Food scientists tend to use the terms food processing and food production interchangeably. At least I did until I started hanging out with farmers and agricultural specialists. I had to change my ways because, in the agricultural world, food production also means the growing and harvesting of crops.
At least food manufacturing as a separate meaning.
Not so fast! Usage throughout the internet suggest that all three terms are used interchangeably to refer to the conversion of ingredients to another state.
None of the three terms are listed in Merriam Webster, possibly because they are compound terms and you can derive their definition from each part. Except, of course, as some one who lives in this world of food, I want more precise definitions.
Food processing and manufacturing are defined in the Code of Federal Regulations as:
“Manufacturing/processing means making food from one or more ingredients, or synthesizing, preparing, treating, modifying or manipulating food, including food crops or ingredients. Examples of manufacturing/processing activities include: Baking, boiling, bottling, canning, cooking, cooling, cutting, distilling, drying/dehydrating raw agricultural commodities to create a distinct commodity (such as drying/dehydrating grapes to produce raisins), evaporating, eviscerating, extracting juice, formulating, freezing, grinding, homogenizing, irradiating, labeling, milling, mixing, packaging (including modified atmosphere packaging), pasteurizing, peeling, rendering, treating to manipulate ripening, trimming, washing, or waxing. For farms and farm mixed-type facilities, manufacturing/processing does not include activities that are part of harvesting, packing, or holding.1”
In my opinion, food processing is more general and can be used to describe even the simple tasks we might carry out at home, such as washing and peeling fruit. Food manufacturing only refers to the mass production of food in separate facilities.
Thus, food processing includes anything done to the food after harvest, from washing to making frozen dinners. Thus, unless you eat your apples straight from a tree, all food is processed in some way. There is an argument for saying that polishing that apple on your trouser leg is processing.
Food production is a synonym of food manufacturing and food processing unless you are referring to the agricultural production of food especially harvesting and post-harvesting of fresh produce. To add to this confusion, I found many references to food production as the process of transforming raw ingredients into prepared food products2.
In my mind, both food manufacturing and food production have the idea of large scale production. For example, washing and polishing thousands of apples an hour, rather than the one or two we might prepare at home.
I also tend to think that manufacturing is making apple sauce made in a kettle and then bottled rather than made in a pan on the stove. The changes that take place are the same, even if the scale is different. When apples are cooked, the cell walls, which are mostly made up of pectin, dissolve and breakdown. The sugars in the apple start to caramelize. These chemical changes happen in a small pan as well as in a large commercial kettle.
If we are cooking, either at home or at a restaurant, we are usually preparing food that will be eaten in the next day or so. This is what is different about commercial food manufacturing. If we are making 1000 gallon vats of apple sauce and then bottling it, we are making the food to last. The apple sauce has to have a shelf life of a few months or even years for it to be safe and flavorful. This is what makes food processing, food manufacturing, and food production different from cooking.
Thus, in my writing and thinking I try to use these terms separately. It ends up with me avoiding food production completely as it is too general and confusing depending on my audience. I use food manufacturing when I want to refer to food being made for commercial sale with an extended shelf life and I use food processing as an all encompassing term to refer to the changes that happens after the raw material leaves the farm. For example, washing apples and making apple sauce are food processing, on whatever scale we are doing it on.
Still this doesn’t mean I won’t mess up and sometimes use these terms interchangeably.
Why do we process or manufacture food?
Processing food has both positive (kills pathogens, extends shelf-life, makes interesting flavors, improves texture) and negative (destroys nutrients) effects. This is one of the strongest influences on my interest in food science as I am fascinated by the changes that take place during processing and storage. This started with my PhD research when I studied how vitamin C degrades when no air is present.
Given our definitions above, most foods we eat are processed and the science behind what happens is absolutely fascinating:
How does flour, water, and yeast become bread?
What about the changes to milk that bacteria and rennet cause to give all those different varieties of cheeses?
How did anyone work out that cassava (a common root starchy vegetable eaten in Africa) needed to be chopped up, soaked in water for 24 h and then cooked to remove the cyanide containing compounds. I imagine some Elder testing this on their villagers. “Oops, 15 h soaking isn’t enough”; “uhu, those pieces weren’t chopped up enough”.
If you have any questions about food processing, food manufacturing or food production, please let me know in the comments.