Terroir aspects in development of quality of Egri bikavér

Commercial red wines use the malolactic fermentation process to ensure stability from a microbiological point of view. In this second fermentation, malic acid is converted into L-lactic acid under controlled steps.

Analytical methods for dating wines often rely on assessing anthropogenic and cosmogenic radionuclides, including 14C and 137Cs [1,2].

Farming management practices aiming at conserving soil moisture have been developed in arid and semiarid-areas facing water scarcity problems. Organic mulching is an effective method to manipulate the crop-growing microclimate increasing crop yield by controlling soil temperature, and retaining soil moisture by reducing soil evaporation. In this sense, the effectiveness of different organic mulching materials (straw mulch and grapevine pruning debris) applied within the row of a vineyard was evaluated on the soil and on the vine in a Tempranillo vineyard located in La Rioja (Spain). Organic mulches were compared with a traditional bare soil management technique (based on the use of herbicides to avoid weed incidence). Mulching coverages favourably influenced the soil water retention throughout all the grapevine vegetative cycle. However, the soil-moisture variation was not the same under different mulching materials, being the straw mulch (SM) the one that retained more water in comparison with grapevine pruning debris (GPD) based-cover. The changes of soil moisture in the upper surface layer (0–10 cm) were highly dynamic, probably due to water vapour fluxes across the soil-atmospheric interface. However, both, SM and GPD reduced these fluctuations as compared with bare soils. A similar trend occurred with soil temperature. Both organic mulches altered soil temperature in comparison with bare soil by reducing soil temperature in summer and raising it in winter. Moreover, the same buffering effect for the temperature on the covered soil also remains in the deeper layers. To conclude, we could see that organic mulching had a positive impact on soil-moisture storage and soil temperature and the extent of this effect depends on the type of mulching materials. These changes led to higher rates of photosynthesis and stomatal conductivity compared to bare soils, also favouring crop growth and grape yields.

Climate change has numerous detrimental consequences and creates new challenges for viticulture around the world. Transitory or constant high temperatures frequently associated with an excess of sunlight (UV) can cause a variety of physiological disorders, such as sunburn. Diverse environmental factors and the plant’s response mechanisms to stress determine the symptoms. Grapevine berry sunburn leads to a drastic reduction in yield, and may eventually decline berry quality. Consequently, this poses a significant risk to the winegrowers.

Environmental factors like soil and climate influence grape quality potential. Their impact is often mediated through vine water and nitrogen status. Depending on the color of the grapes (red or white) and the type of wine produced, the desired level of vine water and nitrogen status for optimum wine quality is different. Little investigation has been carried out concerning these factors and their potential influence on sparkling wine quality on two vintages. In this study vine water and nitrogen status were assessed at a very high density and related to grape composition and berry weight. Through statistical analyses, the major factors driving grape quality potential on Pinot noir in Champagne were highlighted.