Cooking with Oil
Many of the recipes in this book call for deep-frying foods in large amounts, from two to eight cups (500 ml to two liters), of vegetable oil. When foods are deep-fried at the proper temperature, they absorb very little oil, but, it can be difficult to judge whether oil is at the right temperature.
Although many Chinese recipes call for oil to be heated "to the smoking point" when deep-frying, it should be pointed out that the cooking oils used in China are often less highly refined than those used in the West. The presence or absence of impurities changes the appearance of oil as it heats.
We therefore suggest using thermometers to gauge how hot oil is.
Warm oil is about n this temperature range, no bubbles will appear around a small piece of vegetable leaf like a piece of scallion green or spinach, or a slice of ginger, that has been tossed into the oil.
Moderately hot oil is about . In this temperature range, small bubbles will sizzle around a piece of ginger, or scallion tossed into the oil.
Very hot oil is about , a one-inch cube of day-old bread will turn brown in one minute when dropped into the oil.
Boiling oil is above . A heavy haze appears and the oil bubbles vigorously.
Most Chinese recipes call for oil to be heated to the hot or very hot stage. Lower temperatures are used in methods like sliding through the oil, while extremely hot oil is used to crisp and brown coated foods that have already been fried at a lower temperature.