Parent said "understand food chemistry", which I understand not to be the chemistry of food as it relates to molecules and chemical reaction chains, but rather something more basic: this thing can soak too much oil, this burns quickly even in moderate fire, this food gets soggy if you put in this before that, and such things.
"Food chemistry" generally means the chemical reactions in food -- the actions of acids and bases, fats, gluten, starch and so on.
My mother studied food chemistry at college, so childhood baking generally included 20 seconds of explanation on why something I was about to do would make a mess. ("If you don't do X, the protein in won't coagulate and it will all fall apart.")
This mostly applied to baking, cooking eggs, or making a roux. The rest doesn't really matter.
Parent said "understand food chemistry", which I understand not to be the chemistry of food as it relates to molecules and chemical reaction chains, but rather something more basic: this thing can soak too much oil, this burns quickly even in moderate fire, this food gets soggy if you put in this before that, and such things.