Magnetic stirrers are commonly used in laboratories to stir samples and are widely used. One such application is stirring milk powder for the milk powder impurity determination process. Milk powder manufacturers and food testing departments often need to test the impurity of milk powder to ensure the quality of milk powder. However, the traditional method is to use manual stirring, but this is time-consuming and laborious. Probably, the average person can only detect 5-7 batches per day, and the efficiency is very low. With the advancement of technology, magnetic stirrers gradually replace manual stirring to stir milk powder, which greatly improves the efficiency.
Advantages of Magnetic Stirrer over Manual Stirring
1. The magnetic stirrer stirs more evenly and is more conducive to detection;
2. Save time and labor, the efficiency is more than 5 times higher than that of manual mixing, which is at least 3 times higher than the entire detection efficiency;
3. Save the container and save the cost. Manual stirring will inevitably break the beaker occasionally and lose milk powder;
4. When stirring, the staff can do other work similar to weighing at the same time to improve work efficiency.
How to stir milk powder with a magnetic stirrer
First, take a 1000mL beaker, add 400ml of 60°C distilled water, put a magnetic bar, and place the beaker on a magnetic stirrer;
Second, start the magnetic stirrer, and adjust the speed of the speed knob to gradually increase from slow to maximum speed;
Third, slowly add the weighed milk powder to be tested into the beaker;
Fourth, after the milk powder is stirred evenly, add 300mL of distilled water at 60 degrees Celsius.
The whole process only takes about 1 minute, and the milk powder can be completely dissolved and stirred evenly, and then the milk powder can be filtered and detected for impurities.
Matters needing attention in the process of stirring milk powder with a magnetic stirrer
1. After the magnetic stirrer is started, the speed control knob should gradually increase from slow to fast, and it cannot be adjusted to the maximum speed as soon as it is started, so as to prevent the magnetic rod from bouncing;
2. When adding milk powder, firstly, add it slowly at the height of the rotating water, and do not pour it all at once; secondly, do not add it in the center of the vortex of the rotating water, so as to prevent the magnetic bar from being impacted by the milk powder and causing a position shift Or dipped in powdered milk without turning.
3. Keep an appropriate amount of water, too much may cause the milk powder to splash out during stirring and affect the test results.
At present, the detection of impurities in milk powder basically uses a magnetic stirrer, which is fast, convenient and efficient.
This article refers to Dong Xicai's "Magnetic Stirrer for Measuring Milk Powder Impurity"
