chaptalization, common winemaking practice, named after its French promulgator Jean-Antoine chaptal, whereby the final alcoholic strength of a wine is increased by the addition of sugar to the grape juice or must, before and/or during fermentation, although if it is added before, the higher sugar level will make it harder for the yeast to multiply. Contrary to popular belief, Chaptal did not invent the process, which had been the subject of common experiment, not least by the innovative French chemist Pierre-Joseph Macquer.
