A review on the aroma composition of Vitis vinifera L. Pinot noir wines: origins and influencing factors.

Vitis vinifera L. Pinot noir still wines are some of the most popular and expensive red wines in the world. Several research articles are reported in literature concerning the impacts of viticultural and enological practices, and vineyard location, on Pinot noir still wine aroma. This review summarizes the previous and latest literature pertaining to volatile compounds including esters, higher alcohols and C13-norisoprenoids, and their effect on Pinot noir wine perceived aroma. Their origin and behavior are discussed, as well as their role in regional differentiation. The first part of this review paper presents an overview of volatile compounds that are usually found in Pinot noir still wines at concentrations higher than their odor detection threshold. The second part deals with studies pertaining to human inputs that impact on Pinot noir wine aroma profile such as viticulture and winemaking interventions. The role of the vineyard site is also revised. This review concludes by considering what further opportunities are available to researchers in this field for greater control over Pinot noir wine quality outcomes.

Preliminary Study of Australian Pinot Noir Wines by Colour and Volatile Analyses, and the Pivot© Profile Method Using Wine Professionals.

The aim of this preliminary study was to identify potential colour components, volatile and sensory attributes that could discriminate Pinot noir wines from five Australian winegrowing regions (Adelaide Hills, Yarra Valley, Mornington Peninsula, Northern and Southern Tasmania). The sensory analysis consisted of the Pivot© Profile method that was performed by wine professionals. A headspace solid-phase microextraction-gas chromatography-mass spectrometry method was used to quantify multiple volatile compounds, while the Modified Somers method was used for colour characterisation. Analysis of data suggested ethyl decanoate, ethyl 2-methylpropanoate, ethyl 2-methylbutanoate, in addition to decanoic acid as important contributors to the discrimination between regions. Similarly, wine hue, chemical age indices, total anthocyanin, and (%) non-bleachable pigment also discriminated wines between regions. The sensory analysis showed that wines from Mornington Peninsula were associated with the 'red fruits' aroma, 'acidic', and 'astringency' palate descriptors, while those from Adelaide Hills were associated with the 'brown' colour attribute. This study indicates regionality is a strong driver of aroma typicity of wine.

SPME Method Optimized by Box-Behnken Design for Impact Odorants in Reduced Alcohol Wines.

The important sampling parameters of a headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure such as the extraction temperature, extraction time, and sample volume were optimized to quantify 23 important impact odorants in reduced alcohol red and white wines. A three-factor design of Box-Behnken experiments was used to determine the optimized sampling conditions for each analyte, and a global optimized condition at every ethanol concentration of interest determined using a desirability function that accounts for a low signal response for compounds. Shiraz and Chardonnay wines were dealcoholized from 13.7 and 12.2% v/v ethanol respectively, to 8 and 5% v/v, using a commercially available membrane-based technology. A sample set of the reduced alcohol wines were also reconstituted to their natural ethanol level to evaluate the effect of the ethanol content reduction on volatile composition. The three-factor Box-Behnken experiment ensured an accurate determination of the headspace concentration of each compound at each ethanol concentration, allowing comparisons between wines at varying ethanol levels to be made. Overall, the results showed that the main effect of extraction temperature was considered the most critical factor when studying the equilibrium of reduced alcohol wine impact odorants. The impact of ethanol reduction upon the concentration of volatile compounds clearly resulted in losses of impact odorants from the wines. The concentration of most analytes decreased with dealcoholization compared to that of the natural samples. Significant differences were also found between the reconstituted volatile composition and 5% v/v reduced alcohol wines, revealing that the dealcoholization effect is the result of a combination between the type of dealcoholization treatment and reduction in wine ethanol content.

Volatile and sensory profiling of Shiraz wine in response to alcohol management: comparison of harvest timing versus technological approaches.

