Months In Bottle Research Articles

The effect of pasteurisation and storage on aroma compounds in lager

Why was the work done: To investigate the impact of pasteurisation and storage in bottle on aroma compounds in pale lager beer. How was the work done: Pale lager beer was produced at an industrial scale with 100% pilsner malt and a bottom fermenting yeast. Samples were taken of unpasteurised beer from bright beer tank, after flash pasteurisation and six months after packaging in amber glass bottles. What are the main findings: Post pasteurisation, a marked increase was found in the concentration of 2,3-pentanedione (50%) and diacetyl (33%), presumably reflecting the decomposition by heat of precurser acetohydroxy acids. There was also a marginal increase in dimethyl sulphide (6%) with little or no change in other aroma compounds. Storage for six months in bottle, also resulted in an increase in the level of 2,3-pentanedione, diacetyl and dimethyl sulphide. The linear (Pearson) correlation was > 0.8 for both dimethyl sulphide and diacetyl, and 2,3-pentanedione and diacetyl. Accordingly, it was concluded that the levels in beer of dimethyl sulphide and 2,3-pentanedione are proportionally related to diacetyl. Why is the work important: This work provides an insight into the effects on flavour and aroma of lager of flash pasteurisation and subsequent storage in bottle. The inter-relationship between aroma compounds in beer suggests that such synergies may undermine the sensory perception of threshold levels and identification of specific aromas.

Use of AirMixing M.I.® resonance waves to produce aroma richer Sangiovese wine without sulphites addition in a sustainable way

In recent years, wine without sulphite addition has grown increasingly popular. In this work, resonance waves (AirMixing M.I.®) were applied to Sangiovese must in fermentation to produce wine without sulphite addition, monitoring the fermentation kinetics and analyzing polyphenols and volatile organic compounds (VOCs) extraction. Resonance waves were created by injecting compressed air into a 10 hL stainless steel tank filled with Sangiovese must, without pumping-over/delestage, and no sulphites in all the process (AM). Control wine was produced using pumping-over/delestage and adding sulphur dioxide. After 4 months in bottles, simulating the commercial habit used to sell in spring the last year wine, volatile acidity was significantly lower in AM wine, while total anthocyanins, trans-resveratrol and free quercetin were significantly higher. Among free (VOCs), the classes of terpenes and benzenoids were significantly higher in the Control wine while the classes of aldehydes, alcohols, volatile phenols, lactones and pyrazine were in the AM wine. Unlike free VOCs, in glycosylated VOCs, terpenes and benzenoids were significantly higher in AM wine. In conclusion, resonance waves permit to speed up the fermentation increasing phenols extraction and producing wines with excellent maintenance of VOCs, requiring less energy and labor, and thus being more economically and environmentally sustainable.

Identification and structural characterization of a novel (+)-catechin-caffeic acid adduct present in wines

A new compound with a molecular ion mass of m/z 467 in the negative ion mode was found to occur in a white wine aged 30 months in bottle. In this latter, fragment ions compatible with the loss of a carboxylic acid (-44 a.m.u.), a caffeic acid unit (-178 a.m.u.), and a Retro-Diels Alder (-152 a.m.u.) were observed. The present work reports the synthesis of a (+)-catechin-caffeic acid adduct resulting from the condensation reaction between caffeic acid and (+)-catechin. The structural characterization by NMR showed that this adduct is formed by the linkage between carbon 8 at ring A from (+)-catechin and carbon 9 from caffeic acid. In addition, the similarity in the HPLC retention time and UV–Visible spectra of the synthesized compound with the one detected in white wine and the bottling experiments, confirms the presence of this novel (+)-catechin-derived compound in those matrices.

