Each book in this series follows a packet of energy along a journey. Each stage of the journey is described in a short chapter, and we learn what alternative paths the energy might have taken along the way. This book shows how the energy in crude oil is used to make a fast food snack. It explains how crude oil was formed, how it is obtained and how it is used in the food industry, the science behind cooking and the effects of heat on food, the processes of packaging and preserving food, and finally how fast food is prepared. The topics covered are illustrated with experiments, amazing facts and scientific discoveries.