Vol 3 (1) 2011 - UBM :: Departamentul de Chimie-Biologie

Y. Vagelas , M. Zold, L. Giurgiulescu, Study on Tokaj Wine contamination with different type of moulds
Figure 8. Variation of ash on the three different types of wine
After 4 days of incubation at 25 0 C,
individual fungal colonies were sub-cultured
under the same condition, and pure cultures
were obtained. Microscopic identification of
each the type of fungi was performed.
The next analysis were conduct for wine
samples:
a) Total Acidity
The method consist in neutralizing the
acidity with solution of NaOH 0.1 N, using
bromothymol as an indicator. Acidity was
expressed as tartric acid g/L [4, 5, 6 ].
b) Total SO2
The method consists in titration the
sample to be analyzed with solutions of
NaOH and H 2 SO 4 and the iodomoetric
titration of the released sulfure dioxid from
its combination with sugar and aldehydes in
acidic medium. The results were expressed
as SO 2 mg / L [4, 5, 6].
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c) Ash
The method consists in evaporating the
wine to be analyzed on water bath and
calcination the dried residue in an electric
furnace at temperature range of 450-550 0 C.
[4, 5, 6].
3. Results and discussions
Three types of fungus were identified on
the 12 analyzed wine samples: Penicillium
chrysogenum, Penicillium expansum and
Phanerochaete chrysosporium.
According to Figures 6 - 8 the healthy
wine is within the normal values. The color
of the wines did not changed at all.
The Figure 6 indicates the variation of
total acidity different for each type of fungi.
Penicillium chrysogenum lowers the value of
acidity for each type of wine comparing to
healthy wine, so this means that the wine
was not contaminated, the wine is not
acidulated. Penicillium expansum and
Phanerochaete chrysosporium increase the