Importance of tetrahydroiso α-acids to the microbiological stability of beer

Isabel Caballero, Montserrat Agut, Alicia Armentia, Carlos A. Blanco

    Producció científica: Article en revista indexadaArticleAvaluat per experts

    10 Cites (Scopus)


    While beer provides a very stable microbiological environment, a few niche microorganisms are capable of growth in malt, wort, and beer. The production of off-flavors and development of turbidity in the packaged product are due to the growth and metabolic activity of wild yeast, certain lactic acid bacteria (LAB) and anaerobic Gram-negative bacteria. Beer also contains bitter hop compounds, which are toxic to Gram-positive and Gram-negative bacteria, and contribute to preventing the spoilage of this beverage. In the boiling process, the hop α-acids (humulones) are isomerized into iso α-acids. These products are responsible for the bitter taste of beer, but they also play an essential role in enhancing foam stability. Antibacterial activity of iso a-acids and their hydrogenated derivates (rhoiso α-acids and tetrahydroiso α-acids) in MRS broth and beer have been evaluated against different LAB (Lactobacillus and Pediococcus) for the determination of their beer-stabilizing capabilities. Besides this, we have determined the minimum inhibitory concentration and the bacteriostatic effect of each compound against Pediococcus. We found that tetrahydroiso α-acids (added directly to beer during production processes) are the compounds that present the greatest antibacterial activity against the main agents implicated in beer spoilage.

    Idioma originalAnglès
    Pàgines (de-a)1160-1164
    Nombre de pàgines5
    RevistaJournal of AOAC International
    Estat de la publicacióPublicada - 2009


    Navegar pels temes de recerca de 'Importance of tetrahydroiso α-acids to the microbiological stability of beer'. Junts formen un fingerprint únic.

    Com citar-ho