ISSN 0253 - 6749MISCELLANEOUS REPORTS 16

COMPOSITION OF CYPRUS WINES

T. S. Myrianthousis, R. Symeon, and D. Hadjidemetriou

AGRICULTURAL RESEARCH INSTITUTE MINISTRY OF AGRICULTURE AND NATURAL RESOURCES

NICOSIA CYPRUS

DECEMBER 1984

COMPOSITION OF CYPRUS WINES

T. S. Myrianthousis, R. Symeon, and D. Hadjidemetriou

SUMMARY

Constituents of commercial and experimental wines were determined and maximum-minimum values occurring most often in wines of ordinary quality have been tabulated. Maximum-minimum values are given for 43 analyses on 4 wine types: Dry while, dry red, Sherry type, and Commandaria.

INTRODUcnON

Chemical analysis of wines is a nonnal procedure for quality evaluation and for quality control. At all stages of wine making, certain constituents of grapes, musts and wines have to be measured. A course measurement of the sugar content of· grapes is taken by growers using the Baume hydrometer. A t the winery, the Baume reading of the fennenting must is recorded daily in order to follow and control the course of alcoholic fennentation. Even at the smaller wineries a minimum of analyses have to be conducted in order to ensure continuity of produc­tion of sound wines. Such analyses could be limited to alcohol, pH, sulphur dioxide, reducing sugar and volatile acidity or they could include more compli­cated analyses. Nonnally analyses conducted at wineries or for wine quality control are not published. They are intended for use in connection with production and marketing of individual lots of wines.

Research laboratories are normally the sources of data on wine analysis, and tables of results are often published in scientific journals (Yokotsuka and Kushida, 1983). Such tables, however, are confined to specific analyses directly related to very narrow fields of investigation. Analyses given in most tables are normally limited to less than ten consituents. Fornachon (1963) gives tables of analyses of twenty constituents, while tables on general wine analysis giving the maximum-minimum values of a number of constituents of wines from different regions are published in oenology textbooks (Amerine and Cruess, 1960).

The importance of the various constituents, and their concentrations in commercial wines are given under Laboratory procedures Jor enoLogists (Amerine, 1960). Methods of analysis of wines are also described. Official methods of analysis are the

most accurate but, in most cases, they are tedious and time consuming (A.O.A.C., 1975). They are mainly intended for quality 'control and for con­sumer protection especially in cases where subst­ances foreign to the wine are suspected. For most analyses of £!lusts and wines, international methods of analysis give both precision and speed, prgvided that the necessary equipment is available (Kourakou, 1971). Choice of methods of analysis is given in Recued des methodes internationales d' anaLyse des vins (O.LV., 1978). In most cases three methods of analysis are given: La methode de niJerence, which is the most accurate but labori­ous, La methode usuelle, which is rapid and rela­tively accurate, and La methode rapide, which is the least time consuming. Wineries normally prefer La methode rapide which is satisfactory for routine vinifacation purposes. For customs purposes La methode usuelle is nonnally followed, .while for consumer protection, where traces of certain ele­ments have to be detected, the methode de refer­ence is used.

Analyses of Cyprus wines are conducted by the four major wineries, by the Department of Agriculture for excise control, by the State General Laboratory for consumer protection, and by the Agricultural Research Institute for experimental vinifications.

[n the course of research work in viticulture and oenology certain consituents of grapes and wines were detennined for the evaluation of experimental results. For comparison purposes, similar detenni­nations were conducted on bulk processed commer­cial wines of ordinary quality. Such wines had been produced almost exclusively from the red grape vari­ety Mavro, which consitutes 80% of the total grape production of Cyprus (Vryonides, 1976). The vari­

ety Mavro is suitable for the production of dry wines when grapes are ripe, and for the production of sweet wines when grapes are mature. In addition to red wines, it is possible to produce white wines from Mavro grapes by separating the juice from the skins immediately after pressing. For the production of red wines the crushed grapes are fennented on the grape skins for at least four days for the red colour of the skins to be imparted to the wine.

Since results of analyses of Cyprus wines have never been published, this work was intended for the detennination of the maximum-minimum values of a number of consitutents of ordinary quality com­mercial wines.

MATERIALS AND METHODS

Analyses were conducted on ordinary quality, low priced commercial wines, which had been produced almost exclusively from the grape variety Mavro. Such wines had been fennented in 40m3 open ce­ment tanks, they were aged for six months in oak barrels and were kept in wooden vats for six more months before bottling.

