiles is capable of handling heterogeneous and changing data. Furthermore, we automatically collect statistics that enable the query optimizer to find good execution plans. Our experimental evaluation compares against state-of-the-art systems and research proposals and shows that our approach is both robust and efficient.

Yeast inoculation from the tops of tanks is common in white wine fermentations. Our objective was to examine whether inhomogeneities occur in tanks following yeast addition from the top with and without brief stirring after inoculation. We investigated whether inhomogeneities affect fermentation kinetics and formation of acetaldehyde, acetic acid, and pyruvate in Riesling juices with low turbidity. Samples and temperatures were taken at multiple tank heights in pilot-scale (105 L) and industrial-scale (2500 and 7000 L) tanks to investigate the distributions of temperature, yeast, and fermentation products in tanks of different volumes and height-to-diameter ratios. When the tank was not stirred following inoculation, cell counts were higher in the upper tank section for multiple days. Fermentation started earlier at the top of the tank than at lower levels, as indicated by specific gravity measurements. The top and bottom of the tanks differed by up to 8.6°C and 0.040 in specific gravity. The inhomogeneities lasted four days in the 7000 L tanks. These results suggest slow yeast sedimentation and poor mixing in the downward direction during the early fermentation phase. During vigorous fermentation, all parameters were homogenously distributed. Brief stirring after yeast inoculation provided uniform conditions during the early fermentation phase, except for temperature differences due to natural stratification. Stirring also shortened the fermentation duration. The final pyruvate concentration was significantly lower when the yeast was stirred in, presumably due to better nutrient availability throughout the tank, reducing sulfur dioxide demand. No differences were observed in acetaldehyde and acetic acid concentrations. When yeast is not stirred in following inoculation, tank sampling valves and temperature sensors do not reflect the entire tank during the early fermentation phase, which will negatively affect process control.

UV-C was investigated to inactivate microorganisms in grape must. The aim was to evaluate the effect of UV-C on wine-related yeasts under winery conditions, to investigate the toxicological potential and to analyze the effects on chemical and sensory wine properties. Metschnikowia pulcherrima showed the highest UV-C tolerance, Saccharomyces cerevisiae the lowest. With an initial cell count of 106 cfu/mL, M. pulcherrima required a UV-C dose of >1.2 kJ/L, S. cerevisiae Industrial relevance UV-C treatment is a non-thermal processing technique for the preservation of food. In this study, the applicability of UV-C treatment for the inactivation of spoilage yeast in grape must was demonstrated in pilot scale. The treatment provided sufficient microbial inactivation without having toxicological impact as examined by the Ames test and without causing off-flavor formation in the wines using relevant doses.

Background and Aims Temperature control during fermentation significantly impacts the energy demand of wineries. We determined the heat required to be dissipated from wine tanks under three different temperature programs (14, 16–11–17 and 19°C) during 1200 L Riesling fermentations and investigated the influence of temperature on yeast growth and viability, the formation of yeast derived volatiles and wine sensory properties. Methods and Results Heat dissipated by the coolant was determined using heat meters. At 19°C, ~70% less heat had to be dissipated compared to that at 14°C, whereas ~30% less heat had to be dissipated for the 16–11–17°C temperature program. The duration of fermentation was 15, 13 and 9 days for the 14, 16–11–17 and 19°C programs, respectively. Characteristic profiles of heat dissipated per day and reduction in specific gravity were observed. The formation of most esters was more pronounced in the second half of fermentation at higher temperature. Hexyl acetate, however, was formed early and no temperature influence was observed. The final concentration of ethyl decanoate, ethyl octanoate and ethyl hexanoate was greater for fermentations at 19°C, while that of ethyl butanoate was highest at 14°C. No difference was found in the final concentration of acetate esters or acetic acid. Acetaldehyde concentration was 35% lower for fermentations at 19°C, compared with those at 14°C. Descriptive analysis, at 5 and 11 months after bottling, revealed no significant difference in wine sensory profiles. Flow cytometry showed faster yeast growth, greater population size and rapid viability decline at the higher fermentation temperature. Conclusions Energy savings can be achieved by reducing the required dissipated heat through temperature management of fermentations, without compromising wine composition. Ambient temperature should be considered when deciding on temperature management and related saving potentials. Significance of the Study Potential energy savings were demonstrated that may facilitate innovation in fermentation cooling systems.

