https://makersplace.com/mitrai/blue-flame-1-of-1-46572/
Svāhā is a minor goddess and consort to Agni - the fire god. At the end of chanting , her name has to be taken - without that all the offerings made to the celestial beings are rejected. That is what wikipedia says .. I heard a story when I was young.. the blue flame that dances among the yellow and orange - that is Svāhā...