The invention discloses a functional coffee liquid and a preparation method thereof, the functional coffee liquid comprises the following components in parts by weight: 26 parts of coffee liquid, 11 parts of Chinese herbal
medicine liquid, 0.8 part of cocoa
powder, 0.1 part of baking soda, 0.1 part of
xanthan gum and the balance of water, and the Chinese herbal
medicine raw materials comprise 4 parts of Chinese yam, 6 parts of liquorice, 6 parts of
ginseng, 7 parts of medlar and 8 parts of
astragalus membranaceus. The temperature of low-temperature baking is 140 DEG C, and the time is 30 minutes. Preferably, the coffee
powder and water are mixed according to the proportion of 1: 10, and cold extraction is performed at 4 DEG C for 20 hours. The acidity of the coffee is bright and prominent, the taste is mellow, the
flavor is fresh, harmful substances possibly caused by high temperature are prevented from being generated, and the deeper the baking degree is, the heavier the
charring feeling is, and the lighter the
flavor of the coffee beans is; the coffee extract is rich in fragrance, sour, sweet, bitter and salty in taste, free of heavy
bitter taste and scorched taste and mellow and clean in taste, the best
coffee flavor can be achieved, and the coffee liquid serving as the main
raw material has a long
shelf life under the normal-temperature placement condition.