Discrimination of aging wines with alternative oak products and micro-oxygenation by FTIR-ATR

The use of alternative oak wood products (AOP), such as chips, cubes and staves, among other, from different geographical origins is a common practice for wine aging, where the micro-oxygenation (MOX, adding small doses of oxygen constantly over time) is essential to obtain a final wine more stable in time and with similar characteristics of barrel-aged wine. The aim of this work was to identify if spectroscopic techniques allow to discriminate wines aged with alternative oak products (chips and staves) from different oak woods (American, French and Spanish) and a floating micro-oxygenation (20 µg·L−1) after 10 years of bottling and compared to those aged in barrels. The spectral information and analysis were performed in a FTIR-ATR, with 128 scans per spectrum at a spectral resolution of 8 cm-1 in the wavenumber range from 4,000 to 450 cm-1. Principal component analyses of spectral information were performed using the Unscrambler® X. The results indicate that with this technique it is possible to clearly separate the wines aged by the three systems (chips, staves and barrels) in the case of American oak. In the case of French oak, wines aged in chips were clearly differentiated from wines aged in staves with those aged in barrels between the two. It is also possible to clearly separate aged wines with different Spanish oak systems. The application of FTIR-ATR appears to be a powerful technique for discriminating the quality of wines aged by different AOPs and wood barrels from different geographical origins

Wine Aging Technologies

Wine aging is a desirable and valuable process, commonly used to improve wine quality, and traditionally carried out in oak wooden casks [...

Wine Aging Technologies

Wine aging is a desirable and valuable process, commonly used to improve wine quality, and traditionally carried out in oak wooden casks. The correct use of oak barrels and the ever-increasing demand for barrels in the different production areas of the world has led to a constant search for technological alternatives to reproduce the chemical and physical processes undergone by wines during their stay in barrels.The aim of this Special Issue is to publish a compilation of original research and revision works that cover different aspects of the ageing processes of wine in casks and other alternative systems that reproduce, with different technologies, the transformations that take place in the barrel.Important aspects to be addressed are:the type of technological solutions that exist for wine agingthe impact of these new technologies on the final productcomparison of the effect of emerging and traditional technologies on the wine ageddifferentiation of wines undergoing different systems to avoid fraudcharacterization of the new materials used in barrel productionaccelerated aging of wines with wood and oxyge

Characterization of the Oxygen Transmission Rate of New-Ancient Natural Materials for Wine Maturation Containers

Today, there is a trend in enology promoting a return to the use of old natural materials for the manufacture of storage and maturation wine tanks. One of the most sought-after characteristics of these materials is their permeability to oxygen from the atmosphere to improve wines without this being a harmful process. The reference performance in wine aging is, without doubt, the oak barrel for its ability to oxidize wines in a controlled way, thus improving them. It would be possible to mature wines in containers in which the use of wood is not obligatory, as opposed to aging in oak barrels or foudres. This work presents the results of oxygen permeation analysis under test conditions typical of a tank containing wine, using materials, such as concrete and granite. The oxygen permeability of the materials tested was very diverse, typical of natural materials. The results showed that earthenware presents an excessive permeability, not only to atmospheric oxygen, but also to liquids and needs treatment before being used in liquid containers. Claystone and concrete can be impermeable to liquids, but maintain permeability to atmospheric oxygen—making them candidates for use in permeable tanks for wine maturation. Finally, granite has some very interesting characteristics, though thickness control is required when calculating the desired oxygen transmission rate

Artificial Intelligence Methods for Constructing Wine Barrels with a Controlled Oxygen Transmission Rate

Oxygen is an important factor in the wine aging process, and the oxygen transmission rate (OTR) is the parameter of the wood that reflects its oxygen permeation. OTR has not been considered in the cooperage industry yet; however, recent studies proposed a nondestructive method for estimating the OTR of barrel staves, but an efficient method to combine these staves to build barrels with a desired OTR is needed to implement it in the industry. This article proposes artificial intelligence methods for selecting staves for the construction of barrel heads or bodies with a desired target OTR. Genetic algorithms were used to implement these methods in consideration of the known OTR of the staves and the geometry of the wine barrels. The proposed methods were evaluated in several scenarios: homogenizing the OTR of the actual constructed barrels, constructing low-OTR and high-OTR barrels based on a preclassification of the staves and implementing the proposed method in real cooperage conditions. The results of these experiments suggest the suitability of the proposed methods for their implementation in a cooperage in order to build controlled OTR barrels

