America's Test Kitchen LogoCook's Country LogoCook's Illustrated Logo

Blooming in Oil for Flavor

Blooming spices or herbs in fat before the liquid goes into the pot can extract far more flavor than by simply simmering these ingredients in water.

We’ve long advocated “blooming” spices and certain herbs in oil or fat before adding liquid to the pot, which our tastebuds tell us extracts more of their flavors. But we wondered if we could get at a more objective assessment of blooming’s impact.

EXPERIMENT: We steeped 50 grams of crushed red pepper flakes in 100 grams of canola oil and another batch in 100 grams of water, holding both liquids at a constant 200 degrees and steeping for 20 minutes. We then strained out the pepper flakes and sent the oil and water to a lab to test for capsaicin (the compound responsible for a chile pepper’s heat). We repeated the experiment with thyme and sent the oil and water samples to the lab to test for its main flavor compound, thymol.

RESULTS: The pepper-infused oil had a stronger flavor, with more than double the amount of heat-producing capsaicin, than the pepper-infused water. The results for thyme were even more dramatic: The herb-infused oil contained 10 times the amount of thymol as the herb-infused water.

EXPLANATION: The main flavor compounds in many spices and some herbs (including thyme, rosemary, lavender, sage, savory, and bay leaves) are largely fat-soluble. So by briefly heating spices (or herbs) in fat before the liquid goes into the pot, you can extract far more flavor than you could by simply simmering these ingredients in water.

FULLY BLOOMED:  Spices and herbs bloomed in oil can have 10 times more flavor.

This is a members' feature.