Recently, the interest in methyl jasmonate (MeJ) has increased in viticulture due to its effects on the synthesis of phenolic secondary metabolites in grapes, especially of anthocyanins, flavonols, and stilbenes derivatives, naturally occurring or synthesized, in berries in response to MeJ application to grapevines. These metabolites help to define sensory characteristics of wines by contributing to their color, flavor and mouthfeel properties, and to derive potential beneficial health effects due to their consumption. This review offers an overview of the importance of these phenolic compounds in grape and wine quality, in association with the MeJ supplementation to grapevines, and also considers their natural biosynthesis in grapes. On the other hand, this review describes the adaptation mechanisms induced after the grapevine elicitation. In addition, this report addresses the effects of MeJ over other aspects of Vitis immunity and its association with phenolic compounds and summarizes the recently published reports about the effects of exogenous MeJ applications to grapevines on grape and wine quality.
Hyper-arid regions are characterized by extreme conditions for growing and lack of water (<100 mm annual rainfall average), where desertification renders human activities almost impossible. In addition to the use of irrigation, different viticultural strategies should be taken into account to face the adverse effects of these conditions in which rootstocks may play a crucial role. The research aim was to evaluate the effects of the rootstock on yield, vigor, and petiole nutrient content in Syrah grapevines growing under hyper-arid conditions during five seasons and compare them to ungrafted ones. St. George induced lower yield than 1103 Paulsen. Salt Creek induced higher plant growth vigor and Cu petiole content than ungrafted vines in Syrah, which was correlated to P petiole content. However, Salt Creek and St. George rootstocks induced an excess of vigor in Syrah according to Ravaz Index. Rootstocks with V. berlandieri genetic background should be used in Syrah growing under hyper-arid conditions to maintain adequate levels of plant vigor and to avoid deficiencies or toxicity of macro and micronutrients.
(1) Background: Degradation of soils and erosion have been described for most of the soils presented along the Maule Valley. Organic and integrated management promotes agroecosystem health, improving soil biological activity. Due to this, the aim of this research was to study the effect of organic, integrated, and conventional management on the productive, oenological and soil variables of a vineyard cultivated under semiarid conditions during 5 consecutive seasons; (2) Methods: Yield, grape and wine oenological, and soil physicochemical parameters were evaluated. Bioclimatic indices were calculated in the studied seasons; (3) Results: Conventional management allowed to improve yield and the number of bunches per vine compared to organic management. However, this latter enhanced mineral nitrogen and potassium content in soil. Based on bioclimatic indices, heat accumulation improved number of bunches per plant and most of the soil physicochemical parameters; (4) Conclusions: Organic management improved the accumulation of some microelements in soils at the expense of yield. Organic matter decreased along the study was carried out. Season was the conditioning factor of the variability of most of the studied parameters, while the interaction between season and type of management affected soluble solids, probable alcohol and pH in grapes, and total polyphenol index and pH in wines.
26 February 2021 in IVES Technical Reviews, vine and wine
Reverse osmosis and spinning cone columns are promising techniques for reducing alcohol content in wines. Most wineries are only interested in reducing ethanol content by one or two alcoholic degrees in order to obtain more balanced wines. However, new consumption habits and alcohol safety laws have induced the wine industry to produce new beverages from non-alcoholic or low alcohol wines. The aim of this study was therefore to evaluate the impacts of the dealcoholisation of wines by reverse osmosis and spinning cone columns on the sensory characteristics of the final product.
Background: Wine antioxidants are linked to cardiovascular disease prevention, thus are highly valued by the healthy food market. The dehydration process removes alcohol and water from wine and allows it to extend its shelf life, while encapsulation can help preserve physical-chemical and antioxidant properties. Moreover, information on the effect of wine drying and encapsulation on non-anthocyanin phenolic compounds is limited in the literature. Methods: Listan Prieto and Syrah (Vitis vinifera L.) wines were dehydrated and converted into powder by freezing and spray drying. Powdered wines were subjected to water activity, pH, soluble solids, color, and phenolic compounds analysis. Results: Freeze-drying process produced powdered wines with higher pH than the spray-drying process. Powdered wines made by these processes presented similar water activity and soluble solids. Powdered wines did not show statistical differences in trans-resveratrol, hydrocinnamic acids, phloretin, kaempferol, and quercetin content according to their dehydration process. In addition, powdered wines significantly concentrated hydrocinnamic acid and quercetin when compared to non-dealcoholized and dealcoholized wine samples. Conclusions: The results suggest that the dehydration process does not negatively modify the characteristics of the wine, and it retains a significant concentration of phenolic compounds. Therefore, powdered wines have an interesting potential to be used as a natural source of antioxidants for food supplementation.