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Background: Three clones of Cabernet Franc (Nos. 02, 010 and 012) were selected in the last phase of clonal selection in Serbia. Wines made from each clone were assessed for quality parameters and taste during five consecutive vintages (2008-2012) and compared to the standard. The wine quality was determined based on the following parameters: alcohol, total extract, anthocyanins, tannins, pH, titratable acidity, volatile acidity, aldehydes, esters and reducing sugars, relative density, ash, colour, tonality, and tasting score. In the last year of the study, grapes and wines of Cabernet Franc clones and a standard were subjected to a chemical analysis of their phenolic composition, resveratrol and radical scavenging activity. In the last year of the study, grapes and wines of Cabernet Franc clones and a standard were subjected to a chemical analysis of their phenolic composition, resveratrol and radical scavenging activity., Methods: Chemical analyses of grapes and wines along with sensory and radical scavenging activity evaluations were done according to the standard procedures., Results: The wines of the clone No. 010 showed some superior properties compared to the other two clones and the standard; in five-year period the average concentration of anthocyanins (179±3.8 mg/L) and polyphenolics (1.85±0.02 g/L) was significantly higher than in wines of clones and the standard, (168-173 mg/L and 1.63-1.74 g/L for anthocyanins and phenolics, respectively). Furthermore, the same clone had a higher alcohol content (13.97±0.03%) in each year of the study, which indicated that it ripened faster than other clones (13.06-13.08 %) and compared to the standard (13.04±0.07%). This finding suggested that the clone No. 010 could possibly have a significant economic impact and further increase popularity of Cabernet Franc in a cooler climate viticultural region. It was also found to have the highest contents of aldehydes (488±1.54 mg/L) and esters (322±0.71 mg/L) compared to aldehydes (452-467 mg/L) and esters (290-310 mg/L) measured in other wines. Finally, the highest amount of phenolic compounds (1220±40 mg/kg) and resveratrol (70±3.3 mg/kg) were found in the grapes of the clone No. 010. The present study revealed a strong correlation of total phenolic contents and anthocyanins with radical scavenging activities (0.936 and 0.929, P<0.001, respectively) indicating that this activity of wines was derived mainly from their phenolic compounds., Conclusion: The wine of the clone No. 010 contained the highest concentration of aldehydes, esters, anthocyanins, polyphenolics and resveratrol and consequently achieved the best tasting score. This clone may offer a new Cabernet Franc wine with geographical indication., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

This study investigated the effect of different contexts on consumers' mood, product-evoked emotions, liking and willingness to pay for wine. Three consumer trials (n=114, 115, and 120) examined 3 different sample sets of 4 Australian commercial Shiraz wines. Each sample set was comprised of a high, medium-high, medium-low and low quality wine as designated by an expert panel. Wine consumers evaluated the same set of wines in the three different contexts, ranging from a highly-controlled laboratory setting to more realistic restaurant and at-home settings. Results showed that high quality wines were liked more and elicited more intense emotions of positive valence compared to wines of lower quality. Context effects were observed on emotions, but not on liking, indicating that although emotions and liking are correlated, the measurement of emotions can deliver additional information over liking. Tasting wine in the restaurant context evoked more intense positive emotions compared to the home and laboratory contexts. Participants' mood before tasting the wines had a strong influence on consecutive product-evoked emotion ratings, but only weak influence on liking ratings. Furthermore, a strong relationship between wine-evoked emotions and willingness to pay was observed, showing that if a wine-evoked more intense emotion of positive valence e.g., contented, enthusiastic, happy, optimistic and passionate participants were willing to pay significantly more for a bottle. Additionally, the absence of negative emotions, even if typically evoked to a very weak extent, is a requirement for an increased willingness to pay. This study indicates it is worthwhile to consider context and emotions in wine testing and marketing., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Bushfire smoke can affect the composition and sensory properties of grapes and wines, in some cases leading to wines which exhibit undesirable "smoky", "ashy" and "medicinal" characters. This study investigated the extent to which fruit maturity (i.e., ripeness) influences the perception of smoke taint in wine. Two white grape varieties (Chardonnay and Sauvignon Blanc) and two red grape varieties (Merlot and Shiraz) were exposed to smoke under experimental conditions, at approximately seven days post-veraison. Fruit was then harvested at two levels of maturity: Harvest A, when total soluble solids were 16-20 °Brix, i.e., the berry ripeness typically required for production of sparkling or light-bodied wines; and Harvest B, when total soluble solids were 22-25 °Brix, i.e., the berry ripeness typically required for production of full-bodied wines. The intensity of smoke taint in resulting wines was found to be influenced by fruit maturity, but differed between grape varieties. Smoke-related sensory attributes were apparent in Sauvignon Blanc wine made from early-harvested fruit and in Chardonnay wine made from late-harvested fruit, only; whereas Merlot and Shiraz wines exhibited smoke taint irrespective of fruit maturity. Smoke-derived volatile phenols, and various alcohols, esters and acids, were also quantified to determine the impact of smoke exposure and fruit maturity respectively, on wine composition.

