Why was bacon grease collected by the government during World War 2?

There was much sacrifice during the war. Food, gasoline, and nylons were among some of the items that were rationed. Sugar was the first item to be rationed; canned goods were needed for armaments and cans for soldiers; nylon and silk stockings were used in the manufacture of parachutes and powder bags for Naval guns; and bacon grease was used in the manufacture of ammunition. During World War II, the Allied forces discovered that it carried unparalleled incendiary properties, and successfully deployed it to undermine the German V2 rocket program.