Samples of the wine types Dry White, Dry Red, Sherry and Commandaria were taken from the bottling line from each of four wineries. They were then taken to the State General Laboratory for chemical analysis.

Methods of analysis used for the various detenni­nations were les methodes usuelles, as given by L' Office International de la Vigne et du Yin in the 1978 edition of the Rewed des Methodes 1([­ternationales d' Analyse des Vins.

RESULTS AND DISCUSSION

Analytical results were expressed in terms nor­mally employed by winemakers rather than in the form recommended by L' Office International de la Vigne et du Yin. The overall maximum-mini­mum values of analyses of all four wines and maxi­mum-minimum values of analyses of each wine type are given in Table 1.

Wine quality as graded by organoleptic examina­tion has to be supported by laboratory detennina­tions. All wine samples used for chemical analyses had been graded by organoleptic criteria as ordinary

quality commercial wines (vin ordinaire). Samples were true to label and representative of four wine types: dry white, dry red, sherry, and commandaria. Chemical analysis showed that values of the various constituents were within the limits to be expected for each wine type. Furthennore, tests for the pre­sence of substances foreign to the wine were nega­tive, which indicates that wines had been produced from the juice of fresh grapes, and no prohibited substances had been used. The only preservative used was S02, which is internationally accepted and used by all winemakers. The ratio among the vari­ous constituents of wines and the concentration of each consituent, give an indication of wine quality, method of vinification and assurance to consumers that wines contain only those substances which are present in grapes and/or result during the course of alcoholic fennentation and wine ageing. The signifi­cance of the various analyses may be summarized as follows:

The pH value indicates the actual acidity; wines of a low pH value are more resistant to disease than similar wines having higher pH values_ Amerine (1960) recommends that table wines should have a pH of not over 3.4 and dessert wines not over 3.8. Our results gave maximum pH values of 3.05 for table wines (dry white,dry red) and 3.71 for dessert/ wines (sherry, commandaria)

Electrical conductivity is a measure of the con­centration of inorganic and organic electrolytes, i.e. it is an approximate measure of soluble salts. Max­imum-minimum values were within the limits to be expected. Differences between wine samples of the same type were greater than differences among the four wine types.

The refractive index is a measure of the content of soluble solids, and specific gravity is a measure of the density of the solution as affected by sugars and acids, which are heavier than water, and of alcohol, which is lighter than water. As expected, values for dry wines (dry white, dry red, sherry) were lower than for the sweet wine commandaria.

Total soluble solids were lowest in dry white wines, higher in dry red wines, which may be attri­buted to tannin and colouring matter, and highest in commandaria, which contains sugars. For sherry, values were variable. Similarly, values for ash and alkalinity of ash were low for dry white wines, higher for dry red wines, variable for sherry, and highest for commandaria.

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Table I. Minimum·maximum va lues of constiluenls of four wine types.

Dry while Dry red She r ry Commandar l 3 All win~s

Min. MaJl. Min. M .... Min. Ma. Min. MaJl. Min Mal.

A n"'Y\I~

pH 108 1.87 2.90 ).05 1.85 ).)~ ).23 J.71 lOB ).7J (onduel lvi, y. micromhOSolcm 1250 17~0 1830 2100 1b40 19~0 1100 1800 1100 2100 RelraCliv( lode. 31 10°C 1.3411 1.)4)5 1.)4]1 1.3441 I.w..o 1.)470 1.)001 1.3 78) 1 )421 1.)783

Spcciflc Gravity 31 I~ ~0c. glcm) 0.990 0.994 0993 0.995 0985 0.991 1.05~ 1.075 0.990 1.075 T0101 ,ol;d,. gil 14.8 I~.O 22.2 2.5.3 17.0 29 ~ 1840 2.1.0 14.8 241.0 A,h. gil 1.32 1.92 1.8' 291 1.80 I. 7~ 2.42 3.7. 132 3.74 Allal;n;ly 01 .,h ., K 1COJ. gil 08 1.3 1.1 1.8 0.8 I ~ 1.9 ] . .J 0.8 2.4 T0101 acid;ly as Tanaric. gil ~O ~.1 5.3 6.5 , ~ ~ 1 4.1 ~ 3 4 5 6.5 Vol,uilc aCldllY as Acelic. gJ I 0.5 0.1 0.5 0.1 0.' 0.8 o9 1.1 0.4 1.1

fiJlcd acidily a~ Tanarj(. gil 4.] ~ 0 4.0 B ).1 4 9 ).~ .0 ).5 5.9 Tanaric acid. gil 1.0 U 2.0 1.5 09 1.9 1.1 2 0 09 2.5 Malic a<;d. gI I 1.1 21 1.& 18 1.1 25 1.0 11 1.0 18 Laclle acid. gil Iraas 0.05 . HaCc} 0.40 Haecs 0.)0 001 o ]0 "aces 04 Curic aCId. gil Iraen tracn Traces Haces Haces

