On Onions and Maillard

Saturday, June 10, 2006

Question asked by a foodie friend:

In addition to varying degrees of sugars, onions vary in their levels of sulfur compunds, amino acids and water.

From McGee’s “On Food and Cooking”, p311:

Comparing the nutritional info for red onions vs different types of onions would be interesting. Unfortunately the usda database doesn’t have an entry for reds.

My limited understanding is that anthocyanins mainly contribute color to the red onion vs altering its flavor profile.

When sauteeing onions and pushing them beyond we’re bringing the Maillard reaction into play with the sugar-carbohydrate-amino acid compounds of an onion.

The accompanying diagram in the quoted text further shows how compounds beyond sugars lend themselves to the complex flavors of a Maillard reaction. The contributing sulfur compounds and amino acids produce more ‘ring’ structures, aka aromatics, than caramelization produces.

So, in addition to varying amounts of sugars, the various levels of sulfur molecules and differences in amounts of amino acids contribute to different flavors in different types of onions.

(I think we could also pull the concept of Terroir out from winemaking into the world of onion flavors, esp when talking about the low sulfur Sweet onions.)

ps usda info on
1. raw welsh onions (Allium fistulosum)
2. raw onion (Allium cepa)
3. sweet raw onion
4. yellow onion sauteed


posted June 11th, 2006 at 2:10 pm

What would we food techies do without McGee?

posted November 28th, 2014 at 11:13 pm

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