Wine Chemistry and Biochemistry

242 M. Luz Sanz and Isabel Mart ́ınez-Castro

Ta b l e 7. 4Polyalcohols in wine. Range in mg/L

Different wines

(De Smedt

et al. 1981)

Sweet white

(Liu and

Davis 1994)

Medium-dry

white (Liu and

Davis 1994)

Red (Liu and

Davis 1994)

Sherries

(Estrella

et al. 1986)

Erythritol 22–208 214 59 – 105–325
Threitol – 25 7 17–19 –
Ribitol – 23 3 106–140 –
Arabitol 0–266 18 8 83–108 17–42
Xylitol – 37 nd nd–15 22–149
Glucitol
(Sorbitol)

0–163 237 8 4–138 tr–134

Mannitol 31–420 116 53 194–493 tr–731
Galactitol nd–9 nd nd nd–9 –

nd: not detected

superior plants, especially mannitol. The alditols appearing in wine are considered

products of fermentation.

Inositols (cyclohexanehexaols, cyclitols) are cyclic polyalcohols with general

formula C 6 H 12 O 6 (as monosaccharides) but they are markedly stable to heat, acids

and alkalis. They are also difficult to ferment.

Myo-inositol (formerly calledmeso-inositol) is present, free or combined in the
tissues of all living species, excepting maybe a few bacteria.Scyllo-inositol has

been reported in grape juice and wine (De Smedt et al. 1981; Versini et al. 1984);

it has been proposed as genuinity control (Versini et al. 1984).Chiro-inositol has

been reported in citric juices (Sanz et al. 2004) and in several wines (Carlavilla

et al. 2006). Their (Table 7.5) structures appear in Fig. 7.9.

Quercitol is a deoxyinositol (1,3,4/2,5-cyclohexanepentol) which appears in cer-

tain Dicotyledons including all theQuercusgenus (Plouvier 1963). This compound

has been found in wines aged in contact with oak wood (barrels or chips) but not in

wines aged in bottles (Carlavilla et al. 2006).

Composition in polyalcohols of oenological tannis (See Table 7.5) from different

origins (oak, grape, quebracho, gall plant,etc.) has been recentlydetermined (Sanz

et al., 2008). These compounds appear to be useful markers to differentiate among

these botanical origins.

Ta b l e 7. 5Cyclitols in wine. Range in mg/L

Different wines

(De Smedt

et al. 1981)

White and

sherries in oak

(Carlavilla

et al. 2006)

Red aged in oak

(Carlavilla

et al. 2006)

Wines without oak

contact (Carlavilla

et al. 2006)

Chiro-inositol – 2–12 18–20 0–18
Scyllo-inositol 10–143 13–59 54–67 8–71
Myo-inositol 79–1044 348–478 306–412 199–427
Quercitol – 15–39 19–69 nd

nd: not detected