Alcohol. % vlv 11.3 1:.3 II.' 11.3 180 18.8 15. I 100 II 3 18.8 Melhanol. gil 0005 0.01 0.014 0.30 .0 II o I' 0.09 0.11 0005 0.]1

1'1 • propanol. gil 0.0) 0.00 0.0) 0.11 0.0) 0.08 0.10 0.1' o03 0./4 00· bulyl .llcohOI gil 0008 0.020 0.008 0.015 0010 0011 0.010 0.011 0.008 0.020 /JO . amyl al(o'"'ol. gil 0.007 0018 0.008 0.010 0001 0.010 0000 0.012 0.006 0.018 Clycer;n. gil 3. I 8.' 4.9 6.6 ~.o 10 1.0 0.1 1.0 84 Aldehyde>. ppm 10 )() 10 30 10 138 11 )] 10 138 ESlers (Ethyl Ace,('IIc). ppm 11 ) I 10 10 19 )0 40 o~ 10 65 TOlal sugao. gil O.~ • 0 o.~ ).8 o.~ 8.5 100 19) o5 19) Reducing sugar~. gil 05 J8 O.~ ).7 O.~ U In 11J 0.5 11J Glucmr: (Aldo",). gil o I J , 0.2 ) 0 01 8 ~ 00 86 O? 80 Sulphu' dlQ.l ide. ppm 155 100 111 201 87 212 01 18) 01 200 Pres,crvalivo (orhel Ihan S°l) NIL NIL I'IIL NIL NIL Inremily 01 col(lVI 00" o I. ) )0 ,.15 o IJ 0.• 1 I.l~ 00~ 006 0.0~

Artirlcial coioul I'IIL I'IIL I'IIL NIL I'IIL TOIal Nlllogen. gil 007 OJ? 0.01 0.10 0.1' 011 010 O.J~ 007 0.4~

PfOlcin~ INXo I~). gil

Nlf"t1e~ 11'103 ). ppm

o , 1.0

08 0.1

0.' I.J

1.0 7.8

09

1.9 I 3

'.8

1.0

".1

: 8

8 3 o " 1.1

1.8 8.)

Pho,ph"" (Pia). ppm 110 110 90 105 181 130 )O~ 31~ 90 )75 Sodium. ppm 18 J7 15 58 )9 09 1.\ 1) II 1J P013~~jum. ppm 136 1510 83~ 9~9 ~9' 1019 118 1300 ~ Jh I~ 10 Calcium. ppm )5 II <I bO )1 )9 18 )6 18 00 Magne~ivm . ppm b-l 1/9 19 III 11 J7 10 1l.1 :0 09 Mangan(sc. ppm 019 III 0.1.1 o8~ I'IIL 0): NIL 0.J8 NIL O.8~

COPP« . ppm 0.05 U9 0.10 1.09 0.25 1.84 0)4 1 81 ~ 01 1.81 Iron. ppm ] 55 0()4 1.00 8.19 0.)2 J.I~ 1.08 .1 19 3) ~. 19 linc. ppm o38 I.J) 0.'0 1.90 039 I I~ o. ~" I 4I II.)~ I."J Lead. ppm NIL O.? NIL 0.1 0.1 0.) NIL OJ I'IIL 0.)

Ar!lcnic. ppm NIL 0.1 NIL NIL 11.1 NIL NIL 11.1

Fixed acidity and tOlal acidity were within the de­ The alcohol content was within the desirable

sirable limits for all wine types. ·The ratio of malic to limits for each wine type. Methanol is undesirable,

tartaric acid, however, was high. This could be due but values detected were negligible and comparable

to the fact that grapes were picked before they had to values detected In most wines elsewhere

reached physiological maturity. The ratio for com­ (Amerine and Cruess, ]960). The higher alcohols mandaria, where grapes were picked near maturity, n - propanol, Iso - butyl alcohol, and iso - amyl was not so high. The low lactic acid content com­ alcohol were detected in very small amounts, which pared to the high malic acid is an indication that could not have any adverse effect on the aroma of malolactic fennentation did not occur in any of the the wines. wines. Only traces of citric acid could be detected, Glycerin is considered a quality factor, and wines which assures that citric acid had not been added to of a higher glycerin value are of beller quality. the wines. Volatile acidity is an indication of bacte­ Amerine and Cruess (1960) give minimum values of rial spoilage of wines, and low values indicate sound 3.0 gil. Our results, except for one sample, gave val­wines. Minimum-maximum values were 0.4-1.2, ues of3.] - 8A gIl. Small amounts of aldehydes and which is quite acceptable. esters are contained in wines. A high aldehyde con-

