Most people are familiar with commercially processed foods, such as boxed cereals and pastas, canned vegetables and soups, and frozen dinners and desserts. A large majority of the work that goes into getting these foods from raw ingredients to packaged products is controlled by food process engineering, which is the science behind creating and packaging commercially processed food items.
In general, food process engineering requires knowledge of the biological principles of food and environmental microbes, as well as mechanical engineering. This is because many different steps in the manufacturing of processed foods typically fall under the domain of food process engineering, from creating machines to mix the food to designing controls to ensure it does not become contaminated during processing to devising methods of packaging it.
One of the first steps typically controlled by food process engineering is the design of the machines that will be needed to manufacture the desired food item. This may include, for example, special mixers, ovens and freezers. To properly design such tools, food engineers must use their knowledge of various food characteristics — such as temperature sensitivity and cell wall integrity — to ensure the individual components that make up the processed food item will be kept in the ideal conditions throughout the manufacturing process.
Another key domain of food process engineering is microbial safety. When handled improperly, food is a often natural breeding ground for bacteria and other microbes found in the environment. Food process engineers use scientific knowledge of these microbes and the food being processed to create methods to help prevent harmful contamination. For example, milk or juice may contain microbes that are sensitive to heat, so pasteurization, or the heating of food items to a set temperature, is a type of food process engineering method that may be used to ensure the safety of these items. Similarly, fruits and vegetables that are going to be canned may have acid added to them to help retard the growth of acid-sensitive microbes.
Packaging also generally falls under the domain of food process engineering. This is because packaging is usually much more than a marketing tool. It often has to be specially designed to ensure the food stays fresh and safe until it can be consumed. For example, the principles of food process engineering guided the design and creation of the now familiar bagged lettuce packaging, which uses a special mix of gases to help keep the contents from browning or becoming limp. Essentially, from nearly all of the steps it takes to get from the farm to the shelf, the principles of food process engineering are used to help maintain the safety and quality of processed foods.