Cloud analytical databases employ a disaggregated storage model, where the elastic compute layer accesses data persisted on remote cloud storage in block-oriented columnar formats. Given the high latency and low bandwidth to remote storage and the limited size of fast local storage, caching data at the compute node is important and has resulted in a renewed interest in caching for analytics. Today, each DBMS builds its own caching solution, usually based on file-or block-level LRU. In this paper, we advocate a new architecture of a smart cache storage system called Crystal , that is co-located with compute. Crystal's clients are DBMS-specific "data sources" with push-down predicates. Similar in spirit to a DBMS, Crystal incorporates query processing and optimization components focusing on efficient caching and serving of single-table hyper-rectangles called regions. Results show that Crystal, with a small DBMS-specific data source connector, can significantly improve query latencies on unmodified Spark and Greenplum while also saving on bandwidth from remote storage.

UV-C treatment is a commonly known technique to inactivate microorganisms. The objective of this work was to investigate the impact of UV-C treatment of grape must on the sensory characteristics of the resulting wine and on the profile of volatile compounds of grape must and wine. Different UV-C doses were applied to Riesling must and compared with thermal pasteurization. The sensory off-flavor “ATA” and a content of 0.5 µg/L 2-aminoacetophenone were determined in the grape must and in the resulting wine after UV-C treatment with a high dose of 21 kJ/L. Sensory off-flavors did neither occur after thermal pasteurization nor after UV-C treatment with a dose of 2 kJ/L, which is sufficient for the inactivation of microorganisms. Minor changes in the volatiles’ profiles of grape must and wine, involving e.g. terpenes and C13-norisoprenoids, occurred in musts treated with thermal pasteurization as well as with a UV-C dose of 2 kJ/L.

One goal of wine industry logistics is to preserve wine quality during transit between winemaker and wine consumer. This study monitored temperatures during bulk shipments from Australia to Germany and investigated their impact on chemical and sensory characteristics of Chardonnay wine. The objective was to optimize scheduling and logistic conditions and determine the critical time-temperature relation for intercontinental shipments, thus minimizing unfavorable changes in chemical and sensory composition. Three intercontinental shipments were conducted between November 2015 and October 2016; each shipment lasted between 58 and 63 days and comprised six 20-foot containers holding 24,000 L of wine in flexitanks. The containers were positioned at three different locations on the vessel: on deck, below deck near the bow, and below deck further aft. Air temperature inside containers ranged from 4 to 47°C, with peak temperatures reached during daytimes in ports. Different container locations on the vessel contributed to a mean wine temperature difference of 5°C. Shipping during north- and southward equinox kept mean wine temperatures 6°C lower than shipping during June and December solstice. Decreased SO2 content and increased yellow color were observed for containers exposed to higher temperatures. Ethyl decanoate, ethyl dodecanoate, and phenylethyl acetate were lower in wine transported via container ships than in air-cargoed wines, while diethyl malate and diethyl succinate, decanoic acid, and dodecanoic acid increased as a result of the temperature impact during transportation with the container ship. Descriptive sensory analysis revealed increased honey intensity and decreased freshness when shipping scheduling and logistic conditions were associated with high temperatures. The loss of freshness was most pronounced when wine temperatures reached >25°C.

The objective was to investigate the applicability of UV-C technology to inactivate yeasts and bacteria in must and wine. Experiments were carried out in vintage 2016 with Riesling musts of different quality containing their natural microflora. Yeasts were tested more resistant to UV-C energy than bacteria. Saccharomyces cerevisiae showed higher tolerance against UV-C irradiation than Hanseniaspora uvarum facilitating new opportunities to control spontaneous fermentations. However, inactivation efficacy was strongly dependent on turbidity of musts and the initial degree of contamination suggesting a shadowing effect of individual germs. Compared with thermal pasteurization, UV-C treatment of must with 1 kJ/L showed similar effects in germ-reduction. While thermal pasteurization significantly decreased aroma precursors in musts, UV-C treatment did not change concentrations of glycosidically-bound C6-alcohols, monoterpenes and C13-norisoprenoids as shown by GC-MS analysis. Applying UV-C technology in wines, it was possible to irreversibly stop ongoing alcoholic fermentation indicating that UV-C treatment is capable to replace SO2 addition to produce wines with residual sugar. Besides inactivation power, UV-C is known for its ability to form powerful off-flavours such as methional or methanethiol. Sensory analysis revealed that the application of UV-C at doses

