QUALITATIVE CHARACTERISTICS OF THE WINE OBTAINED FROM WHITE FETEASCA GRAPES' VARIETY, DERIVED FROM WINE-GROWING CENTRE OSTROV, ALONG THREE SUCCESSIVE CROPS

Abstract

There have been analysed the physical and chemical characteristics (d 20 , alcohol % vol., total dry extract mg/l, free sugar g/l, unreducing extract g/l, total acidity g/l C 4 H 6 O 6 , free SO 2 mg/l, total SO 2 mg/l) definitive for the wine quality made from the White Feteasca grapes'variety, in three successive years: 2004,2005 and 2006. The climatic peculiarities of the forenamed years, determined the appearance of some quality statistic differences, as follows: d 20 20 diminished significantly in 2006 comparative to the precedents years, the quantity of alcohol increased distinctly significant in 2006 comparative to 2004 and 2005, the total dry extract and unreducing extract diminished distinctly significant in 2005 against 2004, total acidity diminished very significantly in 2006 against 2004, respective 2005 and the total SO 2 content was significantly and very significantly lower in 2006 against 2004, respective 2005. There have been observed no differences between the annual crops, concerning the parameters: free sugar and free SO 2. Conclusevely, the wine from 2006 was stronger, more dry and less sulfiteted, comparative with wines from 2004 and 2005.

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Lucrari stiintifice - Management, Inginerie economica in agricultura si Dezvoltare rurala, ISSN, vol 9, 2008.
QUALITATIVE CHARACTERISTICS OF THE WINE OBTAINED FROM
WHITE FETEASCA GRAPES’ VARIETY, DERIVED FROM WINE-
GROWING CENTRE OSTROV, ALONG THREE SUCCESSIVE
CROPS 2004, 2005 AND 2006
PARTICULARITĂŢI CALITATIVE ALE VINULUI OBTINUT DIN SOIUL
FETEASCA ALBA, PROVENIT DIN CENTRUL VITICOL OSTROV, PE
PARCURSUL A TREI RECOLTE SUCCESIVE 2004, 2005 SI 2006
Culea Rodica- Elena *, Tamba-Berehoiu Radiana*, Popa Nicolae-Ciprian**
*University of Agronomic Sciences and Veterinary Medicine of Bucharest
**Center of Microbial Biotechnology BIOTEHGEN - Bucharest
Abstract
There have been analysed the physical and chemical characteristics (d20 , alcohol % vol., total dry extract
mg/l, free sugar g/l, unreducing extract g/l, total acidity g/l C4H6O6, free SO2 mg/l, total SO2 mg/l) definitive for
the wine quality made from the White Feteasca grapes’variety, in three successive years: 2004,2005 and
2006. The climatic peculiarities of the forenamed years, determined the appearance of some quality statistic
differences, as follows: d2020 diminished significantly in 2006 comparative to the precedents years, the
quantity of alcohol increased distinctly significant in 2006 comparative to 2004 and 2005, the total dry extract
and unreducing extract diminished distinctly significant in 2005 against 2004, total acidity diminished very
significantly in 2006 against 2004, respective 2005 and the total SO2 content was significantly and very
significantly lower in 2006 against 2004, respective 2005. There have been observed no differences between
the annual crops, concerning the parameters: free sugar and free SO2. Conclusevely, the wine from 2006
was stronger, more dry and less sulfiteted, comparative with wines from 2004 and 2005.
Key words: White Feteasca, quality, physical and chemical characteristics, statistic differences
INTRODUCTION
The commercial company S.C. OSTROVIT S.A. belongs to the wine-growing centre
Ostrov from Ostrov Vineyard, placed in the region of the Danube Terrace. The type of the
soil from Ostrov Vineyard is the chernozem, with argillaceous – sandy fibber, the soil’s
reaction being alkaline. The temporal character of the precipitations determined the
droughty specific of the zone, affecting the productive potential of the wine grapes
cultivated here. The years 2004 and 2005 were exceptions, because the precipitations’
amount was more over the annual average registered so far (the wine obtained having a
less content of sugars and a higher acidity). Instead, 2006 was less rainy.
This study recommends a comparative characterization of the dry wine’s quality,
obtained from the White Feteasca grapes’variety, made by S.C. OSTROVIT S.A., in the
production years: 2004, 2005 and 2006. The physical and chemical analysis emphasis the
wine’s peculiayties, in the preceding stage of bottling and commercialization. The White
Feteasca wine is characterized through harmony and complex flavour, having the alcohol
content between 11,0 and 12,6 % and being registered in the category of superior wines
[1,5,6].
MATERIAL AND METHOD
There have been taken for analysis samples of unbottled wine, from the White
Feteasca grapes’variety, three successive years, as follows: 10 repetitions in 2004, 13
repetitions in 2005 and 10 repetitions in 2006. There have been analysed the following

