Fire Control.
The same 300 g of meat in the same wok can sear, stew in its own juice, or burn. Only the fire and the timing decide which.
Chinese cookbooks name four or five levels of fire. 旺火 or 武火 (fierce) — the flame at full, roaring up the sides of the wok — is for 爆 (explode-frying) and quick stir-fries, which must sear before juices run (XV.4). 中火 (medium) is for shallow-frying, most home stir-fries and reducing sauces. 文火 (gentle) is for braising (烧, 焖) and for frying aromatics without burning. 微火 (faint) is for long simmering (炖, 煨) — the surface barely trembling. A dish often uses several in turn: a 红烧 braise is browned over a fierce fire, simmered over a gentle one, then reduced over a strong one to glaze (收汁).
火候 is also timing: when to add the next ingredient, when to take the pan off. Restaurant wok burners deliver several times the power of a home burner, so food added to a ripping-hot wok keeps it far above 100 °C and sears and smokes — the 锅气 or "wok breath" of a restaurant stir-fry (XV.5). At home, the cure is smaller batches, a fully preheated pan and patience between batches (XV.3). The workshop puts a fire under a wok.
Below: the temperature of a 36 cm carbon-steel wok preheated 5 minutes at the fire you choose, then loaded with 250 g of cut meat (stove bench, lumped model), on a home gas burner or a restaurant wok burner; with the lowest temperature after the food goes in, browning, and what the dish does.
- Name the Chinese fire levels.
- Match each fire to a method.
- Explain wok hei and burner power.
- Use fire in stages within one dish.
Fierce, medium, gentle, faint — and when
In this model a home gas burner at full holds the loaded wok at about 218 °C at its lowest — enough for a good stir-fry in small batches — while at a gentle 35 % the food drops it to about 93 °C and stews in its juice. A restaurant burner at only 60 % keeps the wok near 318 °C, and at full it preheats to about 362 °C: so much heat that the cook must keep the food moving and turn the flame down between additions. That is why restaurant cooks constantly toss, add, lift and adjust — their fire is too strong to leave.
Using fire in stages, 红烧 style: sear over 旺火 to brown; add liquid and seasoning and bring to the boil; turn to 文火 and simmer covered until tender (XXVII.6); uncover and turn to 旺火 again to reduce the sauce to a glaze, stirring. For stir-fries: fully preheat, oil, add aromatics for a few seconds, then the main ingredient in a single layer, toss only when it has seared; add sauce at the end around the side of the wok, where it sizzles. Small batches at home do what a big burner does in a restaurant.
Stir-fry the same 250 g of sliced meat twice, once at full fire in a fully preheated wok and once at medium in a wok put on the fire just before. Compare colour and juice.
Terms
- 火候
- Fire and timing: the core Chinese cooking skill.
- 旺火 / 武火
- Fierce fire, for 爆 and stir-frying.
- 文火 / 微火
- Gentle and faint fire, for braising and simmering.
- 锅气
- "Wok breath": the seared, smoky taste of a very hot wok.
Sources
- A teaching value chosen for the course: the right order of magnitude and shape, not a measurement of a particular food.
- H. McGee, On Food and Cooking: The Science and Lore of the Kitchen, 2nd ed., Scribner, 2004.