The invention relates to a method for controlling microorganisms in a sugar-containing
aqueous process medium, especially in the sugar industry, using hop bitter acid
as active substance. The hop bitter acid is dissolved in an aqueous alkaline medium
and added to the process medium. The pH value of the added solution is higher than
the pH value of the process medium and the hop bitter acid passes from the dissociated
to the indissociated form in the process medium.