In this study, the suitability of attenuated total reflection (ATR) mid-infrared (MIR) spectroscopy, combined with principal component analysis (PCA) and partial least squares (PLS) regression, was evaluated as a rapid analytical technique for the classification of sparkling wine style and quality. Australian sparkling wines (n = 139) comprising a range of styles (i.e., white, rosé, red, Prosecco and Moscato) were analyzed by ATR-MIR spectroscopy combined with multivariate data analysis. The MIR spectra of 50 sparkling white wines, produced according to four different production methods (i.e., Carbonation, Charmat, Transfer and Methodé Traditionelle) were also evaluated against: (i) quality ratings determined by an expert panel; and (ii) sensory attributes rated by a trained sensory panel. Wine pH, titratable acidity (TA), residual sugar (RS), alcohol and total phenolic content were also determined. The sparkling wine styles were separated on the PCA score plot based on their MIR spectral data; while the sparkling white wines showed separation based on production method, which strongly influenced the style and sensory properties of wine (i.e., the intensity of fruit versus yeast-derived characters). PLS calibrations of 0.73, 0.77, 0.82 and 0.86 were obtained for sweetness, tropical fruit, confectionary and toasty characters (on the palate), respectively.

Volatile sulfur compounds contribute characteristic aromas to foods and beverages and are widely studied, because of their impact on sensory properties. Certain thiols are particularly important to the aromas of roasted coffee, cooked meat, passion fruit, grapefruit, and guava. These same thiols enhance the aroma profiles of different wine styles, imparting pleasant aromas reminiscent of citrus and tropical fruits (due to 3-mercaptohexan-1-ol, 3-mercaptohexyl acetate, 4-mercapto-4-methylpentan-2-one), roasted coffee (2-furfurylthiol), and struck flint (benzyl mercaptan), at nanogram-per-liter levels. In contrast to the usual gas chromatography (GC) approaches, a simple and unique high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for routine analysis of five wine thiols, using 4,4'-dithiodipyridine (DTDP) as a derivatizing agent and polydeuterated internal standards for maximum accuracy and precision. DTDP reacted rapidly with thiols at wine pH and provided stable derivatives, which were enriched by solid-phase extraction (SPE) prior to analysis by HPLC-MS/MS. All steps were optimized and the method was validated in different wine matrices, with method performance being comparable to a well-optimized but more cumbersome gas chromatography-mass spectrometry (GC-MS) method. A range of commercial wines was analyzed with the new method, revealing the distribution of the five thiols in white, red, rosé, and sparkling wine styles.