The aim of this study was to compare the volatile and sensory profiles of Australian Shiraz red wines produced by several methods to achieve alcohol concentrations of 10.5 and 13.5% v/v. These levels were considerably lower contents than the commercial wine (16-17% v/v) that was produced from this vineyard site. Wines were produced by: (i) harvest timing (19.3, 24 and 29.3 Brix); (ii) blending equal proportions of early harvest (19.3 Brix) and late harvest wines (29.3 Brix); and (iii) dealcoholization using reverse osmosis followed by a membrane contactor. Dealcoholization caused a significant loss of volatile compounds, particularly esters, while the blending treatment had an averaging effect on most analytes. Sensory descriptive analysis of treatments with 10.5% v/v alcohol showed that the perception of the herbaceous attribute was more intense in the early harvest wines in comparison to the dealcoholized wines, while those of dark fruit, raisin/prune, astringency and alcohol were lower. No sensory differences were found amongst the 13.5% v/v wines, except for alcohol. Sensory and compositional data were modelled by means of Common Dimension (ComDim) multi-block analysis and indicated which chemical components are important to the perceived wine sensory properties. Insights from this study will provide knowledge that may be applied to control or moderate both unripe sensory attributes in addition to a deficiency of ripe fruit aromas or mouthfeel characteristics in reduced-alcohol red wines.

A comparative study of partial dealcoholisation versus early harvest: Effects on wine volatile and sensory profiles.

Two Verdelho and Petit Verdot wines were produced from sequential harvests of grapes. The alcohol concentration of early harvest (EH) and late harvest (LH) wines were respectively 9% and 13.5% v/v for Verdelho, and 10.5% and 13% v/v for Petit Verdot. LH wines were dealcoholised to match the same alcohol level of EH samples using a combined reverse osmosis-evaporative perstraction process. In dealcoholised wines, there was a decrease in volatile compounds (esters particularly) compared to LH treatments. For both varieties, the sensory attribute ratings for overall aroma intensity and alcohol mouthfeel also decreased following dealcoholisation. Dealcoholised wines were distinctively different from both LH and EH wines even though these wines had similar alcohol level to EH wines. When dealcoholisation is considered for high-alcohol wines, it is important to consider that membrane effects can significantly change depending on the wine non-volatile matrix composition and the level of alcohol reduction required.

Harvesting and blending options for lower alcohol wines: a sensory and chemical investigation.

BACKGROUND: Lower alcohol wines often have a poor reputation among consumers, in part due to their unsatisfactory flavours such as reduced overall aroma intensity or herbaceous characters. The aim of this study, performed on Verdelho and Petit Verdot, was to quantify the effectiveness of a monovarietal blend in which wines made from less ripe grapes were blended with an equivalent volume of a wine vinified from riper fruit to produce wines with a lower alcohol content and desirable ripe fruit flavours. RESULTS: Eleven and 13 attributes, for Verdelho and Petit Verdot, respectively, were selected during sensory descriptive analysis. Intensities of perceived 'acidity', 'sweetness' and 'alcohol' attributes were significantly different (P ≤ 0.05) between the blend (8.8 ± 0.1% v/v) and mature Verdelho (10.3 ± 0.1% v/v) wines, while no significant differences were found between the Petit Verdot blend (11.0 ± 0.1% v/v) and mature (12.6 ± 0.2% v/v) treatments. Volatile composition of wines was assessed using HS-SPME-GC-MS. Partial least square regression suggested relationships between sensory descriptors and chemical attributes in the wines, as well as the modifications of sensory and compositional profiles following blending. CONCLUSIONS: The blending practice described allowed the production of wines with lower alcohol content while retaining similar sensory profiles of the later harvested, riper fruit wines. © 2017 Society of Chemical Industry.

Changes in volatile composition and sensory attributes of wines during alcohol content reduction.

A desirable sensory profile is a major consumer driver for wine acceptability and should be considered during the production of reduced-alcohol wines. Although various viticultural practices and microbiological approaches show promising results, separation technologies such as membrane filtration, in particular reverse osmosis and evaporative perstraction, in addition to vacuum distillation, represent the most common commercial methods used to produce reduced-alcohol wine. However, ethanol removal from wine can result in a significant loss of volatile compounds such as esters (ethyl octanoate, ethyl acetate, isoamyl acetate) that contribute positively to the overall perceived aroma. These losses can potentially reduce the acceptability of the wine to consumers and decrease their willingness to purchase wines that have had their alcohol level reduced. The change in aroma as a result of the ethanol removal processes is influenced by a number of factors: the type of alcohol reduction process; the chemical-physical properties (volatility, hydrophobicity, steric hindrance) of the aroma compounds; the retention properties of the wine non-volatile matrix; and the ethanol level. This review identifies and summarises possible deleterious influences of the dealcoholisation process and describes best practice strategies to maintain the original wine composition. © 2016 Society of Chemical Industry.

Effect of Boswellia serrata on intestinal motility in rodents: inhibition of diarrhoea without constipation.

