To wash all this food down, you might drink milk bought right off the grocery shelf-without refrigeration. Using ultra-high temperature processing, engineers have developed a way to keep milk fresh longer, even at room temperature. Frozen desserts, like ice cream, have presented unique challenges to engineers. Formulation plays a role as well - when different flavors, fruits, and colors are added, the balance of the system is altered. Food provides a special challenge to engineers, because it is not as simple as other systems where physical and chemical properties are well defined and compositions known.
Most foods are complex mixtures made up of thousands of compounds.
Although food's chemical components can be broadly categorized as proteins, carbohydrates, fats, vitamins, minerals, flavors, and enzymes, this simplification does not truly reflect the variety of compounds within each class. What complicates matters more is that the compounds all interact with each other. And, processing food in the plant or cooking it at home changes the flavor, color, and nutritional characteristics. Food engineers are also involved in cutting-edge technologies, like genetic engineering, to produce crops more resistant to pests, or more durable for processing. One of the engineer's tasks is to translate a lab process to large-scale production.