Summary
Pinot noir wines were made with inclusion of different amount of whole bunches or grape stems: destemmed grapes only (DS), 30% whole bunch (WB30), 60% whole bunch (WB60), 100% whole bunch ...(WB100), and destemmed grapes with 100% stems added back (DS100). Wines were analysed using modified Somers assay and CIELab method at the end of fermentation and after a 2 years bottle ageing. CIELab analysis showed that DS100 was significantly different from all other treatments at both sampling points, and whole bunch addition treatments (except of WB30) only showed significant colour difference compared to DS treatment after bottle ageing. Total anthocyanins were significantly reduced in stem inclusion treatments at the end of alcoholic fermentation, but after the 2 years bottle ageing, only DS100 treatment showed significantly lower anthocyanins than DS treatment. Stem inclusion treatments significantly increased tannin concentration. Total anthocyanins and tannins in wines reduced by 69%–71% and 24%–31% respectively after bottle ageing.
Grape stems impact on Pinot noir wine colour.
•Wine chemistry is defined in part by terroir (viticultural soil, aspect, & climate)•Analytical techniques have been used to characterise wines and to detect wine fraud.•We used ICP-MS & NMR to ...characterise bottled Pinot Noir wines from Australia and NZ.•Wines from Australian and NZ regions were somewhat distinguished using ICP-MS.•Neither NMR nor ICP-MS successfully distinguished between vintages.
Wine quality and character are defined in part by the terroir in which the grapes are grown. Metabolomic techniques, such as nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma mass spectrometry (ICP-MS), are used to characterise wines and to detect wine fraud in other countries but have not been extensively trialled in Australia. This paper describes the use of ICP-MS and NMR to characterise a selection of Pinot noir wines. Wines from varying terroirs could be somewhat distinguished by their mineral content using principal component analysis (PCA). PCA was able to separate wines by their Australian states more clearly than by region. Metabolomic analysis of the wines using NMR did not find any correlations with climate/daytime temperatures, or region. An analysis of coinertia suggested that the two datasets were not redundant, and it is proposed that ICP-MS data is the most useful for determining regionality.
Wine research has as its core components the disciplines of sensory analysis, viticulture, and oenology. Wine quality is an important concept for each of these disciplines, as well as for both wine ...producers and consumers. Any technique that could help producers to understand the nature of wine quality and how consumers perceive it, will help them to design even more effective marketing strategies. However, predicting a wine’s quality presents wine science modelling with a real challenge. We used sample data from Pinot noir wines from different regions of New Zealand to develop a mathematical model that can predict wine quality, and applied dimensional analysis with the Buckingham Pi theorem to determine the mathematical relationship among different chemical and physiochemical compounds. This mathematical model used perceived wine quality indices investigated by wine experts and industry professionals. Afterwards, machine learning algorithms are applied to validate the relevant sensory and chemical concepts. Judgments of wine intrinsic attributes, including overall quality, were made by wine professionals to two sets of 18 Pinot noir wines from New Zealand. This study develops a conceptual and mathematical framework to predict wine quality, and then validated these using a large dataset with machine learning approaches. It is worth noting that the predicted wine quality indices are in good agreement with the wine experts’ perceived quality ratings.
The performance of Patagonian Lactobacillus plantarum and Oenococcus oeni strains as malolactic starter cultures was compared. Two autochthonous strains of each species were selected, based on the ...presence of aroma-related genes, and inoculated in sterile wine of high ethanol content. The effects of initial inoculum size and acclimation treatment on the efficiency of malolactic fermentation (MLF) were analyzed for each strain. O. oeni strains were able to successfully conduct the MLF only when the inoculum concentration was higher than 1.108 CFU/mL and cells were acclimated in sublethal ethanol concentrations. The increase of ethanol concentration in the acclimation medium also improved the kinetics of malic acid consumption. Successful MLF with L. plantarum strains required lower inocula and no acclimation treatment. In addition, these strains showed a better profile of aroma-related genes than O. oeni. L. plantarum strains appeared to be more efficient than O. oeni strains as candidates for malolactic starter cultures to be used in Patagonian red wines.
•L. plantarum and O. oeni strains were isolated and fermentation examined.•L. plantarum was more efficient at MLF than O. oeni in Patagonian wines.•Standardization of acclimation and inoculum was necessary for successful MLF by O. oeni.•Acclimation in high ethanol content improved the malic acid consumption of O. oeni.•MLF with L. plantarum strains required lower inocula and no pre-acclimation treatment.