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quality parameters of the wine: d2020 (picnometric method STAS 6182/8-71), alcohol %
vol. (picnometric method STAS 6182/6-70), total dry extract mg/l (densimetric method
STAS 6182/9-80), free sugar g/l (iodometric method STAS 6182/18-81), unreducing
extract g/l, total acidity g/l C4H6O6 (titrimetric method STAS 6182/1-79), free SO2 mg/l
(iodometric method STAS 6182/13-72) and total SO2 mg/l (iodometric method STAS
6182/13-72) [2,3,4,7]. The obtained results were statistical processed using the
professional program COHORT.
RESULTS AND DISCUSSION
The first table distinguished the quality parameters’ values of the White Feteasca dry
wine, concerning 2004 year. We also noticed the normal values, of all analysed
parameters, mentioned in the scientific literature.
Table 1
The variability estimates of the physical-chemical parameters,
according to 2004 crop (n =10)
The majority of the values are placed in normal limits. The total dry extract gets a bit
over the limit of 24 g/l, while the free sugar situates to the middlle of the admitted value for
the dry wines, circumstance which determines the slightly increase of the unreducing
extract. The sulphitation degree did not overstep the admitted limits.
There are noticeable, in the second table, the averages’values of the wine’s quality
parameters, obtained from the 2005 year crop.
Table 2
The variability estimates of the physical-chemical parameters,
according to 2005 crop (n =13)
Parameter
X sx

s
CV %
d2020 (g/ml)
0.994 ± 0.001
1.0442E-06
0.102
Alcohol (vol %)
11.115 ± 0.182
0.033
1.637
Total dry extract (g/l)
22.123 ± 2.244
5.037
10.143
Free sugar (g/l)
2.431 ± 0.844
0.714
34.718
Unreducing extract (g/l)
19.738 ± 1.815
3.294
9.195
Total acidity (g/l C4H6O6)
5.351 ± 0.410
0.168
7.662
Free SO2 (mg/l)
40.000 ± 0.000
0.000
0.000
Total SO2 (mg/l)
136.846 ± 17.296
299.141
12.638
In 2005, all the quality parameters showed values situated into admitted limits,
without exceptions. The behavior of the quality parameters of the wine, for 2006, are
presented in the table 3.
Parameter
Normal limits
X sx

s
CV %
d2020 (g/ml)
0.983-1.003
0.994 ± 0.00046
2.1655E-07
0.046
Alcohol (vol %)
10.5-12.5
11.140 ± 0.206
0.042
1.849
Total dry extract (g/l)
18-24
24.340 ± 1.040
1.082
4.274
Free sugar (g/l)
Maximum 4 g/l
2.170 ± 0.177
0.031
8.110
Unreducing extract
(g/l)
Dry extract -
Free sugar
22.170 ± 0.980
0.962
4.420
Total acidity
(g/l C4H6O6)
4.5-9
5.846 ± 0.254
0.064
4.000
Free SO2 (mg/l)
Maximum 50
40.000 ± 0.000
0.000
0.000
Total SO2 (mg/l)
Maximum 200
133.000 ± 14.621
213.777
10.933

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Table 3
The variability estimates of the physical-chemical parameters,
according to 2006 crop (n =10)
Parameter
X sx

s
CV %
d2020 (g/ml)
0.9930 ± 0.001
1.384E-06
0.110
Alcohol (vol %)
11.910 ± 0.536
0.288
4.500
Total dry extract (g/l)
22.841 ± 2.348
5.514
10.279
Free sugar (g/l)
1.880 ± 0.907
0.823
48.244
Unreducing extract (g/l)
20.150 ± 3.299
10.887
16.372
Total acidity (g/l C4H6O6)
5.319 ± 0.202
0.041
3.797
Free SO2 (mg/l)
35.700 ± 6.848
46.900
19.182
Total SO2 (mg/l)
115.700 ± 14.221
202.233
12.290
All the quality parameters’ values were situated in normal limits, which have been
described in scientific literature, however we noticed a notable diminution of the free sugar
content, probably due to prolongation of the fermentation and transformation of the sugar
in alcohol. Otherwise, the wine obtained in 2006 is stronger (alcohol vol % ) than the wine
obtained from the crops of the 2004 and 2005 years.
The meaning of averages’ differences (test t) emphasis the impact of the climatic
factors from successive years (2004, 2005, 2006), over the quality of the dry wine White
Feteasca (table 4).
Table 4
The meaning of averages’ differences (t test) for all the
quality parameters, between the annual crops
Parameter
Pears
Average (a)
Average (b)
t
2004 (a) – 2005 (b)
0.9940
0.9940
0.000
2004 (a) – 2006 (b)
0.9940
0.9930
2.886*
d2020 (g/ml)
2005 (a) – 2006 (b)
0.9940
0.9930
2.377*
2004 (a) – 2005 (b)
11.140
11.115
0.309
2004 (a) – 2006 (b)
11.140
11.910
4.238**
Alcohol (vol %)
2005 (a) – 2006 (b)
11.115
11.910
4.491**
2004 (a) – 2005 (b)
24.340
22.123
3.149**
2004 (a) – 2006 (b)
24.340
22.841
1.846
Total dry extract
(g/l)
2005 (a) – 2006 (b)
22.123
22.841
0.745
2004 (a) – 2005 (b)
2.170
2.431
1.083
2004 (a) – 2006 (b)
2.170
1.880
0.992
Free sugar (g/l)
2005 (a) – 2006 (b)
2.431
1.880
1.501
2004 (a) – 2005 (b)
22.170
19.738
3.817**
2004 (a) – 2006 (b)
22.170
20.150
1.855
Unreducing
extract (g/l)
2005 (a) – 2006 (b)
19.738
20.150
0.382
2004 (a) – 2005 (b)
5.846
5.351
3.349**
2004 (a) – 2006 (b)
5.846
5.319
5.143***
Total acidity (g/l
C4H6O6)
2005 (a) – 2006 (b)
5.351
5.319
0.245
2004 (a) – 2005 (b)
40.000
40.000
0.000
2004 (a) – 2006 (b)
40.000
35.700
1.698
Free SO2 (mg/l)
2005 (a) – 2006 (b)
40.000
35.700
1.698
Total SO2 (mg/l)
2004 (a) – 2005 (b)
133.000
136.846
0.564

