Processed foods is mostly just a collective term for food with high amount of preservatives, food additives, heat treatment, cold treatment, grinding, emulsifyi

Processed foods is mostly just a collective term for food with high amount of preservatives, food additives, heat treatment, cold treatment, grinding, emulsifying, and other mechanical force being applied. Each step changes the food in ways that can have benefits but also drawbacks. Turn an apple into apple juice concentrate and then add water and what you have is not an apple. You got an apple-inspired surgery drink with almost none of the food properties of an apple. If people tried to reconstruct the apple using food additives, the result could even look like a physical apple and possible even fool people into thinking they are eating one, and yet it would not be an apple with the microbes, fibers, vitamin, minerals, skin and other parts for which makes an apple an apple. A 10-step recipy that you cook at home might include some aspects of an identical finished product that you could have bought at the store, but in general I suspect it has fewer of the destructive steps. Those that you do yourself might also be less effective, as one don't usually intend to have left overs that can remain in the fridge for several months with no change.