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WonderFood science fact

Toast, roasted coffee, fried onions and seared meat get their brown colour and rich smell from the Maillard reaction: heat makes sugars react with amino acids, the building blocks of proteins, creating hundreds of new flavour compounds.

American Chemical Society

ScienceFood

The story behind the card

The reaction is named after the French chemist Louis-Camille Maillard, who described it in 1912 while trying to recreate how living things build proteins. Its importance for cooking became clear later: in 1953 the American chemist John E. Hodge set out its main chemical steps, showing how heat, moisture and time decide which aroma compounds form. It works best on dry surfaces above about 140°C, which is why meat is patted dry before searing and why boiled food does not brown. It is different from caramelisation, in which sugar breaks down on its own; the Maillard reaction needs amino acids too, so each food browns with its own flavour.

Türkçe oku
Kızarmış ekmeğin, kavrulmuş kahvenin, kızarmış soğanın ve mühürlenmiş etin rengi ve iştah açan kokusu Maillard tepkimesinden gelir. Isı, şekerleri proteinlerin yapı taşı olan amino asitlerle tepkimeye sokar ve yüzlerce yeni tat ve koku bileşiği ortaya çıkar.

Tepkime adını, onu 1912'de tanımlayan Fransız kimyager Louis-Camille Maillard'dan alır. Maillard aslında canlıların proteinleri nasıl oluşturduğunu laboratuvarda yeniden yapmaya çalışıyordu. Buluşun mutfak için önemi sonradan anlaşıldı: 1953'te Amerikalı kimyager John E. Hodge tepkimenin başlıca kimyasal basamaklarını ortaya koydu ve hangi koku bileşiklerinin oluşacağını ısının, nemin ve sürenin belirlediğini gösterdi. Tepkime en iyi 140°C'nin üzerindeki kuru yüzeylerde ilerler. Et bu yüzden tavaya konmadan önce kurulanır, haşlanan yiyecekler de bu yüzden kızarmaz. Karamelleşmeyle aynı şey değildir: Karamelleşmede yalnızca şeker parçalanır, Maillard tepkimesi ise amino asit de ister. Bu yüzden her yiyecek kendine özgü bir tatla kızarır.

Sources and further reading

Background reading: Maillard reaction
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