Clinical studies suggest that the Ayurvedic plant Boswellia serrata may be effective in reducing diarrhoea in patients with inflammatory bowel disease. In the present study, we evaluated the effect of a Boswellia serrata gum resin extract (BSE) on intestinal motility and diarrhoea in rodents. BSE depressed electrically-, acetylcholine-, and barium chloride-induced contractions in the isolated guinea-pig ileum, being more potent in inhibiting the contractions induced by acetylcholine and barium chloride. The inhibitory effect of BSE on acetylcholine-induced contractions was reduced by the L-type Ca(2+) channel blockers verapamil and nifedipine, but not by the sarcoplasmic reticulum Ca(2+)-ATPase inhibitor cyclopiazonic acid, by the phosphodiesterase type IV inhibitor rolipram or by the lipoxygenase inhibitor zileuton. 3-acetyl-11-keto-beta-boswellic acid, one of the main active ingredients of B. serrata, inhibited acetylcholine-induced contractions. BSE inhibited upper gastrointestinal transit in croton oil-treated mice as well as castor oil-induced diarrhoea. However, BSE did not affect intestinal motility in control mice, both in the small and in the large intestine. It is concluded that BSE directly inhibits intestinal motility with a mechanism involving L-type Ca(2+) channels. BSE prevents diarrhoea and normalizes intestinal motility in pathophysiological states without slowing the rate of transit in control animals. These results could explain, at least in part, the clinical efficacy of this Ayurvedic remedy in reducing diarrhoea in patients with inflammatory bowel disease.

New sesquiterpenes with intestinal relaxant effect from Celastrus paniculatus.

The seed oil obtained from Celastrus paniculatus has been used in Ayurvedic medicine for the treatment of several complaints including intestinal disorders. The muscle relaxing activity of C. paniculatus has been studied in vitro on isolated preparations of rat intestine. C. paniculatus seeds extract (0.001 - 100 microg/mL) produced a concentration-related relaxation of the rat ileum [IC (50) (95 % c. l.) 0.24 (0.13 - 0.45) microg/mL]. Among the four fractions ( n-hexane, CCl (4), CHCl (3), n-BuOH) obtained from the methanolic extract of C. paniculatus, only the carbon tetrachloride fraction (0.01 - 10 000 ng/mL) induced a significant relaxation of the intestinal muscle [IC (50) (95 % c. l.): 1.9 (1.38 - 2.87) ng/mL]. Three new sesquiterpene polyol esters have been isolated from the carbon tetrachloride fraction. These new metabolites, characterised as 1alpha,8beta,14-triacetoxy-9beta-furoyloxydihydro-beta-agarofuran ( 1), 1alpha, 6beta,8beta,14-tetraacetoxy-9beta-benzoyloxydihydro-beta-agarofuran ( 2) and 1alpha,8beta-diacetoxy-9beta-benzoyloxydihydro-beta-agarofuran ( 3), at the concentration of 1 microg/mL produced a relaxant effect of 30.6 +/- 12.2 %, 26.9 +/- 4.7 % and 7.27 +/- 1.7 %, respectively.

The role of the phenethyl ester of caffeic acid (CAPE) in the inhibition of rat lung cyclooxygenase activity by propolis.

In this study we investigated the effect of an ethanolic extract of propolis, with and without CAPE, and some of its components on cyclooxygenase (COX) activity. Propolis (0.00003-0.03%) significantly and concentration-dependently inhibited COX activity from lung homogenate of saline- or LPS-treated rats. Same results were obtained with CAPE (0.1-100 microM). COX activity from lung homogenate of saline- or LPS-treated rats was also inhibited by galangin (0.1-100 microM), although the inhibition induced by the lowest concentration was not significant. Caffeic, ferulic, cinnamic and chlorogenic acids and pinocembrin, (0.1-100 microM) did not affect COX activity. The inhibition curves showed that CAPE and propolis were equipotent inhibitors, whereas galangin was significantly (P<0.001) less potent than propolis and CAPE. In order to better investigate the role of CAPE, we tested the action of an ethanolic extract of propolis (0.00003-0.03%) without CAPE. This extract significantly and concentration-dependently inhibited COX activity from lung homogenate of saline- or LPS-treated rats, however, it resulted to be approximately 10 times less potent than the extract containing CAPE. The analysis of the inhibition curves of the extract with and without CAPE showed a significant (P<0.001) difference. These results suggest that both CAPE and galangin contribute to the overall activity of propolis, CAPE being more effective.