Volatile profile of two monovarietal white wines under different antioxidant environments during storage in bottle

The volatile organic compounds (VOCs) formed during winemaking can be modulated by several additives, namely by the use of sulphur dioxide (SO2) which has been well-accepted on winemaking as a preservative agent. However, some drawbacks associated with SO2wine application led to the need to reduce or replace its use. In this work, VOCs profile after storage in bottle under different antioxidant conditions of two Portuguese monovarietal wines (‘Arinto’ and ‘Síria’) was studied. Wines were obtained by different winemaking environments (0, 50, 100 mg/L of SO2and 100 mg/L ascorbic acid for ‘Síria’ and 15, 30, 45 mg/L of SO2and 100 mg/L of ascorbic acid for ‘Arinto’ both with and without bentonite). After alcoholic fermentation, a second SO2treatment was applied: 0 and 60 mg/L of SO2to ‘Arinto’ wines and 30 and 60 mg/L of SO2to ‘Síria’ wines. Wines were kept over lees for three months, bottled and analysed after three months in bottle. The VOCs present were analysed by HS-SPME-GC/MS six months after fermentation. The maturation conditions did not influence the evolution of free and total SO2. Regarding the VOCs profile evolution, the ANOVA analysis showed that esters are the most important group, presenting significant differences among samples. Through the PCA analysis, using wines after fermentation as reference, 74.13 % and 54.92 % of the variation were explained by the first two principal components for ‘Arinto’ and ‘Síria’, respectively. VOCs profile evolution of wines seems to be mainly influenced by the fermentation conditions.

Characterization of Brazilian Syrah winter wines at bottling and after ageing

ABSTRACT: Double pruning extended the harvest season of wine grape (Vitis vinifera L.) to dry winter, enabling production of high quality wines in the southeastern Brazil. Winter harvest allows grapes to fulfill not only technological maturation, but also phenolic ripeness. Winter wines from Syrah grapes harvested from eight vineyards in southeastern Brazil during three harvests were analyzed for their chemical and aromatic composition after bottling and after ageing for 20, 30, and 42 months in bottle. Winter wines have high content of total phenolic compounds, which remained almost constant through ageing, as well as color intensity. Malvidin 3-O-glucoside stood out among anthocyanins, remaining 5-10 % after 39 months of ageing. Moreover, malvidin 3-O-glucoside-pyruvic acid was the main pyranoanthocyanin identified in winter wine. Polymerized pigments index ranged from 54 % at bottling to 80 % after 42 months of ageing. Young winter wines are rich in ester and monoterpene, as well as alcoholic volatile compounds responsible for ethereal, fruity, flowery, fresh and sweet aromas. Aged winter wines showed higher contents of furfural, geranyl ethyl ether, isoamyl decanoate, α-muurolene and α-calacorene, contributing to sweet, fruity and woody aromas. Syrah winter wines are characterized by high content of phenolic compounds and color stability, and keep good sensorial characteristics after ageing in bottle.

Impact of Sewage Sludge Leaching on Soil Constituents and Quality

Activated sludge treatment plants generate large quantities of sludge each year, thereby posing a serious environmental problem. This study aims to experimentally assess the effect of rainwater on the leaching of sludge components. In this context, a percolation test was set up, and composed of PVC cylinders into which the solid substrate was introduced. Five modalities of the solid substrate were used: a sludge modality, a soil modality and three modalities with increasing percentage of sludge (1%, 5% and 25%) in the soil. The percolation water is collected during the rainy months in bottles placed below each column. Solid substrate samples were taken before the test and after one year. The physicochemical analysis of the percolation water showed an increase in the electrical conductivity, BOD5, COD, nitrogen compounds and phosphate compounds which were proportional to the percentage of sludge. The pH of the sewage sludge leachates varies from 7.61 to 7.98. Zinc and copper were the most mobilized metals. A year following the installation of the percolation test, electrical conductivity, total phosphorus (TP) and orthophosphate (PO4) contents decreased for the solid substrates using the five modalities. Furthermore, ammonium (NH4) and nitrates (NO3) levels decreased in soil mixed with 1 to 25% of sludge due to their leaching by rainwater. Collectively, these data show that the leachates through the soil mixed with sludge are stable and loaded with NO3, a plant nutrient that can contaminate the groundwater as well as the surface waters inducing their eutrophication. Furthermore, addition of sludge to the soil improves the levels of carbon, total nitrogen, TP and PO4 in the soil and thereby soil fertility. The addition of sludge, however, is not without soil contamination with heavy metals. Such soil contamination would cause pollution of surface and ground water. Reaching certain severity, it should call for the adoption of prompt measures for the protection of environment and human health.

