Every puja is followed by aarti which is performed by lighting the lamp or jyot. The flame of the lamp, jyoti has two significant qualities. First, it banish darkness and the other is it is always upward. The upward movement of the Jyoti signifies the path of wisdom and the path of divinity. Flame also signifies the power of all the beings so it is also considered as form of Maa Durga. Without fire element or Shakti no one can survive in this universe.
It is believed that in the houses where daily jyoti is lighted there can never be darkness or evil forces.
For this various type of oils are being used by devotees. In north India people use desi ghee preferably cow ghee, for shani puja mustard oil is being used and so on. Some experts believe that the mixture of couple of oils removes all the vastu doshas and bring prosperity in the house where such jyot is lightened every day.
As per old scriptures the jyoti lightened in Pancha Deepa Oil brings best results of any puja. The pancha deepa oil is a mixture of pure ginger oil, castor oil, Eluppai oil, Poongan Oil and Cow ghee. Using this oil for lighting the lamp would fill the place with extra ordinary vibrations, giving fulfillment in the prayers.