Evaluation of the Prevalence of Congeners from Distilled Spirits of Different Sources

Aim: With recent increase in health-related incidence arising from consumption of spirit beverages in Nigeria, there is need to investigate the prevalence of possible contaminants in spirits that may have toxicological effect on human when consumed. The purpose of this study was to determine the type and levels of congeners present in spirits obtained from fermentates of cassava, molasses and palm wine purchased from different locations.

Study Design: This study was made to fit a one way Analysis of Variance.

Place and Duration of Study: The research was carried out at laboratory of Department of Food Science and Technology, Federal University of Technology, Owerri and Project Development Agency (PRODA) Enugu and International Institute of Tropical Agriculture (IITA), Ibadan, Oyo State, Nigeria, between April 2017 and November 2018.

Methodology: Analysis of common congeners in spirits of cassava, molasses and palm wine fermentates obtained through distillation method was carried out using the Gas-Chromatography. Physicochemical properties of the spirits measured were specific gravity, pH and viscosity. The spirit distillates were analysed for concentrations of ethanol, higher alcohols and possible congeners such as esters, ethyl carbamate (EC) and ethyl acetate.

Results: The distillates yielded alcoholic content of 39.00 to 46.71%. Ethyl carbamate content of spirits from cassava recorded an average mean value of 13.44 µg/l which was not significantly different from (P > .05) spirits from molasses and palm wine, with an average mean values of 12.49 µg/l and 13.75 µg/l respectively. The most important higher alcohols of the spirit distillates responsible for aromatic characteristic of spirits were found to be 1-propanol (0.06-0.11%), isobutyl alcohol (0.02-0.09%) and isoamyl alcohol (0.12-0.76%). The type and location of raw materials did not significantly affect the concentrations of the available congeners found in the distilled spirits. Good fermentation employed in this research work significantly reduced the concentrations of the detected congeners.

Conclusion: Comparing the results with data from literature, it can be concluded that the concentrations of all investigated volatile compounds in the samples of spirits from cassava, palm wine and molasses are commonly acceptable. Federal regulatory agencies such as National Agency for Food Drug Administration and Control (NAFDAC), Standard Organization of Nigeria (SON) should be encouraged to carry out routine analysis on commonly produced and sold spirit beverages in order to prevent sale of contaminated drinks.