The preliminary inquest found that overheating of an oven causing the smoke mid-air, the sources said, adding that the Directorate General of Civil Aviation's (DGCA) Kolkata office was conducting a further probe into the incident.
Terming the incident as "minor", Air India officials said there was no risk to the passengers or the aircraft at any point of time and their technical team was also conducting an inquiry as per the laid down norms.
"The cabin crew detected some smoke from an oven in the rear galley of the plane. They used fire extinguisher and immediately switched off the oven. At no point was the aircraft or the passengers at risk," an airline spokesperson said.
Air India would raise the issue would the US plane manufacturer Boeing which would have to rectify all problems, he said and added that the national carrier has a "zero tolerance policy" for any technical trouble.
Recently, a fire broke out inside an Ethiopian Airline's Dreamliner parked at London's Heathrow airport.