Influence of the Storage in Bottle on the Antioxidant Activities and Related Chemical Characteristics of Wine Spirits Aged with Chestnut Staves and Micro-Oxygenation

Different ageing technology of wine spirits (WSs) has been investigated, but little has been published on the chemical evolution of aged WS during storage in bottle. The purpose of this study was to examine how 12 months of storage in bottle affected the evolution of antioxidant activity (DPPH, FRAP and ABTS assays), total phenolic index (TPI) and low molecular weight (LMW) compounds content of the WSs aged through alternative technology using three micro-oxygenation levels (MOX) and nitrogen control (N). Results revealed the ability of phenolic compounds from aged WSs to scavenge free radicals during storage in bottle. Among the in vitro antioxidant-activity methods, FRAP assay was the more effective to differentiate WSs according to the ageing technology. Concerning the overall influence of storage in bottle on antioxidant activity, and TPI and LMW compounds content, the higher results were obtained for the MOX modalities (O15, O30 and O60), which showed a similar evolution. In summary, this study provides innovative information, demonstrating that the differences between the aged WSs imparted throughout the ageing process (resulting from different MOX levels) were mostly retained, and only slight modifications during storage in bottle were found.

The Effect of Elicitors and Canopy Management in the Chemical Composition of Vitis vinifera Red Varieties in Warm and Hot Areas in Spain

Canopy management practices in vineyards, such as sprawling systems and shoot trimming, can change the accumulation of metabolites in grapes. The use of elicitors of biological origin on grapevines of Vitis vinifera red grape varieties may also modulate the chemical composition of the berries. These modifications are often observed in the accumulation of phenolic compounds, including pigments. Both technical approaches are alternatives involved in minimizing the effects of global climate change in warm areas. The increase of temperature related to climate change accelerates the accumulation of sugars, but produces unbalanced grapes. This work establishes the use of button sensors to monitor the climate changes occurring at grape cluster level. Together with climate monitoring, conventional instrumental analytical techniques are used to follow up the chemical composition and the phenolic fraction of grapes in four different production areas in Spain. The effect of either treatment seems variable and to be affected by external factors besides the treatment itself and the climate conditions. While there is a fine effect that correlates with the use of elicitors in varieties like Merlot and Tempranillo, there is minimal improvement observed in Tintilla de Rota. The total phenolic index increases were between 2.3% and 11.8% in the first two parcels. The same happened with the vineyard’s canopy management systems, with increased pigment accumulation and the total phenolic index rising (37.7% to 68.7%) after applying intense shoot trimming, or a variation in sugar concentrations when using sprawl conduction. This study aims to provide viticulturists and oenologists in particular, and farmers in general, with data on the field regarding the use of alternative sustainable practices in the cultivation of grapes. The techniques used involved 100% natural products without adjuvants. The benefits obtained from applying some of these practices would be to produce technically mature grapes despite climate changes, and the elaboration of more balanced wines.

Antioxidant activity and phenolic composition of wine spirit resulting from an alternative ageing technology using micro-oxygenation: a preliminary study

Aim: Alternative technologies for the aging of wine spirit, as for other spirit beverages, have been developed over the past decade in order to meet consumer and industry expectations of differentiation and sustainability. Physicochemical characterisation of the resulting products has been carried out, but no previous research has evaluated their antioxidant activity. This preliminary study examined the effect of an alternative ageing technology (micro-oxygenation combined with wood staves from chestnut or Limousin oak in 1000 L stainless steel tanks) in comparison with traditional technology (250 L new barrels) on the antioxidant activity and related phenolic composition of the wine spirit.Methods and results: The wine spirits resulting from both technologies were sampled after 8, 15, 30, 180 and 365 days of ageing. Samples taken were analysed using the DPPH method, HPLC and total phenolic index. Significantly higher antioxidant activity (50.43 % vs 36.42 % DPPH inhibition), together with greater enrichment in wood-derived compounds (51.79 vs 27.72 total phenolic index), was achieved in wine spirits aged using the alternative technology than in new barrels. Moreover, chestnut wood stood out from Limousin oak wood with higher promoted antioxidant activity (62.69 % vs 21.35 % DPPH inhibition), and higher phenolic index (49.03 vs 25.67). Significant correlations between the wine spirits’ antioxidant activity, total phenolic index, ellagic acid, gallic acid, vanillin and syringaldehyde concentrations were observed, particularly in those aged using the alternative technology.Conclusion: Micro-oxygenation combined with staves resulted in higher accumulation of bioactive compounds and antioxidant activity, thus increasing wine spirit quality and adding value to the product.Significance of the study: These preliminary results show that the characteristics acquired by the wine spirit, coupled with those revealed by previous research and the promotion of faster and cheaper ageing, make the alternative technology a promising option for the industry.

