A species of bacteria that is normally present in the human intestines. A common strain, Escherichia coli 0157:H7, produces high levels of toxins and, when consumed, can cause symptoms such as diarrhea, chills, headaches and high fever. In some cases, it can be deadly.

A protein that acts as a catalyst in organisms. In food, enzymes start the process of decomposition, changing the flavor, color and texture of fruits and vegetables. Enzyme action can be neutralized by following recommended food preservation methods.

An odorless, colorless gas that occurs naturally in nature. It is produced by and released from fruits during the ripening process. In turn, the ethylene gas acts as a ripening agent and, when exposed, speeds up the ripening of under-ripe fruits.

See venting.