Fat MeterHow to use
How does the Fat Meter work? Generally speaking, you need to read the instructions carefully before use, and different types of products may be different. Let’s look at the general method:
1. Fold the filter paper tube and put the folded filter paper tube into the filter paper tube holder.
2. Put a layer of absorbent cotton at the bottom of the filter paper cylinder and press it tightly. The compression thickness is about 2mm.
3. Weighing samples: For low-fat samples such as grain and feed, directly weigh about 2 grams of crushed samples, accurate to 0.0002 grams. Transfer the sample into the filter paper cylinder, cover with a layer of absorbent cotton, and press it to the filter paper cylinder mouth. Then put it into the aluminum cup, and keep the inside and outside of the aluminum cup clean.
4. Transfer the filter paper holder and the aluminum cup to the bracket together.
5. Pull up the handle, suck the filter paper holder onto the upper speed joint, and then pull down the handle. Load all the samples one by one.
6. Pour 50ml of ether or petroleum ether into each aluminum cup.
7. Clean the heating plate without any impurities.
8. Install the bracket into the instrument, depress the lever and lock it. Pay attention to check that the position of the aluminum cup cannot be shifted.
9. Keep the knob in the vertical position.
10. Pull up the handle and dip the filter paper holder into the aluminum cup. Start soaking.
11. Set the temperature.
12. Pull down the handle after soaking to start the extraction process. The extraction time refers to the table in the manual.
13. After the extraction time, turn the knob to the horizontal position for solvent recovery. Solvent is recovered in a glass bottle above the knob.
14. Turn off the power after the solvent is recovered.
Notes on the use of fat analyzer
1. Precautions
(1) Test sample It should be dried and ground finely. After quantitative weighing, it should be loaded into a filter paper tube. The filter paper tube containing the sample must be tight. It is best to add a layer of absorbent cotton on top of the sample.
(2) Samples containing a large amount of sugar and dextrin should be treated with cold water first, and then placed in the filter paper tube together with the filter paper after drying.
(3) If ether is used, it must be anhydrous, alcohol-free and peroxide-free ether. If it contains water, sugar and inorganic substances in the sample may be extracted, causing errors. lead to fat oxidation.
(4) Fully clean the solvent cup, and dry it in a 103±2℃ electric blast drying oven to constant weight (the difference between the two weighings before and after does not exceed 0.002g)
2. Note for measurement
(1) The liquid level of the extraction solvent added to the extraction chamber should be 1.5-2cm higher than the sample in the filter paper cylinder, otherwise it is difficult to penetrate the sample and the fat cannot be fully extracted , causing errors.
(2) The heating temperature should not be too high during extraction. Generally, the extraction solvent has just boiled, and the reflux speed should not be lower than 12 times/hour.
(3) After the extraction, when the solvent cup is placed in the oven to dry, the bottle mouth is inclined to one side and placed at 45°C, so that the volatile matter can easily form convection with the air, so that the drying is rapid.
(4) The drying time of the sample and ether extract in the oven should not be too long, because some very unsaturated fatty acids are easily oxidized into ether-insoluble substances during heating; moderately unsaturated Fatty acids are easily oxidized by heat and increase in weight. Without vacuum drying oven, it can be dried at 100-105℃ for 1.5-3 hours.
3. Pay attention after the test
(1) Clean the solvent cup in time and dry it.
(2) After the heating plate is cooled to room temperature, place the six solvent cups again and recover the solvent in the instrument.
(3) If the experimental environment is below zero in winter, the tap water in the condenser should be discharged to prevent freezing and cracking.
(4) Unplug the power cord and place the machine in a dry place.