In this study, two-dimensional correlation spectroscopy (2D-COS) combined with mid-infrared (MIR) spectroscopy was evaluated as a novel technique for the identification of spectral regions associated with smoke-affected wine, for the purpose of screening taint arising from grapevine exposure to smoke. Smoke-affected wines obtained from experimental and industry sources were analysed using MIR spectroscopy and chemometrics, and calibration models developed. 2D-COS analysis was used to generate synchronous data maps for red and white cask wines spiked with guaiacol, a marker of smoke taint. Correlations were observed at wavelengths that could be attributable to aromatic C-C stretching, i.e., between 1400 and 1500 cm(-1), indicative of volatile phenols. These results demonstrate the potential of 2D-COS as a rapid, high-throughput technique for the preliminary screening of smoke tainted wine., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

In this study, the suitability of mid-infrared (MIR) spectroscopy, combined with principal component analysis (PCA) and linear discriminant analysis (LDA), was evaluated as a rapid analytical technique to identify smoke tainted wines. Control (i.e., unsmoked) and smoke-affected wines (260 in total) from experimental and commercial sources were analyzed by MIR spectroscopy and chemometrics. The concentrations of guaiacol and 4-methylguaiacol were also determined using gas chromatography-mass spectrometry (GC-MS), as markers of smoke taint. LDA models correctly classified 61% of control wines and 70% of smoke-affected wines. Classification rates were found to be influenced by the extent of smoke taint (based on GC-MS and informal sensory assessment), as well as qualitative differences in wine composition due to grape variety and oak maturation. Overall, the potential application of MIR spectroscopy combined with chemometrics as a rapid analytical technique for screening smoke-affected wines was demonstrated.

The dissolution kinetics of alpha-lactose monohydrate (alphaLM) single crystals were studied by a flow-cell method at different undersaturations. Linear dissolution profiles were obtained as a function of time for all the faces except the (010) face. The dissolution rates, obtained from these profiles, were anisotropic and varied considerably with undersaturation. At low undersaturations (0-2%), the order of dissolution rate was (110) > (100) > (011) = (110) > (010). This order changed with increasing undersaturation (>5%) to (011) >> (100) > (110) > (110) > (010). In alphaLM crystals in which lattice strain was induced by synchrotron X-irradiation, the rates of dissolution of all faces increased with increasing strain. The increase was less significant for the (011) faces than for the remainder. Under this constraint, the (010) face became the fastest dissolving one and the [011]face became the slowest one. The results of all experiments are explained on the basis that although dislocations may act as initiating dissolution centers at very low undersaturations, these sources rapidly give way to two-dimensional nucleation of randomly distributed dissolution sites as the undersaturation is increased. Under these conditions, which better reflect the normal dissolution processes of materials, bulk lattice strain plays the most significant role in defining the dissolution rate. The results show a potential route to the controlled engineering of the dissolution behavior of crystalline materials., (Copyright 2002 Wiley-Liss Inc. and the American Pharmaceutical Association)

The bulk crystallization of alpha-lactose monohydrate from aqueous solution by primary nucleation has been studied under controlled conditions of supersaturation, temperature, and pH. The induction times to nucleation were extremely long compared with those generally observed for other materials, even at the high supersaturations used in the experiment. As a result, it was necessary to stir the supersaturated solution vigorously to induce nucleation in a reasonable but still lengthy working time. Even then, nucleation only occurred to a limited extent, following which growth ceased for 8-10 h before resuming. After this period, growth recommenced but again slowed to a low rate after another 8 h. At this stage, the yield of product was low and in most cases the particles had achieved sizes close to the maximum noted. The yields increased with further crystallization time (22-72 h total from the recommencement of growth) to give, under high initial supersaturation conditions, amounts of product close to the theoretical value. For the most part, however, the particle size did not increase with this later increase in yield, showing only significant changes after the extremely long total crystallization times. It is proposed that these extreme properties result from the formation in solution by mutarotation of the anomer alpha-lactose, which inhibits nucleation as well as its previously observed influence on growth.