we offers Sindoor mix with jasmin Oil  to Hanumanji. There are basically two reason for this.

Sindoor :

   Saffron/Red is the colour of energy and vitality. Lord Hanuman is considered the saviour of people in Kaliyug. It is said that the Hanumanji can protect people from all kinds of troubles by infusing a person with self-confidence and power so he is generally depicted in saffron/ red colour.
   There is a very popular legend, where Hanumanji sees Devi Sita applying Sindoor for the Long and Happy life of Shri Raam. Since he loved Shri Raam also, he decided to cover his whole body with sindoor for Shri Raam’s Long Life. Seeing this act of Devotion, Lord Ram gave Hanumanji a boon that any body who offered Hanumanji Sindoor/Vermilion, would have a happy and long Life.

Oil : 

   Oil is basically offered to Shani Dev. It is believed, according to many legends, that Shani Dev sits below the Left Leg of Hanumanji. The Oil is pored on Mahavir’s Left leg, so that it might reach Shani Dev. Doing this is believed to lessen the harmful influence of Shani Dev.