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WonderFood science fact

Fermentation is the work of yeasts and bacteria that feed on the sugars in food and turn them into acids, alcohol or gas. It gives us bread, yoghurt, cheese, wine and pickles, and it kept food safe to eat for thousands of years before refrigerators.

Fermentation

FoodScienceCultureBiology

The story behind the card

People fermented food long before they knew why it worked: residues in pottery jars from Jiahu in China show that a fermented drink of rice, honey and fruit was made there about 9,000 years ago. For centuries fermentation was thought to be a purely chemical process. In the 1850s the French chemist Louis Pasteur showed that it is the work of living microorganisms, and that different microbes produce different results, some pleasant and some that spoil food. That insight led to pasteurisation, gentle heating to kill unwanted microbes, first used on wine in the 1860s and later on milk.

Türkçe oku
Fermantasyon, yani mayalanma, mayaların ve bakterilerin yiyeceklerdeki şekerle beslenip onu asite, alkole ya da gaza dönüştürmesidir. Ekmek, yoğurt, peynir, şarap ve turşu bu sayede yapılır; buzdolabından binlerce yıl önce yiyecekler de böyle bozulmadan saklanırdı.

İnsanlar yiyecekleri, nasıl olduğunu bilmeden çok önce mayalıyordu: Çin'deki Jiahu'da bulunan çömleklerin içindeki kalıntılar, orada yaklaşık 9.000 yıl önce pirinç, bal ve meyveden mayalanmış bir içki yapıldığını gösteriyor. Fermantasyon yüzyıllar boyunca salt kimyasal bir olay sanıldı. 1850'lerde Fransız kimyager Louis Pasteur bunun canlı mikroorganizmaların işi olduğunu ve farklı mikropların farklı sonuçlar verdiğini gösterdi: Kimi yiyeceğe lezzet katıyor, kimi onu bozuyordu. Bu buluş, istenmeyen mikropları hafif ısıtmayla öldüren pastörizasyonun doğmasını sağladı. Yöntem önce 1860'larda şaraba, daha sonra süte uygulandı.

Sources and further reading

Background reading: Fermentation
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