You can analyze components, but that doesn't give you a process to recreate in scale. Many aromas and stuff are remainders of some Enzym processing things or some chemical reaction where the initial ingredient is dissolved.
I myself spend some time in bread and a part of the taste of bread comes from my bacteria/yeast culture growing here at my place, feeding of stuff which is in the air at my place. If i go elsewhere that already changes to a small degree. If I vary temperature, humidity of air ... this has impact. On industrial scale the impacts are way more as they use processes to ensure the end product stays as much the same as possible independently from changes to ingredients (natural products change with each harvest ...) and where it is processed further (a Big Mac is, by McD, supposed to be as equal lgibally as possible) this is done by having Enzyms, chemicals and other comments doing their work.
