A common sensory deficiency of alcohol-free beers (AFB) is caused by the presence of worty aldehydes. The aim of this study was to develop and proof the concept of a selective adsorption step, facilitating the removal of aldehydes from AFB. Therefore, the performance of 21 adsorb
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A common sensory deficiency of alcohol-free beers (AFB) is caused by the presence of worty aldehydes. The aim of this study was to develop and proof the concept of a selective adsorption step, facilitating the removal of aldehydes from AFB. Therefore, the performance of 21 adsorbents (amine-functionalized polymers, hydrophobic resins and zeolites) was tested in wort. Among the studied adsorbents, hydrophobic ZSM-5 type zeolites (CBV28014, HiSiv3000 and ZSM-5 P-360) showed the best selectivity due to their 2-dimensional separation characteristics. Consequently, the obtained multicomponent isotherms in unhopped AFB revealed a linear adsorption behavior for all aldehydes, indicating non-competitive adsorption within the design space. The logarithms of the adsorption affinity constants were found to be linearly correlated to the compounds’ hydrophobicity and solubility. The concept was proven at pilot scale of 150 L, resulting in a reduction of aldehydes between 43.7–70.2 %, while conserving bitterness, pH and color of the AFB. Future work will focus on the sensory evaluation of the flavor-improved product.
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