TheDark beers contain an average amount of free iron of 121 ppb (parts per billion) compared to 92 ppb for blondesand 63 ppb for those without alcohol, according to an analysis of 40 types of beer from the five continents carried out by researchers from the University of Valladolid (UVA).
“Although these are very small quantities, the variations are clear, and could be the result of the production processes or the raw material used during manufacture,” Carlos Blanco, professor of the Technology Area, explains in statements to the SINC Agency. de los Alimentos at the UVA and co-author of the work.
The study, published in the journalJournal of the Science of Food and Agriculture, notes thatthe malt and hop extracts used specifically in the manufacture of stout may explain its higher iron levels. However, in the production of lager beer, a filtering is carried out with “diatomaceous earth” (sedimentary rock with microalgae used to clarify the drink), a porous material that traps the metal and reduces its concentrations. In the case of alcohol-free beers, vacuum evaporation processes are applied to remove the alcohol. This operation also favors the elimination of iron ions due to the drag exerted by volatile molecules.
To carry out the work, 17 brands of beer manufactured in Spain and 23 from other countries have been analyzed. Specifically, 28 blondes, six blacks and many others without alcohol. Those that contained the highest amount of iron were a Spanish black beer (165 ppb) and a Mexican beer (130 ppb), and those with the least, two without alcohol from Holland and Ireland (41 and 47 ppb respectively).
The determination of iron and other metals in beer is relevant not only because they are essential elements for the human body, but also because of their involvement in making the drink. Metal concentrations can determine its organoleptic characteristics, stability and quality.
