Food fermentation is when food breaks down and converts sugar to either lactic acid or alcohol. It is a bacteria, but a healthy one like penicillin, and aids in the preservation of food. Alcohol, pickles, yoghurt and sourdough are fermented foods. Eating more fermented foods will boost your immune system as it is naturally probiotic. The health benefits of fermentation are known all over the world: the Japanese macrobiotic diet encourages the consumption of pickles because they aid digestion, while in Eastern Europe, cabbage is fermented whole in barrels. You can ferment most foods and salt is the key ingredient that prevents them from rotting. Real sauerkraut takes time – it should be fermented slowly. The proportion of salt is 3 tablespoons for every 2 kg of cabbage.