'Modra frankinja' as a variety and varietal wine is becoming more and more recognisable in Slovenia, and most presented in Posavje winegrowing region. For the master thesis, in 2021 in Dolenjska district we studied the impact of technological measures on the grape and wine quality of 'Modra frankinja'. The study included five treatments: control (K), cluster thinning (RED), leaf removal (RAZ), double maturation raisonnée (DMR) and cane girdling (OBR). The impact of the measures was evaluated by analysing the content of primary and secondary metabolites in the grape and wine according to the treatment. The titratable acidity, pH, weight per 100 berries, CIRG, tone of colour of grape juice, total phenolic content of berry skins, intensity and tone of the wine colour, total phenolic content of wine and certain characteristics of the wine were not significantly different among the treatments. The significantly highest soluble solids contents (22.6 and 22.1 °Brix) and specific must densities (1.095 and 1.093 g/cm3) were measured in the grapes from RED and DMR vines. For production of high quality wine an appropriate measure is cluster thinning. Grape of K vines had the significantly highest total acidity (8.22 g/l). The significantly highest colour intensity (6.67) of the grape juice and content of total phenolics (132.70 mg/g) was found in the grapes from RAZ vines. The significantly highest CIRG index is from grapes of OBR vines. The significantly highest volatile acids content (0.90 g/l) was measured in wine from DMR vines, while significantly highest content of reducing sugars (2.0 g/l) in wine from RAZ vines. In one-year experiment between the technological measures there are no significant difference to achieve proper grape and wine quality, while many of the measurements and treatments show marginal significant differences. Due to the weather and microclimatic conditions it is not yet possible to establish a varietal ampelotechnics, the study should continue for at least one or two years.
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