Aldehydes in distillates.
Aldehydes (along with ketones) are part of what makes up carbonyl compounds. They are the most perceptible sensorially, providing much of the aromatic profile of distilled beverages. If you have the correct proportion of aldehydes in a drink, it will have a pleasant aroma; But if you have a very high amount of aldehydes, this can cause unpleasant rotting odors.
The generation of aldehydes is mainly during alcoholic fermentation, where the lack of nutrients or any element that reduces the viability or activity of the yeasts, generates an increase in the concentration of aldehydes. Not only can they be generated during fermentation, they can also be produced by oxidation-reduction reactions during the aging of distilled beverages. The presence of minerals in the barrels helps catalyze the oxidation of alcohols to produce aldehydes (1), (2).
Limits of the Mexican NOM of aldehyde content in distillates.
As in the case of methanol and furfural, the “Official Mexican Standard NOM-142-SSA1 / SCFI-2014 Alcoholic beverages. Sanitary specifications Sanitary and commercial labeling. (3)It is the one that establishes the permissible levels of aldehyde content in a distilled beverage. The maximum allowable limit is 40 mg of aldehydes per 100 ml of anhydrous alcohol. If large amounts of aldehydes are swallowed, this can lead to nasopharyngeal cancer (4).
There must be a control in the amounts of aldehydes in distilled beverages, in order to preserve pleasant aromas of the beverage without damaging the health of the consumer. Normally, the producers of distilled beverages refine their final products (whether they are matured or not) to avoid excess aromas or to remove some.
As a method of treating aldehyde levels, activated charcoal is one of the best options, thanks to its adsorptive capacity that can lower aldehyde levels in distilled beverages.
- Comparative study of rums and spirits aged in oak barrels and by the accelerated process. González, María D., Vázquez, Miguel A. and Redondo, Delda. Cuba: ICIDCA, 2006, Vol. XL (3).
- CIATEJ. Fermentative capacities and generation of volatiles of isolated yeast strains in different mezcal-producing states. Guadalajara: CIATEJ Institutional Repository, 2016.
- Official Mexican Standard NOM-142-SSA1 / SCFI-2014 Alcoholic beverages. Sanitary specifications Sanitary and commercial labeling. Health Secretary. sl: Official Gazette of the Federation, 2015.
- Agency for Toxic Substances and Disease Registry. Summaries of Public Health. Formaldehyde. [Online] 2019. https://www.atsdr.cdc.gov/es/phs/es_phs111.html