Alternative Woods in Oenology: Volatile Compounds Characterisation of Woods with Respect to Traditional Oak and Effect on Aroma in Wine, a Review

The interest of winemakers to find new woods that can give their wines a special personality and the need for cooperage wood have led to the use of other woods than traditional oak. The aroma of wines is undoubtedly one of the quality factors most valued by consumers. Volatile compounds from wood are transferred to wines during ageing. The type and quantity of aromas in wood depend on several factors, with the species, origin and cooperage treatments, particularly toasting, being very important. The transfer of volatile compounds to the wine depends not only on the wood but also on the wine itself and the type of ageing. This review therefore aims to recapitulate the volatile composition of alternative oenological woods at different cooperage stages and to compare them with traditional woods. It also summarises studies on the effect of wine aromas during ageing both in barrels and with fragments of alternative woods. In summary, it is observed that both woods and wines aged with alternative species of the Quercus genus present the same volatile compounds as traditional ones, but differ quantitatively; however, non-Quercus woods also differ qualitatively

Evaluation of grape pomace from red wine by-product as feed for sheep

9 páginas, 4 tablas, 3 figuras.This work aimed to study the chemical composition and in vitro digestibility of seeds and pulp from grape pomace. In sacco degradability, ruminal fermentation of grape pomace fractions and plasma lipid peroxidation were also studied in sheep fed with or without grape pomace. RESULTS: Seed and pulp fractions of grape pomace had different values for cell walls (523 vs 243 g kg dry matter (DM)), crude protein (CP, 104 vs 138 g kg DM), ether extract (EE, 99.0 vs 31.7 g kg DM), polyunsaturated fatty acids (PUFA, 69.6 vs 53.3%) and extractable polyphenols (55.0 vs 32.1 g kg DM). The in vitro true digestibility, DM in sacco degradability and CP degradability of seeds and pulp were also different (0.51 vs 0.82, 0.30 vs 0.45 and 0.66 vs 0.39 respectively). The ammonia-N concentration and total volatile fatty acids (VFA) in ruminal liquid were significantly lower and plasma lipid peroxidation was also numerically lower in sheep that consumed grape pomace. CONCLUSION: The nutritive value of grape pomace varies depending on the proportion of seeds and pulp. The interest of this by-product in sheep feeding could be related to its polyphenol and PUFA content, which could improve meat and milk quality. © 2016 Society of Chemical Industry.This work was subsidized by INIA (RTA2010-0068-C02) andthe Consejería de Educación de la Junta de Castilla y León(VA196A11-2). Cristina Guerra-Rivas was supported by an FPUgrant (FPU AP-2010-0571) from the Spanish Ministry of Education.We would also like to thank Escuela de Capacitación Agraria deViñalta (Junta de Castilla y León) for the facilities and the animalsused in this study.Peer Reviewe

In-situ monitoring of wine volume, barrel mass, ullage pressure and dissolved oxygen for a better understanding of wine-barrel-cellar interactions

International audienceThe process of aging wine in oak barrels causes various mechanisms that modify wine quality. This study is devoted to understanding the gas and wine transfers that occur through the barrels depending on ambient conditions. Four barrels were instrumented in a cellar to monitor the liquid's height and evaporation rates, the ullage space pressure, the content of dissolved oxygen in the wine and the environmental conditions. The liquid wine progressed slowly through the wood and reached a stabilized position after approximately 100 days. Evaporation was initially very limited and then achieved an average rate of 20 mL per day after linearization of the moisture content profile. The evaporation rate was directly impacted by the cellar conditions. The negative pressure inside the barrels, created following the loss of wine, was also affected by the cellar conditions. Above a certain negative pressure, an air percolation threshold was reached, implying the rapid entry of air into the barrel