"Mena reaction" caramelization reaction furan "to create caramel sweet black coffee

Furan "creates caramel sweet fragrance

It wasn't until 1926, when two leading scientists, Tadeus Reichstein of Switzerland and Hermann Staudinger of Germany, led the study, that the mystery of coffee aroma was first uncovered. After 1950, the two men won the Nobel Prize in Medicine and the Nobel Prize in Chemistry for their outstanding contributions to science. The two masters can be called the ancestors of coffee chemistry.

Reichstein and Stoddinger's research report in 1926, for the first time revealed that furans (Furans), alkyl pyrazines (Alkylpyrazines), diketones (α-diketones) and sugar base mercaptan (Furfuryl mercaptan) and other 29 kinds of compounds are the main components of coffee aroma, of which furan compounds are the most important, coffee caramel, nuts, cream, almond and even fruit sweet aroma, are related to "furan" compounds.

In the difficult environment without the aid of "gas chromatography-mass spectrometry"(GC-MS), the two masters have found more than ten furans in coffee beans. Now scientists use GC-MS and other instruments, and coffee beans have identified more than 100 kinds of furan compounds, but not all of them are fascinating, some furan compounds smell very irritating.

Nans were thought to be the product of caramelization and the main source of medium baked caramel flavor. However, in recent years, scientists have found that the generation of coffee aroma does not rely entirely on caramelization, there are many furan compounds are reduced by fat, and even monosaccharides (reducing sugars) interact with amino acids, that is, the famous Mena reaction is the protagonist of generating richer furan compounds, so caramelization alone cannot explain the aroma process of coffee roasting, Mena reaction is the birth of coffee fragrance.

"Mena reaction" wins "caramelization"

"Mena reaction" refers to a series of degradation and polymerization reactions between monosaccharide carbohydrates (glucose, fructose, maltose, arabinose and lactose) and proteins (amino acids), and the color will also become dark. It was discovered by French scientist Mena (Louis CamilleMaillard) in 1912.

"Caramelization" only ends in the "oxidation" or "browning" reaction of sugar heating,"Mena reaction" has a wider range, all kinds of monosaccharides and amino acids react at different temperatures, will produce a more complex aroma, far more complex than caramelization, because caramel ingredients in the furnace temperature continues to increase, again degraded and polymerized with amino acids into pyrazine heterocyclic aromatic compounds, which is the source of chocolate flavor. However, caramelization is often mistaken as the main source of coffee sweet fermentation, ignoring the more important Menard reaction, which is more easily understood and rarely associated with the more complex name of Menard reaction.

Remember that the nutty, almond, creamy and chocolate aromas of roasting come from the Mena reaction, not caramelization. In other words, coffee that is caramelized without the Mena reaction has a monotonous sweet and bitter flavor, not a multi-flavor drink.

The nuts and many sweet aromas in SCAA's flavor wheel are classified as caramelization, which seems to simplify the sweet aroma formation somewhat, and the addition of the Menard reaction here can make the true results closer to the truth. Caramelization and Mena reaction under the "smell spectrum", can be classified into three flavor: nut rhyme, caramel rhyme, chocolate rhyme, such as the following table.

1. Nut rhyme: stone fruit and wheat tooth

Drupe: almond, peanut, walnut

Wheat: corn, rice, grain, toast

2. Caramel rhyme: candy and syrup flavor

Candies: toffee, hazelnut, licorice

Syrup: honey, maple syrup

Chocolate rhyme: dark chocolate and cream chocolate

Dark chocolate: bitter chocolate, Dutch chocolate

Cream chocolate: Swiss chocolate, almond chocolate