In the same year, the following variables were determined: density, alcohol, titratable acidity, volatile acidity, fixed acidity, pH, dry extract, reducing sugars, reduced dry extract, alcohol in weight/reduced dry extract, ashes, alkalinity of ashes, absorbance--420 nm (I 420) and 520 nm (I 520)--, color intensity (I 420 + I 520), hue (I 420/I 520), anthocyanins, tannins, total polyphenols index, volatile compounds--ethyl acetate, methanol, 1-propanol, 2-methyl-1-propanol, 2-methyl-1-butanol + 3-methyl-1-butanol and sum of higher alcohols.
However, they were by the year and there was an interaction between the rootstock and the year for methanol and 2-methyl-1-propanol (Table 3).
The straight-chain higher alcohols are considered to have the most significant sensorial impact (1-propanol, 2-methyl-1-propanol
(isobutyl alcohol), 2-methyl-1-butanol and 3-methyl-1-butanol (isoamyl alcohol).
Furthermore, 3-methylbutanal, 2-methyl-1-propanol
and ethyl acetate were in significantly higher concentrations in two of the yeasts.
The major volatile constituents (acetaldehyde, ethyl acetate, 2-methyl-1-propanol, higher alcohols (3-methyl- and 2-methyl-1-butanol), and acetoin) were determined by gas chromatography as previously described .
As regards the production of higher alcohols during fermentation, the amounts of 2-methyl-1-propanol (isobutyl alcohol) detected ranged from 13.26 mg/L (strain S47) to 49.70 mg/L (strain S52) and the summation of amyl alcohols ranged from 55.77 mg/L (strain S47) to 138.73 mg/L (strain S16).
Gopal, "Densities, ultrasonic speeds and excess properties of binary mixtures of methyl acrylate with 1-butanol, or 2-butanol, or 2-methyl-1-propanol, or 2-methyl-2-propanol at temperatures from 288.15 to 318.15 K," Journal of Molecular Liquids, vol.
Gopal, "Densities and volumetric properties of ethylacrylate + 1-butanol, or 2-butanol, or 2-methyl-1-propanol, or 2-methyl-2-propanol binary mixtures at temperatures from 288.15 to 318.15 K," Journal of Molecular Liquids, vol.
Identification and quantification was based on external calibration with standard solutions of acetaldehyde, 2-pentanone, 2-butanone, ethylacetate (Fluka, Buchs SG, Switzerland); ethanol (Arcus, Oslo, Norway); 2-methyl-1-propanol, 2-methyl-1-butanol, 2-methyl-1-butanal, 3-methyl-1-butanol, 2-methyl-1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanal, 3-methyl-1-butanol, 2-methyl-1-butanol, 2-methyl-1-propanal, diacetyl, 2-propanol, 1- butanol, 2-butanol, acetoin, iso-butylacetate, acetone, 2,3-pentanedione, ethylacetate, acetone, isobutyl acetate and ethyl butyrate (Merck KGaA, Darmstadt, Germany).
The alcohols identified in Obushera, in order of decreasing quantity, included: ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol and 2-methyl-1-butanol (Table 5).
Fusel oil usually includes n-propanol, 2-methyl-1-propanol, 2-methyl-1-butanol and 3-methyl-1-butanol in various concentrations.
1979) that a 5% concentration of Carbowax 20M gives the optimum resolution of methanol, ethanol, n-propanol, 2-methyl-1-propanol, 2-methyl-1-butanol and 3-methyl-1-butanol.