Generally, saving food that's been in a fire is not a good idea. Food exposed to fire can be compromised by three factors: the heat of the fire, smoke fumes, and chemicals used to fight fire. 

Heat from the Fire
Food in cans or jars may appear to be okay, but if they've been close to the HEAT of a fire, they may no longer be safe. Why? Heat from a fire can activate food spoilage bacteria. If the heat is extreme, the cans or jars themselves can split or rupture, rendering the food unsafe.

Fumes from a Fire
One of the most dangerous elements of a fire is sometimes not the fire itself, but TOXIC FUMES released from burning materials. Those fumes can kill; they can also contaminate food. Any type of food stored in permeable packaging — cardboard, plastic wrap, etc. — should be thrown away. Toxic fumes can permeate the packaging and contaminate the food. Discard any raw foods stored outside the refrigerator — such as potatoes or fruit — that could be contaminated by fumes. Surprisingly, food stored in refrigerators or freezers can also become contaminated by fumes. The refrigerator seal isn't airtight and fumes can get inside.
Discard food if exposed to smoke fumes from fire.

Chemicals in Fires
Chemicals used to fight fires contain toxic materials and can contaminate food and cookware. The chemicals cannot be washed off the food. Foods that are exposed to chemicals should be thrown away. This includes food stored at room temperature, such as fruits and vegetables, as well as foods stored in permeable containers like cardboard and screw-topped jars and bottles. Canned goods and cookware exposed to chemicals can be decontaminated. Wash in a strong detergent solution. Then dip in a bleach solution (1 tablespoon of unscented, liquid chlorine bleach per gallon of water) for 15 minutes.