The invention relates to a method for producing effervescent granules, in which the reaction partners edible, organic acid components and alkaline effervescent components separating carbon dioxide are reacted with each other in a vacuum under the effect of gas in a container that can be evacuated. The container is evacuated to a first vacuum value within a vacuum range of 200-900 mbar, whereupon the pressure inside the container is increased to a second vacuum value as a result of the gases produced during the reaction. The steps are cyclically repeated while the reaction continues. A maximum number of cycles, a maximum reaction time, and optionally, a maximum load for the stirring apparatus are defined before the reaction begins, and the reaction is terminated after reaching the first of the maximums. In an alternative embodiment, the invention also relates to a method for improving the shelf life of effervescent granules by a treatment with carbon dioxide during and/or following the production of the effervescent granules, and effervescent particles treated in this manner.