Malachite Green and Crystal Violet Detection Kit

Malachite Green and Crystal Violet Detection Kit

Malachite Green and Crystal Violet Detection Kit

There are over 50 types of edible pigments (coloring agents) allowed to be used in China, while there are over 3000 known non edible pigments. To detect and distinguish each pigment, a considerable amount of work is required. This method is only one of the non edible pigment screening methods, suitable for rapid screening of malachite green and some non edible pigments.

Sample Processing

1. Liquid foods such as soda, beverages, color wine, etc.: Take about 30mL of the sample and place it in a beaker, heat it to remove alcohol or carbon dioxide, and set the sample aside.

2. Solid food: Weigh about 10g of the crushed sample, place it in a beaker, add 30mL of water, shake well, filter, and set aside the filtrate. If the color on certain solid foods is insoluble in water, the "Sudan Red and other non food coloring rapid detection kit" should be used for detection.

Take 10mL of processed sample solution into a test tube, drop A reagent to adjust the pH to between 8-9, add a small amount of B test cotton, place the test tube in a water bath at 90 ℃ or above for 1 minute, stir the test cotton, remove it, rinse the test cotton with clean water, and the color on the test cotton will not fade and become non food coloring. For ease of judgment, take a small amount of cotton sample B, soak it in water, and compare and observe.

Malachite green detection

Take 10mL of suspicious blue or green liquid and place it in a test tube. Drop in reagent A to adjust the pH to between 10-11. Place the test tube in a water bath at 90 ℃ or above for 5 minutes. If the blue or green color fades away and becomes colorless, cool it with cold water. Then drop in reagent C to adjust the pH to between 2-3 and place it back in the water bath. After 5 minutes, the sample will return to its original color, indicating the presence of malachite green in the sample. At this point, cool the sample with cold water and adjust the pH to 7-8 (not higher than 9) using reagent A. Add a small amount of test cotton B and place the test tube in a water bath at 90 ℃ or above for 1 minute. Stir the test cotton and remove it. Rinse the test cotton with clean water. If the color on the test cotton does not fade, it can be further determined that the sample contains malachite green. If conditions permit, the sample can be sent to the laboratory for further confirmation.

5mg/L (malachite green).

【 Precautions 】

The reagent is corrosive, avoid contact with the skin. If it comes into contact with the skin, rinse immediately with clean water.

Storage conditions and expiration date

The reagent is stored at room temperature and has a shelf life of 1 year. PH test strips are effective for a long time.