First-in-first-out is the rule most kitchens think they follow. For anything with an expiry date it is the wrong one, and the difference shows up in the bin.
FIFO says use the oldest delivery first. FEFO says use whatever expires soonest. On a shelf where everything arrived in order and expires in order, they agree, which is why the distinction feels academic.
Two rules that look identical until they aren't
Deliveries are not that tidy. A supplier ships stock they have held for four days alongside stock that came in this morning. A short-dated batch arrives after a long-dated one. The moment two batches of the same product carry different expiry dates, FIFO starts telling you to use the item that has longer to live and to leave the one that is about to turn.
You will not notice this on flour. You will notice it on dairy, fish, prepared components and anything with a three-day window, which is exactly the stock with the highest unit cost.
What tracking batches actually costs you
The objection is always the same: nobody has time to record a batch on receipt. Fair. But the cost is one scan at goods-in, and what it buys is a stock figure that knows not just how much you hold but how long it has. That is the difference between an alert that says "you have 12kg of salmon" and one that says "4kg of your salmon expires Thursday".
It also changes what a stock count means. Counting 12kg tells you the total is right. Counting 12kg across two batches with known dates tells you whether tomorrow's prep list should be built around using one of them up.
See where your own numbers disagree.
Thirty days of full access. Import your product list, run one count, and read the variance.