Sulfur dioxide plays an important role in wine production, as a antimicrobial, antioxidant, color stabilizing and preserving varietal aroma. Nowadays, a lot of attention is paid to the amount of SO2 added. Excessive concentrations of SO2 have negative effect on sensory properties of wine, as well as on consumer’s health. In the diploma thesis we studied the content of sulphur dioxide in white wines of local producers of the wine growing region of Podravje, districts Oplotnica and Rogaška Slatina. The purpose of the task was to determine the amount of sulphur dioxide in all three forms (free, bounded and total) and to evaluate the results. Both methods for the determination of SO2 in wine were performed with iodometric titration – the Ripper method and the Rebelein distillation method. A FTIR analysis was also performed to determine certain parameters (sugars, acids, alcohol, extract…). Based on the obtained results, we expected quite a lot of variability between the samples, which turned out to be the case. The samples were well protected in most cases, given the proportion of the molecular form of SO2, and the ratio between free and total sulphur dioxide proved to not be ideal in most cases. The analytical methods were comparable to each other with minor deviations.
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