Fat Extraction - Soxhlet's Fat Extraction Method Experiment
In the determination of the oil content of the sample, usually using organic solvents with a boiling point of less than 60 ℃ as a fat solvent (such as ether and boiling point of 30 ℃ to 60 ℃ of petroleum ether) extracted fat-soluble substances for the mixture of lipids, which contains fats, free fatty acids, phospholipids, esters, steroids, aromatic oils, certain pigments and organic acids, and so on, and therefore called crude fat.
Principle
The fat is extracted from the sample by leaching with a fat solvent, then the solvent is removed by evaporation, and the crude fat content of the sample is found by weighing the residue in the bottle or weighing the sample loss.
Operation method
Fat leaching - Soxhlet fat leaching method experiments
Principle
With fat solvent to extract fat from the sample, and then evaporate the solvent to remove, weigh the weight of the residue in the bottle or weigh the weight of the loss of the sample, you can find out the crude fat content of the sample. In the determination of the oil content of the sample, usually using organic solvents with a boiling point below 60 ℃ as a fat solvent (such as ether and boiling point of 30 ℃ to 60 ℃ of petroleum ether) extracted fat-soluble substances for the mixture of lipids, which contains fats, free fatty acids, phospholipids, esters, steroids, steroids, aromatic oils, certain pigments and organic acids, etc., and therefore called crude fat. Move I. Experimental materials, apparatus and reagents: For more product details, please visit Aladdin Scientific website.
1, Experimental materials: (1) plant samples to be tested; (2) filter paper cartridges.
2、Instruments: (1) Lang's fat leaching apparatus; (2) electrothermal constant temperature water bath; (3) analytical balance.
3、Reagents：(1) Ether.
Second, the operation steps:
1, the installation of the instrument:
Soxhlet fat dip extractor condenser tube and fat receiving bottle of frosted glass interface with a pencil number, wash and dry. Fat receiving bottle into the desiccator after cooling weigh the empty bottle quality, still put back into the desiccator standby. Mount the condenser securely on an electrically heated thermostatic water bath for heating using iron driving table clamps. Install rubber tubes at the inlet and outlet of the condenser respectively, the short tube leading to the serpentine tube inside the condenser is the inlet and the short tube leading to the outer layer is the outlet.
2, the sample weighing:
Take the filter paper cartridge (25 ф 70 mm) cut into 35 mm length, numbered with a pencil, symmetrically clamped on both sides of a paper clip, leaving a section of the iron ring for hooking. In the analytical balance weighing the weight of the empty filter paper tube, add 2 - 3 grams of samples prepared by 1 mm sieve, weighing its weight, and then to the filter paper tube stuffed with a small piece of cotton wool, to prevent the sample from dispersing, the filter paper tube has been added to the sample in a small beaker, and then placed in a 90 ℃ vacuum drying oven baked in 5-6 hours, remove the desiccator cooled for spare parts.
3, fat extraction:
Hang the filter paper tube in the condenser fixed on the hook at the lower end of the rod, and then add 70 ml of anhydrous ether to the fat bottle, set in the condenser below the mouth of the mill. Place the fat bottle with the condenser in place on an electrically heated water bath at a pre-set temperature (50-60°C). Loosen the stop clamp on the fixed rod, the filter paper cartridge immersed in ether, open the condensate valve, pay attention to the ether boiling situation, the requirements of the appropriate speed of reflux, not too fast, so as not to condense less than the ether in the upper part of the condenser to escape. Filter paper cartridge samples by hot boiling ether immersion 20 minutes, lift the filter paper cartridge operating lever to the highest position, condensed ether from the overflow pipe into, fill the filter paper cartridge, so that it drenched with filter paper cartridges on the upper wall of the cartridge, and then from the ether gradually recycling tube to recover the ether until the fat acceptance of the bottle of ether is completely evaporated until dry. Turn off the power and close the valve for condensate.
4、Drying of the fat bottle and recovery of ether from the filter paper cartridge:
Take off the fat bottle, wipe off the traces of hand touching and dust stained with silk cloth, put it into the 90 ℃ direct air drying oven to bake for 45-60 minutes and then take it out and put it into the desiccator, and then cool it down for half an hour and then weigh it. Immediately after the filter paper cartridge is detached from the hook, put it into an empty fat bottle, a fat bottle can be put into 4-8 at the same time, put on the cooler, open the cooling water, turn on the power of the water bath to recover the ether.