> [ultra] processed
This whole terminology just brings about brain damaged discourse as seen in this same thread. Just you wait for someone to say "itS jUsT LiKE caLLiNg wAtER dIHydrOgEN mONoXide".
I much prefer the following:
1. Food providers basically do all this crap to reduce costs. That's it that's the incentive. For _various_ reasons, a good, local food supply chain has become expensive. If we go debugging the causes of that we will find that the solution is outside the purview of a nutrition department. Let's not do that.
2. Instead, we try to limit menus that tend towards being cheap (like school food in this context) to contain dishes that are cheap by default. Food that's cheap by default, pre-cost-optimisation, is most often simple food. Small number of ingredients, very simple cooking process, minimal frying, etc,. Simple enough that they can just make it right there from start to finish, or somewhere nearby, for low cost, with minimal supply volatility.
Using my hollywood-inspired knowledge of the american school menu, but practical experience with handling food at schools in India, I'd suggest s/cereal/oats+fruits, s/mac-n-cheese/simpler pasta dish-say pesto or shredded chicken pasta, s/choco milk/just milk, s/chicken nuggets/pulled chicken sandwich with simple veggies. Can add some stew/soup in there as well. Beans too if needed. All with simple spice combinations.
These can be easily made fresh on-site or at a satellite kitchen serving 10-15 schools. Beyond 30-40 is when even this gets dicey.
Eggs I suppose schools won't be (probably aren't right now) allowed to break it and cook it on-site due to salmonella risk, which is why they all use pasteurised pre-made crap. So I've omitted it. It's also weird for lunch, I assume. I've left out cheese too due to the tendency for folks to shift to imitation cheese, as it's most common cheese even in usual grocery shops. Oil is also minimal - you basically are only using a drizzle of it for trapping flavour above. No frying is done. Bread is pretty much the only processed product left there, you can probably mandate whole wheat % for those, but still, overall it will be a big improvement.
Instead of playing a cat and mouse game where you make regulations, and you get back the same effect just through a route skirting those regulations, a practical solution similar to the one above, which removes the incentives to skirt, might be in order.
That said, I don't think school food has much to do with child obesity crises. What they eat outside school far outweighs school food in quantity. It's an easy political win though since it's the only part of kids diet that govt controls, which is why they harp on about it.