I'm interested in how de minimis principles can apply in law and especially started thinking about it after reading that certain cities require food waste to be put in a plastic bag. For example, this source says that food waste "should be drained, wrapped and placed in a plastic bag before placing in [a] garbage cart." Likewise, this PDF for another city says that food waste should be "drained, wrapped and placed in [a] plastic bag."
What then is food waste? According to the EPA, even plate waste qualifies:
Food waste refers to food such as plate waste [emphasis mine] (i.e., food that has been served but not eaten), spoiled food, or peels and rinds considered inedible that is sent to feed animals, to be composted or anaerobically digested, or to be landfilled or combusted with energy recovery.
While I could be wrong, I have trouble thinking that all uneaten food on a plate must be put in a plastic bag before being thrown away. If such were the case, would even food crumbs qualify as food waste, or would this exemplify a de minimis exception?