According to Alex Lewin, author of Real Food Fermentation and Kombucha, Kefir, and Beyond, fermenting is the opposite: ‘It’s unlike canning—with canning you kill all of the microbes and seal it hermetically. With fermentation you invite the microbes you want and don’t let in the ones you don’t. Fermentation is diplomacy and canning is a massacre. Canning is a high-tech food technology.’