The polyphenols of a 2005 Cabernet Sauvignon were fractionated by gel permeation chromatography. The obtained fractions were reconstituted in a model wine medium for analysis. The chemical properties of the fractions were investigated by HPLC-DAD, HPLC-ESI-MSn, colorimetric analysis, and additional chemical assays. Application of these different techniques and combination with the elution pattern of the gel permeation material revealed some valuable structural information. The early eluting fractions, which were larger in molecular size and/or more polar than late eluting fractions, contained higher proportions of pigmented polymers and higher amounts of bound anthocyanins. These anthocyanins were responsible for the color properties of the early eluting fractions, which could be separated according to CIELab analysis. The later eluting fractions exhibited lighter, more yellowish color, provoked by the higher tannin concentration, and contained low molecular weight proanthocyanidins. Descriptive sensory analysis was carried out, assessing bitterness, sourness, and attributes describing different subqualities of astringency. Dry tannin intensity was rated lower for the early eluting anthocyanin-rich polymers compared to the later eluting fractions, which were rich in procyanidins and/or oligomerized flavan-3-ols. Accordingly, the attenuation of the astringent perception, as it is generally observed during red wine aging, may be attributed to increasing anthocyanin incorporation into the polymers. In contrast to astringency, the intensity of bitterness was not sufficiently correlated with any chemical parameter. This observation suggests that very specific phenolic structures are responsible for the bitter perception in red wines. As the high molecular pigmented polymers evoked lowest astringency ratings, the results of this study indicate that the increase of astringency due to higher degrees of polymerization can be substantially prevailed by the incorporation of anthocyanins into polymeric structures.

Dissolved and headspace oxygen concentrations were monitored during microoxygenation (MOX) treatments before and after malolactic fermentation (MLF) of Pinot noir. The implementation of a noninvasive, fluorescence-based measurement system allowed precise oxygen determination in red wine and in the gaseous headspace above the wine surface. Dissolved oxygen (DO) concentrations increased up to 1 and 0.5 mg/L in the second half of pre-MLF and post-MLF MOX experiments, respectively. Untreated control wines showed maximum DO concentrations of only 0.1 mg/L at the end of the pre-MLF and post-MLF MOX trials. For both pre- and post-MLF MOX experiments, the measurement of DO was sufficiently sensitive to discriminate between untreated control and oxygenated wines. Furthermore, different levels of applied oxygen dosages could be differentiated using DO monitoring. Except for the end of post-MLF MOX treatments with high oxygen dosage, no DO gradients were observed within the tanks, suggesting appropriate oxygen distribution during the treatment periods. The novel concept to compare the rate of applied oxygen with DO lead to the expression of the oxygen consumption rate. Plotting this parameter together with the applied oxygen dosage allowed for the assessment of the balance between the ingress and the consumption of oxygen. During pre-MLF and post-MLF MOX treatments, the oxygen consumption rate was consistently ±10% of the applied oxygen dosage. However, wines receiving oxygen post-MLF reacted more sensitively to an elevated oxygen dosage than those treated pre-MLF.

Different microoxygenation procedures before and after malolactic fermentation were applied to Pinot noir wines from two consecutive vintages using the same Pinot noir block and a standardized winemaking protocol. The effects of microoxygenation treatments were investigated by spectrophotometry, HPLC-DAD, and descriptive sensory analysis. Microoxygenation before malolactic fermentation was carried out in 250-L red wine fermentors at oxygen dosages of 20 and 100 mg/L/month for 20 days. Oxygen dosages of 1 and 5 mg/L/month were applied for three months after malolactic fermentation using 100-L stainless-steel tanks. CIELab results showed that microoxygenation in 2006 tended to yield light-colored wines with an increase in yellow tonality. Examining monomeric polyphenols after alcoholic fermentation, this oxygen-induced color loss may be related to the high flavan-3-ol to anthocyanin ratio in this vintage. Furthermore, twice the increase in acetaldehyde content upon microoxygenation after malolactic fermentation was observed in 2006, which indicated excess oxygen for these wines. By contrast, a low flavan-3-ol to anthocyanin ratio was determined after alcoholic fermentation in wines of vintage 2007. Predominantly, these wines showed an increase in blueness upon microoxygenation treatments. Low correlations among astringency related attributes proved that the chosen attributes independently characterized the sensory variation in tannic structure among the microoxygenated Pinot noir wines. Descriptive analysis revealed that microoxygenation predominantly diminished green tannins in 2006 wines. Dry tannins, although decreasing in course of microoxygenation with low oxygen doses, rose again at higher oxygen doses. Beneficial aroma changes in 2006 and the increase of color intensity in 2007 were more salient upon microoxygenation prior to malolactic fermentation. An unfavorable impact on Pinot noir aroma occurred primarily due to microoxygenation after malolactic fermentation.