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2004 (a) – 2006 (b)
133.000
115.700
2.682*
2005 (a) – 2006 (b)
136.846
115.700
3.132***
The density of the wine (figure 1) was meaningful smaller in 2006 against 2004
(2.886*) and 2005 (2.377*).
0.994
0.994
0.993
0.9924
0.9926
0.9928
0.993
0.9932
0.9934
0.9936
0.9938
0.994
Density (mg/ml)
2004 2005 2006
Figure 1. The meaning of averages’ differences (t test)
for wine’s density d2020
The percent of alcohol (in vol %) was distinctly meaningful increased in 2006,
comparative to 2004 (4.238**) and 2005 (4.491**). However, the content in free sugar did
not differ meaningful between the three studied crops, being even little reduced in 2006,
but probable fermented a pretty long while (figure 2).
11.91
11.14
11.115
10.6
10.8
11
11.2
11.4
11.6
11.8
12
2004 2005 2006
Alcohol (vol %)
Figure 2. The meaning of averages’ differences (t test)
for wine’s content in alcohol
The unreducing extract (figure 3) was distinctly meaningful increased in 2004
comparative to 2005 (3.817**), which explains the distinctly meaningful increase of the
total dry extract in 2004 against 2005 (3.149**).
0
5
10
15
20
25
30
Unreducing
sugar (g/l)
Total dry
extract (g/l)
2004
2005
2006
Figure 3. The meaning of averages’ differences (t test)

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for wine’s unreducing extract and total dry extract
The total acidity (figure 4) was distinctly meaningful increased in 2004 comparative to
2005 (3.349**) and very meaningful increased in 2004 against the crop 2006 (5.143***).
The wine of the crop 2004 was a dry wine and sourish at the same time. The acidity did
not differ meaningful between the wine of the crops 2005 and 2006.
5.846
5.351
5.319
5
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
Total acidity (g/l C4H6O6)
2004 2005 2006
Figure 4. The meaning of averages’ differences (t test)
for wine’s total acidity
The quantity of free SO2 (figure 5) did not present meaningful differences between
the samples of wine derived from the three forenamed years. On the other hand, the
quantity of total SO2 was distinctly meaningful increased in 2004 comparative to 2006
(2.682*) and very meaningful increased in 2004 comparative to 2006 (3.132***). The
explanation dues to the abundant sulphitation of wine, coming from 2004 and 2005 (rainy
years), with the intention of breaking the intense growth of the mouldes developed in the
ingathering’s crop period.
133
136.846
115.7
105
110
115
120
125
130
135
140
Total SO2 (mg/l)
2004 2005 2006
Figure 5. The meaning of averages’ differences (t test)
for wine’s total SO2
CONCLUSIONS
 The tehnological processes of wine preparation were guided so that, no matter the
processing year, all the parameters were framed between the limits established by the
quality standards.

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 The wine of the year 2004 was the most acid, having in consequence a pronounced
sourish taste and an enough increased total dry extract (a little more above the superior
limit of the range).
 The wine of the year 2005 had the most sweet taste, comparative to the wines from
2004 and 2006 (yet ranging among the category “dry wine”), the other parameters having
intermediary values compared to 2004 and 2005.
 The wine of the year 2006 was the strongest (content in alcohol) and the most dry (small
content of sugar).
 The total sulphitation, having increased values in the rainy years (2004 and 2005), did
not affect the dry wines’ quality, but maintained in optimum limits the fermentation flora’s
concentration.
The commercial company S.C. OSTROVIT S.A. produces dry wines of superior
quality, due to the systematic control over the production tehnological proceedings. In this
sense, the climatic differences, to which the crops coming from forenamed years had been
submitted, did not introduce fundamental changes in the wines’ quality, even if they
manifest peculiar to the level of the certain physical-chemical parameters.
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