Application of Functional Data Analysis and FTIR-ATR Spectroscopy to Discriminate Wine Spirits Ageing Technologies

Fourier transform infrared spectroscopy (FTIR) with Attenuated Total Reflection (ATR) combined with functional data analysis (FDA) was applied to differentiate aged wine spirits according to the ageing technology (traditional using 250 L wooden barrels versus alternative using micro-oxygenation and wood staves applied in 1000 L stainless steel tanks), the wood species used (chestnut and oak), and the ageing time (6, 12, and 18 months). For this purpose, several features of the wine spirits were examined: chromatic characteristics resulting from the CIELab method, total phenolic index, concentrations of furfural, ellagic acid, vanillin, and coniferaldehyde, and total content of low molecular weight phenolic compounds determined by HPLC. FDA applied to spectral data highlighted the differentiation between all groups of samples, confirming the differentiation observed with the analytical parameters measured. All samples in the test set were differentiated and correctly assigned to the aged wine spirits by FDA. The FTIR-ATR spectroscopy combined with FDA is a powerful methodology to discriminate wine spirits resulting from different ageing technologies.

Antioxidant and Mineral Composition of Three Wild Leafy Species: A Comparison Between Microgreens and Baby Greens

Wild plants may play an important role in human nutrition and health and, among them, many are the leafy species. We hypothesized that the wild greens could be profitably grown as microgreens and baby greens, specialty products whose market is increasing. We compared three wild leafy species (Sanguisorba minor Scop., Sinapis arvensis L., and Taraxacum officinale Weber ex F. H. Wigg.) harvested at the microgreen and baby green stages. Seedlings were grown hydroponically in a half-strength Hoagland nutrient solution under controlled climatic conditions. At harvest, the yield was assessed, and chlorophylls, carotenoids, anthocyanins, phenolic index, nitrate, and mineral elements were measured in the two types of product. The potential contribution to human mineral intake was calculated, and the possible risk due to the presence of metals potentially detrimental for health was estimated. Results showed that micro/baby greens of the studied wild plants achieved competitive yields and could contribute to the dietary intake of macroelements, microelements, and non-nutrient bioactive compounds. On the other hand, the wild greens showed high amounts of nitrate and traces of some metals potentially detrimental for health, suggesting the need for caution in the use of wild species for producing microgreens and baby leaves.

Influence of the micro-oxygenation dose and supplementation with oak staves of different potential of ellagitannin release on wine color and composition

Aliquots of a wine of Merlot were micro-oxygenated at two doses of oxygen (2.5 and 5.0 mg of O2/L.month) in the presence or not of oak staves of different potential ellagitannin release (PER) for three months. In general, micro-oxygenation increased the color intensity and stability probably because favor the formation of new pigments. The presence of staves increased the total phenolic index and the ellagitannin concentration, and this effect was higher when greater was the PER of the staves. Finally, the dose of microoxygenation only affects the concentration of total furanic compounds whereas the PER of the staves seems to determine the concentration of furanic compounds, volatile phenols and β-methyl-γ-octolactones.

Unravelling the effects of berry size on ‘Tempranillo’ grapes under different field practices

Small berries are considered to produce the best red wines as berry size determines the skin to pulp ratio and may affect wine composition. However, contrasting results have been reported about this postulate. In this context, the aim of this work was to assess the influence of berry size on grape compositional attributes in ‘Tempranillo’ grapevines under different irrigation, crop load and defoliation regimes. Grapes were collected from different experiments performed during three years in a ‘Tempranillo’ vineyard (Valencia, Spain). Grape size distribution was assessed and several traits were measured for each size category: number of seeds, seed and skin weight, total soluble solids, titratable acidity, pH, total phenolic index and anthocyanin concentration. Berry size exerted a significant effect on grape composition; smaller berries having higher sugars and anthocyanins concentrations. However, irrigation, crop load and defoliation also affected these compositional traits, producing greater berries with similar traits than those smaller, but coming from rain-fed and not defoliated treatments. Depending on the field practices applied, grape compositional attributes can be modulated for a given berry size. Therefore, wineries can use berry size classification for selecting those from a given size for making different wine styles.