Fruit quality is dependent on various factors including flavour, texture and colour. These factors are determined by the ripening process, either climacteric or non-climacteric. In grape berry, which ...is non-climacteric, the process is signalled by a complex set of hormone changes. Abscisic acid (ABA) is one of the key hormones involved in ripening, while sugar availability also plays a significant role in certain ripening aspects such as anthocyanin production. To understand the relative influence of hormone and sugar signalling
can prove problematic due to the physiological and environmental (abiotic and biotic) factors at play in vineyards. Here we report on the use of
detached berry culture to investigate the comparative significance of ABA and sugar in the regulation of Pinot noir berry anthocyanin production under controlled conditions. Using a factorial experimental design, pre-véraison berries were cultured on media with various concentrations of sucrose and ABA. After 15 days of
culture, the berries were analysed for changes in metabolites, hormones and gene expression. Results illustrated a stimulatory effect of sucrose and ABA on enhancing berry colour and a corresponding increase in anthocyanins. Increased ABA concentration was able to boost anthocyanin production in berries when sucrose supply was low. The sucrose and ABA effects on berry anthocyanins were primarily manifested through the up-regulation of transcription factors and other genes in the phenylpropanoid pathway, while in other parts of the pathway a down-regulation of key proanthocyanindin transcription factors and genes corresponded to sharp reduction in berry proanthocyanidins, irrespective of sucrose supply. Similarly, increased ABA was correlated with a significant reduction in berry malic acid and associated regulatory genes. These findings suggest a predominance of berry ABA over berry sugar in coordinating the physiological and genetic regulation of anthocyanins and proanthocyanins in Pinot noir grape berries.
The compositional authentication of wine is of great interest, as the geographic origin of the grapes is often associated with quality, uniqueness, and authenticity. Previous elemental fingerprinting ...studies mainly discriminated wines from different countries or regions within a country. Here, we report the use of element profiles to distinguish commercial Pinot noir wines from five sub-regional appellations or neighborhoods within one American viticultural area (AVA). Fifty-three single cultivar wines were collected over two harvests and analyzed using microwave plasma-atomic emission spectroscopy (MP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS). Of 62 monitored elements that were quantified with fully validated methods, 24 and 32 elements differed significantly across the neighborhoods and vintages, respectively (
< 0.05). Targeted canonical variate analysis (CVA) explained 85%-90% of the variance ratio across the two vintages, indicating persistent and stable elemental fingerprints of wines at a sub-regional level. A sixth, newly founded neighborhood was correctly grouped separately from the others using a Soft Independent Modeling of Class Analogy (SIMCA), indicating the potential of elemental fingerprints for wine authenticity.
Carbon footprint studies of locally produced and consumed wine are missing.
The objective of the present study was to identify management strategies and carbon reduction potentials for a sustainable ...wine production based on the carbon footprint and the water footprint of locally grown grapes and wine locally produced and consumed.
Two wineries (A and B) were investigated, both of which grow the same white (Riesling) and the same red grape (Pinot Noir/Spätburgunder) on the same rootstock in the Rhine river valley of Germany. The study was based on PAS 2050-1 (BSI) and comprised 99% primary data derived from historical farm records. System boundaries ranged from planting of the grapevines to eventual disposal of a typical 0.75 L glass bottle, which served as the functional unit (FU).
The product carbon footprint (PCF) was 1.91 ± 0.3 kg CO2eq/bottle (A) or 1.69 ± 0.3 (B) kg CO2eq/bottle of white wine and 1.86 ± 0.3 kg CO2eq/bottle of red wine for both wineries. These results were attributed to the consumer behaviour (22–30%), followed by the use and production of glass bottles (20–27%). Grapevine cultivation amounted to 0.3–0.4 kg CO2eq/bottle; grape processing caused ca. 0.05–0.06 kg CO2eq/bottle, packaging 0.5–0.6 kg CO2eq/bottle, distribution 0.2–0.4 kg CO2eq/bottle, while use and disposal of the glass bottles emitted 0.5–0.6 kg CO2eq/bottle. The plant protection chemicals caused only ca. 1.4% and organic fertilizer ca. 2.8% of the product carbon footprint (PCF). Red and white wine appeared commensurate in their PCF within 3–8% in both vineyards. The water footprint was ca. 5.7 ± 0.6 (A) and 2.1 ± 0.4 (B) L blue water/bottle for both red and white wine.
The results are discussed with higher carbon footprint values for wine from overseas. We have identified the following reduction potentials such as the following management strategies:
a) reduction of fossil fuels for gas heating of the premises and for farm vehicles, b) the use of lightweight glass bottles and c) alternative means of transport for the consumer purchase at the winery when using a private vehicle.
