Vegetables
Early researchBroccoli
Broccoli's key compound, sulforaphane, only forms when the vegetable is cut or chewed. One cooking choice changes how much survives.
Broccoli stir-fried with garlic
The enzyme that makes sulforaphane is destroyed by heat. Cooking it only lightly is what preserves the compound.
2 servings15 min
Ingredients
Method
Cut the broccoli into bite-sized florets and leave it for 40 minutes. In that window myrosinase converts glucosinolate into sulforaphane.
Slice the garlic and let it stand for ten minutes.
Heat the olive oil and fry the garlic over medium-low heat for 30 seconds. High heat scorches it and the allicin is gone.
Add the broccoli and stir-fry for two minutes.
Add the two tablespoons of water, cover, and let it steam for two minutes.
Uncover, cook off the moisture, and season with salt and pepper. Take it off the heat while the stems still have bite.
Cooking note
The 40-minute wait after cutting is the heart of this dish. Sulforaphane is not sitting ready inside broccoli: it forms when the tissue is broken and an enzyme converts the precursor. That enzyme is heat-sensitive, so heating immediately after cutting kills it before the conversion happens. It is the same reason steaming or a quick stir-fry beats boiling.
Ingredients used here
Vegetables
Moderate evidenceGarlic
The evidence for garlic points to a modest drop in blood pressure and cholesterol. The trick is to crush it and wait ten minutes before it hits the heat.