Prep par levels and shelf life: how much to prep, and the safety limits
Prep par = average daily usage × days of cover × (1 + safety buffer), and the days of cover can never be longer than the shelf life you have set for that item: 2.4 kg a day for 2 days with a 20% buffer is a par of 5.76 kg. While it waits, chilled prep must be kept at 8°C or below and hot-held food at 63°C or above (The Food Safety and Hygiene (England) Regulations 2013, Schedule 4).
Worked par
| Average daily usage (from sales or the last two weeks' prep sheets) | 2.4 kg |
| Days of cover until the next prep of this item | 2 |
| Shelf life you have set for it | 3 days |
| Safety buffer | 20% |
| Par = 2.4 × 2 × 1.20 | 5.76 kg |
| Already made and in date | 1.5 kg |
| Prep today = par − on hand | 4.26 kg |
Illustrative numbers; the method is the one the free par level calculator uses, and it warns you when the cover outlasts the shelf life.
The temperature limits (England)
| Rule | Limit | Source |
|---|---|---|
| Chilled holding of food that needs temperature control | 8°C or below | The Food Safety and Hygiene (England) Regulations 2013, Schedule 4, paragraph 2 |
| Hot holding of food that needs temperature control | 63°C or above | The Food Safety and Hygiene (England) Regulations 2013, Schedule 4, paragraph 6 |
| Hot food kept below 63°C for service or display (a legal defence) | Under 2 hours, and only once | The Food Safety and Hygiene (England) Regulations 2013, Schedule 4, paragraph 7(2) |
Scotland, Wales and Northern Ireland have their own regulations; check the rules for where you trade.
Setting shelf life for prep
There is no single legal table of shelf lives for kitchen prep. The day you write on the label comes from your own food safety management system (the FSA Safer Food, Better Business pack is the usual starting point for small kitchens) and can never run past the use-by of the ingredients that went into it. Once you have set it, it caps the par: if a sauce is good for 3 days, you cannot hold 4 days of it, however good the price on a bigger batch.
A prep par sheet that works
- List each prep item with its unit (kg, litres, portions, trays).
- Write the shelf life and the storage temperature next to it.
- Set the par from the formula above, capped by shelf life.
- Each morning, count what is on hand and in date, and prep the difference.
- Review pars weekly against what was sold and what was binned.
Questions chefs ask
What is a prep par level?
The amount of a prepped item you want ready at the start of service. You prep the gap between the par and what is already made and in date.
What temperature should a kitchen fridge be?
The legal limit in England for chilled food that needs temperature control is 8°C or below (Food Safety and Hygiene (England) Regulations 2013, Schedule 4).
How long can I keep prepped food?
As long as the shelf life your food safety system sets for it, and never beyond the use-by of its ingredients. Label every container with the item, the date made and the use-by.
Print a sheet with the free kitchen prep sheet template.
Sources
More chef questions: Food cost % by venue type · Menu price multiplier table · Pub food and drink GP mix · Portions per kg · Cooked vs raw weight · Kitchen energy cost per dish · Kitchen staff cost 2026/27 · Sunday roast cost per cover · UK wholesale staple prices
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