Kitchen Stock Control: How to Reduce Shrinkage

Shrinkage is a gap you can measure

Shrinkage is the difference between what your sales say you should have used and what you actually used. Spoilage, over-portioning, waste, theft and delivery errors all land in that gap, and the number tells you how big it is before you know the cause.

The formula

Shrinkage % = (theoretical usage − actual usage) ÷ theoretical usage

Technically the gap is actual usage above theoretical, so many people calculate it as (actual − theoretical) ÷ theoretical and read a positive number as loss. Choose one convention and keep to it.

Theoretical usage comes from sales × recipe card (for example, 120 portions sold × 180 g = 21.6 kg).
Actual usage = opening stock + purchases − closing stock.

A worked example (illustrative)

Item: chicken breast. Opening stock 8 kg, purchases 30 kg, closing stock 6 kg. Actual usage = 8 + 30 − 6 = 32 kg. Sales for the week imply 150 portions × 0.180 kg = 27 kg of theoretical usage.

Gap = 32 − 27 = 5 kg, which is 5 ÷ 27 = 18.5% above theory. At €9.00 per kg that is 5 × 9.00 = €45 for the week, about €2,340 a year, from one item.

Part of that gap may be legitimate: trim, cooking loss, staff meals. If the recipe card already counts trim, the gap is real loss. If it does not, the card is out of date.

A weekly routine

Count weekly the ten items with the biggest cost. Not everything; the expensive items drive most of the loss.
Compare actual and theoretical. Investigate large gaps first.
Check the usual causes. Portion sizes, trim yield, wrong deliveries, unrecorded staff meals, spoilage, sales entered under the wrong item.
Standardise portions and receiving checks. Weigh deliveries against the invoice, and use scoops and scales for portions.

What is a normal level?

Do not borrow a "normal" level from elsewhere. Normal depends on your menu: a kitchen that butchers its own fish will have more trim than one that buys fillets. Track your own baseline for a month, then set a target you can improve against.

When the gap stays large

Look at one item and one cause at a time. Change one thing, such as weighing every portion of one dish for a week, and see if the gap moves. Small controlled changes show you what works.

Takeaway

Measure the gap between what you should have used and what you did use, weekly, on your most expensive items. Start with a baseline and improve from there.