Sulfur dioxide has been used in the wine industry for many centuries due to its antimicrobial and antioxidant effects. However, the problem is that SO2 is a major allergen and when consuming higher doses, health complications (such as headaches, stomach aches, asthmatic problems) may occur. It is therefore important to find a suitable substitute, or rather a supplement to this substance. One of the options is the use of saturated higher fatty acids (HFA). These substances naturally occur in nature and a small amount of them is formed by yeasts themselves during fermentation. Thanks to HFA the yeast cells´ lipid membranes are changed (their liquidity), resulting in cell degradation, slowing of metabolism and thus slowing down the fermentation until it is stopped. In this experiment, a mixture of HFA, octanoic, decanoic and dodecanoic acid, ratio 2:7:1, respectively, was used at doses of 5, 10, 20, 30, 40 and 60 mg/l, with two variants of the application SO2, 20 mg/l or 40 mg/l. The HFA residues, the corresponding ethyl esters and the influence on sensory properties of the wine were observed. The results of this experiment show (or HFA residues) that the more HFA is added, the more they are absorbed by the yeasts. At the same time there was a very slow esterification in time and thus a low influence on the aroma of wine. Sensory analysis showed the HFA dose of 20 mg/l as the limit from which we are able to recognize differences in HFA doses. There was also an influence of sludge particles. The longer the wine matures, the less sludge particles it contains, hence the HFA are bound on the yeast cells, and thereby their influence on wine sensory is reduced.
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:424678 |
| Date | January 2017 |
| Creators | Chvalinová, Klára |
| Source Sets | Czech ETDs |
| Language | Czech |
| Detected Language | English |
| Type | info:eu-repo/semantics/masterThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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