How to identify adulterated fish meal?

(1) Smell Odour High-quality fish meal smells pure and has no odor, while spoiled fish meal often has strange taste and odor.

(2) Look at fineness Fine fishmeal is finer, and the hand is pinched and softened. After putting it down, there is no impurity on the hand. Inferior fishmeal is thicker, oily or less oily.

(3) The taste of brackish salt is one of the criteria for judging the quality of fishmeal. High-quality fishmeal has a low salt content, and the salt taste is hardly noticeable when tasted. On the other hand, if the salt taste is heavy, it means that the quality of fishmeal is inferior.

(4) Heat identification method This method can test whether fish meal contains urea. Nitrogen in urea is ammonia nitrogen, accounting for about 46%, can be identified by burning method. The method is: Take 20 grams of fishmeal, place it on a clean piece of iron, and then heat it in an electric furnace or coal stove until the temperature of the iron piece reaches 70°C. If the fishmeal emits a slight pungent ammonia smell, it can be determined. For urea fish meal.

(5) Washing identification method Some fishmeal is mixed with other animal and vegetable protein and sand and can be identified by water washing. Choose a glass with a high degree of transparency and put it into about 40 grams of fishmeal. Add more than half of the water. Stir quickly with a chopstick or wooden stick in one direction. Stop stirring and quickly pick up the cup against the sun or light. There is sand on the bottom to prove that the fish meal is mixed with sand. Then wash the fishmeal with Taomi several times, until the fishmeal is almost full, use a straw to aspirate the deposits on the bottom of the cup and observe it carefully on a flat glass. If there are tiny red sauce pieces, prove it. Incorporates plant protein; if there are tiny red meat particles or filaments inside, it proves to be mixed with animal protein.