Phenolic and Aroma Changes of Red and White Wines during Aging Induced by High Hydrostatic Pressure.

The aim of this study was to investigate use of high hydrostatic pressure (HHP) along with different antioxidants (glutathione and SO2) as an alternative method for wine preservation and production of low-SO2 wines. In the first phase of the study, low-SO2, young red and white wines were pressurized at three pressure levels (200, 400 and 600 MPa) for 5, 15 and 25 min at room temperature, and analyzed immediately after treatments. Additionally, for the wine aging experiment, red and white wines with standard-SO2, low-SO2+glutathione and low-SO2 content were treated with HHP treatment (200 MPa/5 min) and stored for 12 months in bottles. Color parameters, phenolic and aroma compounds were determined. The sensory evaluation was also conducted. HHP showed very slight, but statistically significant changes in the chemical composition of both red and white wine right after the treatment, and the main variations observed were related to the different pressures applied. Furthermore, during aging, most of the differences observed in chemical composition of pressurized wines, both red and white, were statistically significant, and greater in wines with a lower content of antioxidants. However, after 12 months of aging, some differences between unpressurized and pressurized samples with standard SO2 content were lost, primarily in aroma compounds for red wine and in color and phenolics for white wine. Additionally, similar values were obtained for mentioned characteristics of red and white wines in pressurized samples with standard SO2 and low SO2+glutathione, indicating that HHP in combination with glutathione and lower doses of SO2 might potentially preserve wine. The sensory analysis confirmed less pronounced changes in the sensory attributes of pressurized wines with higher concentration of antioxidants. Furthermore, the treatments applied had a slightly higher effect on the sensory properties of white wine.

Detailed chemical composition of Cabernet Sauvignon wines aged in French oak barrels coopered with three different stave bending techniques

Cabernet Sauvignon wines were aged for 15 months in used and new French 225 L oak barrels, followed by a period of 3 months in bottle. In addition to control barrels (3 years old), three bending/toasting protocols, including fire bent and fire toasted (fire-bent); water bent and fire toasted (water-bent); and a hybridized method based on fire bending and toasting followed by a 12 h fill with water at 80 °C (fire-bent + hot water), were trialed in triplicate. Parameters such as acetic acid and alcohol content (higher in control wines), and anthocyanins, color and polymeric pigments (higher in wines aged in the new barrels), were more affected by barrel use (new versus neutral) than by bending/toasting protocols. At the end of the study (day 602), only 4-vinyl-guaiacol, eugenol and cis-lactone showed odor activity values (OAV’s) above 1, with the latter being the most relevant odor active compound across treatments whereas eugenol was 10-fold higher in the water-bent wines. Principal component analysis (PCA) including phenolics and volatile compounds suggested differences between wines aged in control and new barrels, but less clear-cut differences within wines aged in barrels produced with the different bending/toasting protocols.

Combined Use of Pectolytic Enzymes and Ultrasounds for Improving the Extraction of Phenolic Compounds During Vinification

Phenolic compounds provide important quality attributes to red wines. These compounds are found inside the vacuoles of the plant cells of the skin and seeds of the grape. During maceration, they diffuse to the must/wine, although for this to happen, the vegetal cell walls need to rupture. Pectolytic enzymes and high-power ultrasound (US) may facilitate this objective. Therefore, this study analyzes the extraction efficiency of phenolic compounds using pectolytic enzymes and US (applied at 2 different times of the maceration period) alone and in combination. The chromatic characteristics of the wines were analyzed by spectrophotometry and chromatography at the end of the alcoholic fermentation and after 3 months in bottle. The treatment with enzymes alone increased the concentration of tannins by 13%, but US increased both the extraction of anthocyanins and tannins (7 and 16% respectively). The combination of enzymes and US, both applied at the beginning of the maceration time, did not improve the results of the treatments separately. However, when the enzyme was allowed to act alone during the first days of maceration before US was applied, a statistically significant synergistic effect was observed, increasing the color intensity by 18% and total phenol content by 21%, and especially marked was the effect on tannin extraction, whose concentration increased in the wines by 30% at the end of alcoholic fermentation.

