Major Inorganic Ions in Polish Beers

Beer is one of the most popular drinks consumed around the world. It is an complex beverage containing various classes of organic and inorganic compounds (Hornsey, 2003); some of them originate from the raw materials, while others develop through interactions and reactions during the brewing process, or can be the result of contact with the materials from which the equipment is made or packing materials (Alcazar et al., 2002). These components can affect the beverage in different ways. Very important issue in beer quality is water which may contains naturally occurring minerals and compounds, but also some anthropogenic contaminants (Morale-Rubio and de la Guardia, 2015). The overall concentrations of inorganic components generally range from 0.5 to 2 g/L (Olajire, 2020). The acid pH significantly affects the solubility of metals and non-metals in beer (Donaldini et al., 2008). The content of inorganic ions of greatest concern for the quality of beer are primarily fluoride, chloride, nitrate, phosphate, sulfate, sodium, calcium, magnesium, and potassium (De Keukeleire, 2000); they are mostly derived from malt, hops and brewing water. Due to its prevalence and volume of consumption, beer is an important source of Fdelivered into the human body (Styburski et al., 2017). If the chloride level exceeds 250 mg/L, then the sweetnes of the beer is enhanced, but yeast flocculation can be hindered. Sulfate found naturally in water imparts a sharp, dry edge to well hopped beers and is therefore kept to a minimum. Chlorides and sulfates are the ions of highest Abstract Reliable determination of various components of beers is still a challenge due to their complex matrices. Inorganic ions are very important components of beer; their content depends mainly on the quality of water and additional substances used in the brewing process. The major inorganic anions (F-, Cl-, NO2-, NO3-, PO43-, SO42-) and cations (Na+, K+, Mg2+ and Ca2+) were determined using isocratic ion chromatography with conductivity detection. Method optimization involved six ion-exchange columns; different eluent concentration and flow rates were tested. Optimized methodologies allowed for quick, selective and reliable analysis of these ions in 30 beers available on the Polish market. They were characterized by pH values from 3.19 to 4.64, and conductivity from 1632 to 2662 μS/cm. The content of inorganic anions ranged from 0.2 1.1 mg/L for F-; 8 235 mg/L for Cl-; NO2< LOD; 7 22 mg/L for NO3-; 44 188 mg/L for PO43-, and 10 95 mg/L for SO42-. In case of cations, it was 10 93 mg/L for Na+; 87 329 mg/L for K+; 54 329 mg/L for Mg2+, and 10-89 mg/L Ca2+. PCA Principal Component Analysis helped in establishing similarities between the analyzed samples.