The SCIENCE of COOKING - Dr.Stuart Farrimond
TASTE & FLAVOUR
Why does cooked food taste so good?
Taste is a surprisingly complex process.
In 1912, French medical researcher Louis-Camille Maillard made a discovery that would leave a lasting impact on cooking science. He analyzed how the building-blocks of protein (amino acid) and sugars react together, and uncovered a complex family of reactions that begin to take place when protein-containing foods, such as meats, nuts, cereals. and many vegetables, reach around 140ﾟC (284ﾟF).
We now call these molecular changes the “Maillard reaction”, and they help us to make sense of many ways in which food browns and takes on flavour as it cooks. Seared steak, crispy fish skin, the aromatic crust on bread, and even the aroma of toasted nuts and spices are all thanks to this reaction. The interplay of the two components creates enticing aromas unique to each food. Understanding the Maillard reaction helps the cook in many ways: adding fructose-rich honey to a marinade fuels the reaction; pouring cream into simmering sugar provides milk proteins and sugars for butterscotch and caramel flavours; and brushing pastry with egg provides extra protein for the crust to brown.
THE MAILLARD REACTION
Amino acid - the building-blocks of protein - clash with nearby sugar molecules (even meats contain traces of sugar) to fuse into new substances.
Fused molecules fling themselves apart and crash into others to combine, separate, and reform in countless ways. Hundreds of new substances are born, some brown in colour and many carrying aromas. As the temperature climbs, more changes occur. The exact flavours and aromas generated by browning depend on a food's unique combination of protein typer and sugars.
UP To 140ﾟC (BEFORE THE MAILLARD REACTION)
The Start of cooking
The temperature needs to reach around 140ﾟC(284ﾟF) before sugar molecules and amid acids have enough energy to react together. While the outer layers of the food are damp, food will not warm above the boiling point of water (100ﾟC/212ﾟF), so surface moisture must be driven of f by dry heat for this to happen. The exact flavours and aromas generated by browning depend on a food's unique combination of protein types and sugars.
140 - 160+ﾟC (DURING THE MAILLARD REACTION)
140ﾟC(284ﾟF)
At around 140ﾟC(284ﾟF), protein-containing foods start to turn brown in the Maillard reaction. This is also called the “browning reaction”, but colour is just part of the story. At this heat, protein and sugars clash and fuse, creating hundreds of new flavour and aroma substances.
150ﾟC(302ﾟF)
Maillard reactions intensify as the temperature rises. As food reaches 150ﾟC(302ﾟF), it generates new flavour molecules twice as quickly as it did at 140ﾟC(284ﾟF), adding more complex flavours and aromas.
160ﾟC(320ﾟF)
As the temperature increases, molecular changes continue and more enticing new flavours and aromas are created - the flavour enhancement peaks at this point. There are now cascades of malty, nutty, meaty, and caramel-like flavours.
180ﾟ〉(After THE MAILLARD REACTION)
180ﾟC(356ﾟF)
When food reaches 180ﾟC(356ﾟF), another
reaction called pyrolysis, or burning, begins and food starts to char, destroying aromas and leaving acrid, bitter flavours. Carbohydrates, proteins- and then fats, break down, producing some potentially harmful substances. Watch food closely and remove from the heat before food begins to blacken.
