Mix-frying with vinegar

Stir-frying with vinegar. Vinegar is sour, bitter, and slightly warm, hence it can enter the liver channel, promote contraction, and relieve pain. For this reason, mix-frying with vinegar gives agents increased power to enter the blood and promote contraction, and to emolliate the liver and relieve pain. It can also improve flavor and smell. For example, it can remove the unpleasant odor of flying squirrel’s droppings (Trogopteri Faeces, 五灵脂 wǔ líng zhī). Vinegar contains acetic acid and therefore acts as a solvent: it can combine with free alkaloids to form soluble salts making active constituents easily extracted through decoction and increasing the speed with which the medicinal takes effect, as in the case of corydalis (Corydalis Rhizoma, 延胡索 yán hú suǒ). Agents most commonly vinegar mix-fried are liver-calming and qì-rectifying medicinals such as unripe tangerine peel (Citri Reticulatae Pericarpium Viride, 青皮 qīng pí), cyperus (Cyperi Rhizoma, 香附子 xiāng fù zǐ), bupleurum (Bupleuri Radix, 柴胡 chái hú), and corydalis (Corydalis Rhizoma, 延胡索 yán hú suǒ).

Method Herbs are usually treated by first mixing them with vinegar and leaving them to stand. They are then stir-fried over a low flame until they give off their aroma and turn slightly golden in color. They are then removed from the wok and left to cool ready for use. Animal products and shells are put in the wok and heated over a low flame. They are turned constantly while sprinkling the vinegar over them. Stir-frying continues until the materials completely absorb the vinegar, give off their own aroma, and turn slightly golden. In some cases, it continues until a slightly burnt smell is detected. One or more parts vinegar to five parts of materials represents the usual proportion, i.e., around 60g of vinegar for every 500g of materials.