Application of high‐power ultrasounds during red wine vinification

SummaryWine colour is one of the main organoleptic characteristics influencing its quality. It is of special interest in red vinifications due to the economic resources that wineries have to invest for the extraction of the phenolic compounds responsible for wine colour, compounds that are mainly located inside the skin cell vacuoles, where the volatile compounds are also found. The transfer of phenolic compounds from grapes to must during vinification is closely related to the type of grapes and the winemaking technique. During traditional winemaking, grapes are crushed and skin macerated for several days, with pumps overs to facilitate the colour extraction. To increase this extraction, some chemical (maceration enzymes) or physical technologies (thermovinification, cryomaceration, flash‐expansion) can be applied. In this work, a new methodology has been tested. This methodology consists in the application of high‐power ultrasounds to crushed grapes to increase the extraction of phenolic compounds. Crushed grapes were treated with this non‐thermal technology and vinified, with 3, 6 and 8 days of skin maceration time, and the results were compared with a control vinification, where crushed grapes were not subjected to any treatment and were skin macerated during 8 days. The wine chromatic characteristics (determined spectrophotometrically) and the individual phenolic compounds (anthocyanins and tannins, determined by HPLC) were followed during the maceration period, at the end of alcoholic fermentation and after two months in bottle. Also, the wine volatile compounds were determined by GC‐MS. The wines made with ultrasound‐treated grapes showed differences with the control wine, especially regarding total phenol content and tannin content. The wines elaborated with sonicated grapes and with only three days of skin maceration time presented similar concentration of anthocyanins and twice the concentration of tannins than control wines elaborated with 8 days of skin maceration.

Sensory and Chemical Effects of Cross-Flow Filtration on White and Red Wines

Cross-flow filtration is an increasingly common postfermentation process in the wine industry. Our hypothesis was that cross-flow filtration would not have a significant impact on the sensory or chemical properties of white or red wines because of the nature of the membranes used in this process. To investigate this, a California white wine blend and a California red wine blend were filtered in three 570 L lots using a Bucher Vaslin cross-flow unit with a nominal 0.22-micron polyethersulfone membrane. The unfiltered control was sent directly to the bottling line without filtration. Panelists evaluated the wines nine times during an eight-month descriptive analysis panel with replicated tasting at each time point. UV-vis spectrophotometry and the Adams–Harbertson assay were used to determine color and phenolic content of the filtered and unfiltered wines, respectively. The effect of filtration was significant for one sensory attribute out of 16 total measured in the white wine. Similar analysis indicated that six sensory attributes were significantly different out of 16 total in the red wine. Unfiltered red wines were higher in earthy, grassy, oak, and smoke aromas compared to filtered wines and lower in mixed berry and stone fruit aromas compared to the filtered wines, but only after two months in bottle. Cross-flow filtration was found to have a stabilizing effect on the sensory profile of both wines. For both wines there were significant changes in color and phenolic profile with filtration, but it is not clear, especially for red wines, whether the changes in phenolic compound concentration were great enough to be detected sensorially.

Effect of alternative techniques to ageing on lees and use of non-toasted oak chips in alcoholic fermentation on the aromatic composition of red wine

The aim of this work was to evaluate the effect of different enological treatments on the volatile composition of red wine: ageing on lees with and without adding β-glucanase enzymes; the use of a commercial yeast derivative with and without β-glucanase enzymes; and the use of non-toasted chips in fermentation. The results indicated that the presence of chips during the fermentation enhanced the formation of 2-phenylethanol, ethyl esters and fusel alcohol acetates, but affected the levels of some of the lactones and volatile phenols studied negatively. In addition, it was found that wine lees and commercial yeast derivatives can bind some of the volatile compounds studied, mainly ethyl esters and fusel alcohol acetates. After 6 months in bottle, in general, the differences found between the control wine and wines fermented with chips were maintained. However, between the control wine and the wines treated with natural or commercial yeast, the differences disappeared, although not for all the compounds studied. Finally, an important effect of the addition of β-glucanase enzymes was not observed.

