Which is Neem Oil is the best depends on extraction of it. Neem seed is widely used in the extraction process instead of neem leaf as the oil content is found to be more in seeds than in the leaf. Primary process of extraction consists of grade wise separation of seeds. Grading of seeds is done according to the amount of oil content in the seeds and with sizes as well.
Pure Neem oil extraction methods, there are many methods that are applied to get oil.
Neem oil extraction is done by following methods
1. Mechanical press method- the neem fruits are collected in a container, and the kernels are separated to obtain the seeds, which are oven dried and then feed into the oil extracting machine in mechanical pressing method. The neem oil is obtained by pressing it mechanically and collected in a drum. Thus filtration is done to remove the various unwanted particles left in the extracted oil in order to obtain pure neem oil.
2. Steam pressure extraction method – the neem seeds after the drying are feed into the steam boiler. Due to it the seeds get swollen by steaming thus the oil in squeezing becomes easy and oil is extracted and filtered.
3. Solvent extraction method – solvents like petrol is mixed with the seeds after woven drying. The solvents help in extracting the neem oil out of the kernel up to certain percent. Added to that the neem seeds are pressed if needed. The resulting oil is stored in a silo where the pure neem oil is recovered from the crude one.
Other than these above mentioned methods, a latest extraction method called cold pressing is being adopted in many neem oil manufacturing industries. In the method Cold Press- it is seen that the purest form of neem oil is obtained along with the presence of active compounds (limonoids). It is the limonoids present in the Neem oil, that possess insecticidal properties. The main limonoid among all that it contains is Azadirachtin but also contains azadiradione, fraxinellone, nimbin,nimbidin,salannin, salannol, vilasinin etc. The oil extracted using cold press method seems to be lighter in color as well as odor when compared with other methods.
Note- Always use “Organic Certified Neem Oil for safe use” it comes in various Parts Per Million (ppm) best is 3000 PPM as a preventive measure.