As it spreads across a country, a medical food can be adapted with new ingredients, more common in each region. This modification can also be done through the different types of storage of this food that each region presents that ends up modifying the flavor and appearance of that food. Finally, the modification of the ethnic food can be modified through its denomination, adopting local and more common names for each region.
An example of this can be seen in Brazil, where an ethnic food is called "munguzá" in the north of the country and is called "canjica" in the south of the country. The ingredients of this food also change according to the availability of the region. Northern Brazil has a high availability of corn, which is the main ingredient of this food, so this food is made with fresh corn recently harvested. The south of the country does not have this availability and ends up making this food with processed corn, which was harvested a long time ago and has undergone an industrial conservation process. This completely changes the taste of the food.
Based on the information I was able to find I would say "Natural gases".
This is due to the reason it is burned to create heat for buildings which are used for several things we do daily such as cooking, heating, and electricity.
