Malt Whiskies Research Articles

DETERMINATION OF ETHYL CARBAMATE IN DISTILLED SPIRITS USING NITROGEN SPECIFIC AND MASS SPECTROMETRIC DETECTION

Gas chromatographic methods are described for the determination of naturally occurring ethyl carbamate in distilled spirits at levels as low as 5 ppb. Bottled products, such as whisky, gin and brandy, are extracted in the presence of n-propyl carbamate as internal standard and analysed by capillary column gas chromatography with either nitrogen specific or mass spectrometric detection. A shorter extraction procedure is satisfactory when the more sensitive and selective mass spectrometric detection is used. Direct sample injection without extraction may be used for higher alcoholic strength cask and new-make samples. Analysis of 181 blended Scotch whisky samples indicated ethyl carbamate concentrations ranging from 20 to 75 ppb. Concentrations in 48 malt whiskies ranged from 15–100 ppb. Ethyl carbamate was not detected in gin, vodka and rectified neutral alcohol. All concentrations in bottled product fell below the Canadian limit of 150 ppb in distilled spirits.

Changes in Volatile Sulfur Compounds of Whisky During Aging

ABSTRACTVolatile sulfur compounds of malt whiskies were analyzed using a gas chromatograph equipped with a flame photometric detector by direct injection and solvent extraction methods. Sulfur compounds identified by coupled gas chromatography‐mass spectrometry and by matching GC retention times were dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, 3‐(methylthio)propanal, 3‐(methylthio)propanol, 3‐(methylthio)propyl acetate, ethyl 3‐(methylthio)‐propanoate, dihydro‐2‐methyl‐3(2H)‐thiophenone, 2‐thiophene‐carboxyaldehyde, 5‐methyl‐2‐thiophenecarboxaldehyde, benzothiophene and benzothiazole. Quantitative changes in these volatile sulfur compounds were studied by analyzing 48 aged and unaged malt whiskies by these methods. Dimethyl sulfide, 3‐(methylthio)propyl acetate, dihydro‐2‐methyl‐3(2H)‐thiophenone and ethyl 3‐(methylthio)propanoate decreased rapidly during aging and disappeared within three years. Dimethyl disulfide decreased gradually during aging. Dimethyl disulfide proved to be formed during distillation by the action of copper.

Analytical Profile of Scotch Whiskies

Abstract In this study, 13 Scotch grain whiskies and 34 Scotch malt whiskies were characterized by both chemical and physical analyses. In addition, 34 blended Scotch whiskies secured in the United States were examined. Official AOAC methods were used to determine the components commonly used in characterizing distilled spirits. In addition, potassium, sodium, copper, zinc, iron, calcium, magnesium, and lead were determined by atomic absorption spectroscopy. Characteristics of the present samples are compared to American whiskies.