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•Product carbon footprint ranged from 1.84 to 1.95 kg CO2eq/red or white wine bottle.•Plant protection amounted to 1.5 % (of PCF) and (organic) fertiliser to 3%.•Individual management strategies are suggested for both vineyards and wines – in winery B could save 10% of PCF.•Overall, management strategies include consumer shopping and light-weight glass bottles.
Ultraviolet and visible (UV–Visible) spectroscopy in conjunction with chemometrics modelling, was successfully applied to objectively differentiate grape juice press fractions (Vitis vinifera, ...cultivar Pinot Noir) for sparkling wine production. Two measurements modes were applied: (i) reflectance using a fiber optic probe in-line and (ii) transmission using a benchtop spectrophotometer. Different wavelength ranges for UV–Visible spectroscopy were evaluated and their ability to measure total phenolic concentrations in grape juice press fractions was compared. The differentiation of free run, early and late press fractions shows promise as a tool for the rapid discrimination of juice fractions when grapes for sparkling wine are pressed. Calibrations for total phenolics were prepared from press fraction spectral data using partial least squares (PLS) regression with a large number of wavelengths (230–700 nm) and multiple linear regression (MLR) using a small number of key wavelengths (230, 240, 280, 290, 520 nm). Calibration performance for both reflectance and transmission spectra was similar, but the best performing calibration used reflectance spectra at 240 and 290 nm (R2val = 0.95; SECV = 0.023 g/L; CV = 4.2%). Reflectance spectroscopy can thus be used in-line to predict total phenolics in grape juice with an acceptable accuracy and to discriminate press fractions. Insights arising from this research suggest a future possibility of objective, real-time discrimination of grape juice for better process control, monitoring and optimization of winemaking practices.
•Total phenolic concentrations were measured in grape juice press fractions.•A novel optical in-line system was built for phenolic content monitoring.•The best performing calibration resulted when using reflectance spectra at 240 and 290 nm.•Reflectance spectroscopy can be used in-line to predict total phenolics in press fractions.
This study was conducted in order to improve our understanding of how phenolics and aroma compounds change in wine grapes during postharvest dehydration. Pinot noir grapes grown in the Willamette ...Valley of Oregon were harvested at 22.0 and 24.0°Brix. Grapes harvested at 22.0°Brix were divided into three equal lots with one lot immediately used for wine production, and the remaining two lots placed inside an air tunnel with an air speed of 1.0–1.8ms−1, 38% relative humidity and a temperature of 22°C. The soluble solids content and weight loss were measured daily and wines were made from grapes when they reached 24.8 and 26.7°Brix. The soluble solids of grapes increased about 1°Brix per day; therefore, on the third and fourth day the berries reached the desired concentration; weight loss was 14 and 16%, respectively. Results from berry phenolic analysis indicated that per berry anthocyanin amount remained unchanged during dehydration. The composition of proanthocyanidins isolated from berries changed during dehydration. Volatile compounds in wines made from dehydrated grapes contained more terpenes and norisoprenoids (β-ionone, β-damascenone) when compared to wine made from the original fruit. Wines made from increasingly dehydrated grapes tended to resemble the composition and flavour profile of wines made from grapes left on the vine (i.e. with extended ripening). The results of this study suggest that postharvest flavour changes consistent with changes during fruit ripening can occur in grapes when harvested early and allowed to dehydrate under controlled conditions prior to fermentation.
Effect of grape maturity on aroma-active compounds in Pinot noir wine was investigated using stir bar sorptive extraction−gas chromatograph−mass spectrometry (SBSE-GC-MS). High correlation ...coefficient (>0.95) and low standard deviation (<10%) were obtained for all aroma-active compounds of interest. Two vintages of Pinot noir wines with three different grape maturities each were analyzed. Statistical analysis showed that both grape maturity and growing year significantly affected the aroma composition of the final wine. Analysis of wine samples from the same vintage indicated that grape maturity could affect aroma compounds in different ways, based on their biochemical formation in the wines. For most short-chain fatty acid esters, there were no obvious trends with grape maturity, however, the concentrations of ethyl 2-methylpropanoate and ethyl 3-methylbutanoate consistently decreased with grape maturity. The decreasing trend was also observed for other esters including ethyl cinnamate, ethyl dihydroxycinnamate, and ethyl anthranilate, with the exception of ethyl vanillate, while C13 norisoprenoids, monoterpenes, and guaiacols had increasing trends with grape maturation. Keywords: Stir bar sorption extraction (SBSE); aroma; Pinot noir wine; grape maturity
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