Don’t forget to flick and knock on various fruits and vegetables. Randomize how many flicks/knocks per item, and throw in a few on produce items that normally don’t get that kind of test e.g. grapes or potatoes.
Wait, there are fruits/veggies that get this kind of treatment by typical customers? Please list a few.
Melons and squashes (inc. pumpkins).
I believe the idea is to allow you to roughly evaluate the density of the produce, to avoid e.g. mushy grainy watermelon or weird squashes that don’t have their expected hollowness.