For this article I define "industrial food" as food that has been significantly modified, prepared, or packaged by an industrial process. This is a fuzzy definition because a lot of food is in fact produced industrially (such as by large intensive agriculture) and undergoes basic processing such as cleaning, milling, canning, or freezing, not to mention shipping. That food I discuss in Modern Agriculture and don't mean to be within the scope of this article. I view "industrial food" as the prepared complete dishes packaged for eating pretty much as is (out of the box or with reheating etc.), as well as the highly processed bulk ingredients used in commercial operations such as fast-food and many other restaurants.
Industrialization of food is a natural outcome of technological progress, as well as a main driver of it. Producing, harvesting, and storing food in greater quantity than one can use immediately allows greater food security and economic activity. However, the industrial nature of this process has grown to a level that food production is greatly distanced from its consumption, and it is more radically transformed. This impacts the food value itself as well as creates important consequences on ecosystems and social structures.
The first concern of course is the impact on nutrition. Industrial food does not provide the balanced nutrition food for several reasons. The production conditions aren't as favourable to the development of nutrients as non-industrial foods. While macronutrients such as sugars, fats, and proteins are present, micronutrients are not always at the levels they should be. Industrial food itself is often produced with minimal complexity in the inputs, such as one-dimensional fertilizers instead of compost, or carb-rich grain-heavy diets instead of more complex grass-based ones. Plants and animals produce more nutritious bodies when under a certain amount of stress, being forced to process more difficult to digest inputs, subjected to environmental variability, etc.
Beyond these factors in base nutrition is the way industrial foods are offered. While a human diet should be rich in fruits and vegetables, with modest amounts of proteins, fats, and carbs, industrial food reverses that. This is of course because humans evolved to preferrentialy seek foods that were more difficult to obtain in the natural environment. In order to sell more, industrial food producers exploit that preference. They have learned to produce proteins, fats, and carbs in vast quantity, and industrial food is overbalanced with those elements. Producers argue that they are simply selling what people want, and that people concerned about the nutrition could make other choices, which would in turn impact producers' choices. But these producers take advantage of natural urges that have applicability in a different environment, lack of education about how and why to resist this, and a gradual increase in the unhealthy factors so people get used to it as their daily diet without realizing how different it is from a few decades ago.
The gradual change in diet brought about by industrial food is an insidious factor in the modern first-world condition. Food historians describe how unhealthy quanitites of proteins, fats, and carbs became increasingly avaialable over the past several decades. Older people remember different diets in the past, but many have still gotten used to modern diets. Younger people don't even have the experience to compare. Even within a person's recent memory, the nutrition of food has gotten worse. This is made visible by climbing obesity rates. Even people who are considered to be not overweight today are notably heavier than people were a few decades ago, so our culture has gotten used to a different baseline. This is brought about in large part by the increasing availability and decreasing nutrition of industrial food.
Corporations mediate and largely cause this change. In the context of industrial food, the problem of corporations is their drive to increase production and sales regardless of the impact on surrounding systems. In the case of industrial food, some of the key systems that are allowed to suffer is the plants and animals that serve as inputs, and the humans that consume the outputs. Corporate food production abstracts inputs from what appears on the table, making it easy for people to ignore the reality of what goes into their food. This is the basis of many of the modern ethical concerns with food production, as well as a part of disconnection with the process of living that seems underlies many other modern problems.
Dependence on the corporations that do this is one of my other great concerns with industrial food. People who consume industrial food as a major part of their diet often lack the knowledge and interest in non-industrial foods. This means that, increasingly, they are dependent on the activities of corporations for a key part of staying alive. Those corporations patently don't have the best interests of their customers in mind, and use industrial food to manipulate their customers into acting against their own best interests nutritionally. These are the last entities we should be dependent on. Furthermore, in spite of the great power they have amassed, corporations are vulnerable. When a producer or distributor fails, the impacts on the population can be rapid and severe. I have heard that New York City could only survive for a day if transportation networks failed, and I believe the entire industrialized world isn't far behind that threshold. People who depend on industrial food don't have much of a "Plan B".
Packaging and transport
loss of cooking skill