The present study evaluates the influence of pyranoanthocyanins on the color of German red wines (Dornfelder, Cabernet Sauvignon, and Pinot Noir) from different vintages from 1996 to 2006. The wines were spiked with a solution of pinotin A raising the natural pyranoanthocyanin concentration in the wine by 2, 5, 8, 10, and 15 mg/L. The color parameters were determined by spectroscopy and the spiked wines were presented to a sensory panel in a 3-alternative forced choice (3-AFC) test for color evaluation. The comparison of treated and untreated wines clearly demonstrated that the influence of pinotin A on the overall perceived color in these red wines was not significant. The 3-AFC test showed no significant difference between Dornfelder and Cabernet Sauvignon wines, due to the increase of pinotin A. Solely in the case of some aged Pinot Noir wines small effects (i.e., strong decrease of lightness and low decrease of chromaticity) were apparent, which could be shown to be due to the dilution of the sample caused by the added pinotin A solution.

The impact of the addition of ascorbic acid, sulfur dioxide and glutathione on oxidation product formation under accelerated oxidative conditions was evaluated in model wines. The effects of these antioxidants have been compared in aqueous ethanol solutions containing (+)-catechin and metal ions at pH 3.2 by monitoring O2 consumption, color evolution by CIELab, as well as (+)-catechin and glutathione decrease by LC-DAD/FD. The analysis of oxidation products formation was focused on the determination of yellowish colored xanthylium compounds by LC-ESI-ToFMS and acetaldehyde by HS-GC-FID. The results could show, that under some conditions glutathione could not inhibit carboxymethine-briged (+)-catechine dimer formation and subsequent xanthylium cation pigment generation, compared to ascorbic acid or sulfur dioxide addition providing a good protec- tion against oxidative color changes. In systems containing 0.08–0.32 mmol/L glutathion without any further addition of SO2 or ascorbic acid, increasing acetaldehyde concentrations could be observed. These results demonstrate clearly the need for further research to highlight the reactions of glutathione.

Microoxygenation (MOX) is a widely applied technique to deliver continuously trace amounts of oxygen to red wine during vinification and ageing in order to improve color stability and sensory properties. Proven by sensory means, the added oxygen modifies not only tannin structure and color of the wines, but also their composition of volatiles. In this study different microoxygenation treatments prior and after malolactic fermentation were carried out for Pinot noir, Cabernet Sauvignon and Dornfelder wines of the 2007 vintage. Volatile components of subsequent wines were analyzed using headspace-solid phase microextraction coupled to comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry (GC x GC-qMS). Quantitative data were retrieved from two-dimensional images obtained from GC x GC chromatograms of volatile compounds applying a software package, which is commonly used in the field of proteomics for two-dimensional electrophoresis gels. This approach revealed a discrimination of the applied treatments by multivariate statistics based on volatiles alone, such as the clear distinction among wines treated before or after malolactic fermentation in case of Cabernet Sauvignon and Dornfelder or the effect of different oxygen doses. Besides the differentiation of MOX treatments from the untreated control, specific varietal and technological effects could be distinguished. The image processing of the GC x GC data offered valuable tools which were able to identify those areas in the 2D images that were most responsible for discrimination among different MOX treatments. Based on the loadings of individual aroma compounds a set of markers for the MOX-induced modifications of volatiles could be suggested.

Concurrency control is one of the most performance critical steps in modern many-core database systems. Achieving higher throughput on multi-socket servers is difficult and many concurrency control algorithms reduce the amount of accepted schedules in favor of transaction throughput or relax the isolation level which introduces unwanted anomalies. Both approaches lead to unexpected transaction behavior that is difficult to understand by the database users. We introduce a novel multi-version concurrency protocol that achieves high performance while reducing the number of aborted schedules to a minimum and providing the best isolation level. Our approach leverages the idea of a graph-based scheduler that uses the concept of conflict graphs. As conflict serializable histories can be represented by acyclic conflict graphs, our scheduler maintains the conflict graph and allows all transactions that keep the graph acyclic. All conflict serializable schedules can be accepted by such a graph-based algorithm due to the conflict graph theorem. Hence, only transaction schedules that truly violate the serializability constraints need to abort. Our developed approach is able to accept the useful intersection of commit order preserving conflict serializable (COCSR) and recoverable (RC) schedules which are the two most desirable classes in terms of correctness and user experience. We show experimentally that our graph-based scheduler has very competitive throughput in pure transactional workloads while providing fewer aborts and improved user experience. Our multi-version extension helps to efficiently perform long-running read transactions on the same up-to-date database. Moreover, our graph-based scheduler can outperform the competitors on mixed workloads.