Colour and pigment composition of red wines obtained from co-maceration of Tempranillo and Graciano varieties

The Vitis vinifera L. cv Graciano is often used as an integral component of Rioja wines because it is considered to contribute significantly to the quality of Tempranillo based wines. The aim of this work was to determine the effect of the incorporation of the Graciano variety on the colour and pigment composition of Tempranillo based wine and to evaluate the possible differences between blending Tempranillo with Graciano varietal wine ( W wine) in contrast to a wine obtained by mixing these two grape varieties in the prefermentative maceration step ( M wine). Results indicated that pigment extraction and retention in M wine was higher than in Tempranillo ( T) wine. Colour differences ( Δ E ab * ) between wines at the end of the study (after 12 months in bottles) were detectable by the human eye ( Δ E ab * ≥ 3) in all cases except for T and W. These wines have indistinguishable colours even when using analytical methods ( Δ E ab * ≤ 1). Regarding hue h ab, T and W presented higher values (more orange-red) than Graciano ( G) and M (more blue-red). PCA allowed the colour and composition analytical data to be reduced to a small number of principal components that could separate successfully between T and G wines and between the different steps of the winemaking process.

Effect of principal polyphenolic components in relation to antioxidant activity in conventional and organic red wines during storage

Wine phenolic composition depends on the grapes used to make the wine and on the vinification conditions and a wide range of variables such as cultivar, viticulture practices and vinification techniques can affect the phenolic composition of red wines. Changes in polyphenol content and antioxidant activity during storage over 6 months in bottles were studied in Monastrell varietal red wines from grapes obtained by organic and conventional agricultural practices. Also it was studied the relationship between antioxidant activity and phenolic compounds. The results showed that the contents of anthocyanins decreased during storage although hydroxycinnamics derivatives, stilbenes and flavonols do not suffer significative changes. The total antioxidant activity of conventional and organic wines was well correlated especially with anthocyanins at first month of storage and flavonols all time. Stilbenes had a high correlation with antioxidant activity in both types of wine especially in the last month of storage (r 2 = 0.74), and hydroxycinnamic derivatives had a poor correlation with antioxidant activity. Evolution of phenolics compounds and antioxidant activity in conventional and organic wines were similar during storage. Not significant differences were observed in conventional and organic wines.

Changes in phenolic composition and antioxidant activity of white wine during bottle storage: Accelerated browning test versus bottle storage

Polyphenol content, antioxidant activity, reducing power, colour and changes during storage over nine months in bottles and after accelerated browning were studied in selected Hellenic varietal white wines. The following phenolic compounds were identified in the wines: Caftaric, coutaric, fertaric, ferulic, caffeic, p-coumaric and gallic acids, (+)-catechin and (−)-epicatechin. The results showed that the contents of most of the phenols diminished with time, with the exception of caffeic, ferulic and p-coumaric acids. Antioxidant activity increased with storage whereas reducing power remained significantly unaffected. Accelerated browning did not significantly alter the concentrations of tartaric acid esters but it increased the concentrations of the hydroxycinnamic and gallic acids. (+)-Catechin concentration was not affected while (−)-epicatechin decreased. Antioxidant activity did not show any significant change but reducing power was reduced after the end of the browning test. As for the absorbance at 420 nm, it remained unchanged during storage, but it was significantly increased after accelerated browning.