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tent was measured in one sample of sherry, which proves that it was a flor sherry. Organoleptically it was superior to all other samples of sherry type wIne.

Total sugars, reducing sugars and glucose are a basic requirement for sweet wines (commandaria) but should not be detected in amounts greater than 10-20 ppm in dry wines (dry white, dry red, sherry). The maximum sugar content in the dry wines tested was 8.5 gil. The difference between total sugars and reducing sugars should be small. If it is big, it is an indication that sugar was added to the must or to the wine. The value for glucose is expected to be about half of the total sugars, the rest being fructose. Our results show that all sugar in the wine came from grapes.

Sulphur dioxide is the only legidly permitted anti­septic and preservative for wines. It ensures a bacteria-free fermentation and the preservation of sound wines It is used, or abused, by every winemaker in every country, since it also ensures that the winemaker will continue to hold his job! In other words, use of S02 prevents losses from wine spoilage. Legally permitted limits In various countries vary from 150 to 450 ppm (Amerine, 1960). Preservatives other than S02 were not de­tected in any of the wines. Total S02 concentration in the wines tested was 61-266 ppm. However, amounts greater than 200 ppm are undesirable.

The intensity of colour measured was representa­tive of the visual colour for each type of wine. Tests for the detection of artificial colour, which is illegal, were negative.

Proteins and nitrates occur in small amounts in wines. They normally undergo a number of changes during alcoholic fermentation, and the development of odorous materials has often been associated with biochemical changes of nitrogenous compounds. The wines analyzed contained only small amounts of nitrogen, proteins, and nitrates and they were biologically stable.

Phosphates, sodium and calcium are normal con­stituents of wines. Our results are in agreement with values obtained elsewhere (Amerine and Cruess, 1960). Similarly, small quantities of magnesium, manganese, and zinc were comparable to values obtained elsewhere. Lead and arsenic are undesir­able. Their occurence in the wines tested ranged from nil to 0.2 ppm, which is negligible. Iron and

copper are undesirable from the winemaker's point of view, since their presence in excess will cause a black colour or cloudiness, which render the wine unmarketable. The iron and copper content of the wines analyzed was low and all wines were clear and marketable.

Potassium content of wines analyzed was 236-1576 ppm. This is comparable with values obtained else­where, 450-1750 ppm, (Amerine and Cruess, 1960). Organoleptic evalu ation of wines and potassium content could be correlated. Better quality wines had a high potassium content. However, differences in quality of .the wines tested could be rather attri­buted to the origin of grapes than to the potassium content of wines.

ACKNOWLEDGEMENTS

We thank Mrs Stella Michaelidou, Senior Analyst at the State General Laboratory, and Mr. I. Papaconstantinou, Chief Laboratory Technician at the Agricultural Research Institute, for their con­tribution in the analyses.

REFERENCES

Amerine, M. A. 1960. LaboralOry procedures Jor enologists. Uni­ ./

versity of California, Davis

Amerine, M. A and W. V. Cruess 1960. The lechnology oj winemaking. The AV[ Publishing CDmpany. Westport, Connecticut.

A.OA.C 1975. OJficial methods oj analysis. Association of Offi­cial Agricultural Chemists. Washington, D.C.

Fornachon, J eM. 1953. Studies on the sherry Jlor. CSlRO, Australia.

Kourakou, S 1971. Internalional melhods oj analysis oj musts and wines. Wine Institute, Athens, Greece (mimeo, in Greek).

O. l v. 1978. Recueil des methodes internationales d' analyse des Vlns Office lnternational de la Vigne et du Yin, Paris

Vryonides, 'Ph 1976 Annual reporl on viticullUre and oenology. Department of Agriculture, Limassol.

Yokotsuka, K., and T. Kushida. 1983. General analysis of wines collected from various regions in Japan. Journal oj the Institute oj Enology and Viticulture, Yamanashi Univer­sity 18 43 - 50.

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