Consideration of the influence of aging process, type of wine and oenological classic parameters on the levels of wood volatile compounds present in red wines

The contents of the volatile compounds extracted from wood: cis- and trans-whiskylactones, vanillin, syringaldehyde, furfural, 5-methylfurfural, eugenol, guaiacol, p-ethyl-phenol and p-ethylguaicol have been studied in 12 single-variety wines aged in new American oak barrels. The concentration of these compounds were determined after the following combinations of time in wood and time in bottle: 0 months in wood plus 18 months in bottle, 4 months in wood + 14 months in bottle, 9 months in wood + 9 moths in bottle and 12 months in wood + 6 months in bottle. According to the composition of the wines, it is possible to conclude in general, that, the extraction of these compounds was faster during the first four or 9 months of aging in wood, depending on the wines. After 12 months of oak maturation, the extraction of these compounds slowed down. Furthermore, the final concentrations of these volatile compounds were different among studied wines. These differences could be related to some of the values of some of their oenological parameters, such as the contents of tartaric acid and sulphur dioxide of each wine.

Influence of wood origin in the polyphenolic composition of a Spanish red wine aging in bottle, after storage in barrels of Spanish, French and American oak wood

In this paper, the changes in the composition of a red wine obtained from Tempranillo grapes (Vitis vinifera L.), stored from 12 to 24 months in bottles were studied. The wine was previously aging for 21 months in barrels made of Spanish oak wood (Quercus spp.). The changes of chromatic data, global polyphenolic families assessment (polyphenols, catechins, proanthocyanidins and anthocyanins) and individually polyphenols by HPLC during their storage time in bottles were studied and compared with these of the same wine aged in barrels made of French oak and American oak and stored in bottle for 24 months. Samples of wines obtained after 12 months in bottle were also compared with those after 24 months. The stepwise discriminant analysis with data of chromatic parameters and global polyphenolic families indicates that the wines aged in Spanish and French oak wood barrels, after 24 months stored in bottle, have similar characteristics, but they are significantly different to those of wines aged in barrels made of American oak wood. Regarding the analysis of individually non-anthocyanic polyphenols, discriminant analysis shows that wines stored for 24 months in bottle, aged in barrels made of Spanish, French and American oak woods, show overlapping results, while those from wines after 12 months in bottle are more dispersed. The discriminant analysis carried out on anthocyanidin concentrations of wines stored 24 months in bottles has shown three groups according the kind of wood used, indicating that wines aged in Spanish and French oak barrels are much more similar in anthocyanidin concentrations than those aged in the American barrels.

Changes in wine volatile compounds of varietal wines during ageing in wood barrels

Twelve single-variety wines were aged in new American oak barrels. A control wine of each variety without ageing in wood was also studied. The volatile aroma composition of these wines was analysed after the following combinations of time in wood and time in bottle: 0 months in wood plus 18 months in bottle, 4 months in wood plus 14 months in bottle, 9 months in wood plus 12 months in barrel and 12 months in barrel plus 6 months in bottle. The data obtained were studied by two different multivariate methods: factor analysis by principal components and stepwise linear discriminant analysis. The results obtained showed that the capacity of wine to extract the volatile compounds from the wood depended on the variety of grape used. Furthermore, it was also found that the changes in the volatile composition of the wines induced by the wood ageing were more important during the first 4 months. In addition, the volatile compounds studied allowed to differentiate and correctly classify the wines according to the time they had been in contact with the wood.

Changes in wine volatile compounds of varietal wines during ageing in wood barrels

Abstract Twelve single-variety wines were aged in new American oak barrels. A control wine of each variety without ageing in wood was also studied. The volatile aroma composition of these wines was analysed after the following combinations of time in wood and time in bottle: 0 months in wood plus 18 months in bottle, 4 months in wood plus 14 months in bottle, 9 months in wood plus 12 months in barrel and 12 months in barrel plus 6 months in bottle. The data obtained were studied by two different multivariate methods: factor analysis by principal components and stepwise linear discriminant analysis. The results obtained showed that the capacity of wine to extract the volatile compounds from the wood depended on the variety of grape used. Furthermore, it was also found that the changes in the volatile composition of the wines induced by the wood ageing were more important during the first 4 months. In addition, the volatile compounds studied allowed to differentiate and correctly classify the wines according to the time they had been in contact with the wood.