A restaurant owner buys 15 kg of whole salmon at €12/kg, processes it into individual portions, and discovers their actual cost per serving is 40% higher than expected. Bulk purchasing saves money upfront, but processing in small batches creates hidden costs that many operators miss. Calculate wrong, and you'll underprice every dish.
Why batch calculation matters
Bulk purchases create multiple cost layers beyond the sticker price. You've got processing time, cutting losses, storage expenses, and labor that all stack up. Skip these calculations and you're essentially giving away profit on every plate—a mistake that costs the average restaurant EUR 200-400 per month in underpriced dishes.
💡 Example:
You buy 10 kg of beef for €120 (€12/kg). After processing you get:
- 8 kg usable meat (20% cutting loss)
- 2 hours labor at €20/hour = €40
- Packaging and storage: €8
Actual cost price: (€120 + €40 + €8) / 8 kg = €21/kg
The complete cost breakdown
True batch costing means accounting for every euro spent. Here's your formula:
Cost price per kg = (Purchase price + Processing costs + Storage costs) / Usable weight
- Purchase price: What you pay your supplier
- Processing costs: Labor for cutting, marinating, portioning
- Storage costs: Packaging, labels, freezer space
- Usable weight: What remains after cutting loss
⚠️ Watch out:
Processing time isn't free labor. Two hours of prep work at €20/hour adds €40 to your costs—ignore this and you're losing money before the first order goes out.
Calculate cutting loss correctly
Cutting loss inflates your real cost per usable kilo. With 20% waste, you're paying 25% more than the purchase price suggests.
Actual price = Purchase price / (100% - Cutting loss%)
💡 Cutting loss example:
Whole salmon €18/kg, 45% cutting loss:
- Yield: 55% (100% - 45%)
- Actual fillet price: €18 / 0.55 = €32.73/kg
So your fillet costs almost double the whole fish!
Estimate processing costs
Time your prep work and multiply by your kitchen's hourly rate. Budget €18-25 per hour for staff wages plus employer contributions.
- Cutting and portioning: 15-30 minutes per kg
- Marinating and seasoning: 5-10 minutes per kg
- Packaging and labeling: 5-10 minutes per kg
Include storage costs
Small expenses compound quickly across multiple batches:
- Packaging materials: Bags, containers, labels
- Freezer space: Share of your energy costs
- Shelf life: Risk of spoilage during storage
💡 Practical example:
Processing 10 kg chicken thighs into portioned batches:
- Purchase: €35 (€3.50/kg)
- 1.5 hours cutting: €30
- Packaging: €12
- Usable: 8.5 kg (15% loss)
Cost price: (€35 + €30 + €12) / 8.5 kg = €9.06/kg
Digital tracking for overview
Food cost management systems help you log purchase prices, processing time, and final yields per batch. Over time, you'll build accurate cost data for each supplier and seasonal variation.
How do you calculate the cost price per batch? (step by step)
Record all purchase costs
Note the total purchase price of your bulk purchase. Also add transport costs and any surcharges. This is your basis for the calculation.
Measure cutting loss exactly
Weigh the product before and after processing. Calculate the loss percentage and usable weight. This determines your actual yield per kilo.
Calculate processing and storage costs
Add up the time you spend cutting, portioning and packaging. Multiply by your hourly rate and add storage costs.
Divide total costs by usable weight
Divide all costs (purchase + processing + storage) by the usable weight. This gives you the actual cost price per kilo for your recipe calculation.
✨ Pro tip
Track your processing times for the same 3 bulk items over 30 days—you'll discover your average prep speed and can price labor costs within €2 per batch accuracy.
Calculate this yourself?
In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.
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Frequently asked questions
Do I always need to include processing time in the cost price?
Absolutely—labor isn't free, even if it's your own time. Two hours of prep work costs €40 in wages, and skipping this calculation means losing money on every dish you serve.
How do I calculate cutting loss if I use different parts?
Weigh each usable component separately and track what actually makes it onto plates. Bones for stock have value, but pure waste doesn't—only count parts that generate revenue in your yield calculations.
What if my cutting loss differs per supplier?
Track average yields by supplier since quality affects your bottom line. A supplier with 10% less waste might justify paying 5% more upfront. Document these differences for accurate cost comparisons.
Can I ignore packaging costs for small batches?
Small costs multiply fast across batches. At €0.50 extra packaging per batch over 100 monthly batches, you're looking at €600 annually in unaccounted expenses.
📚 Sources consulted
- EU Verordening 852/2004 — Levensmiddelenhygiëne (2004) — Official source
- EU Verordening 853/2004 — Hygiënevoorschriften voor levensmiddelen van dierlijke oorsprong (2004) — Official source
- EU Verordening 1169/2011 — Voedselinformatie aan consumenten (2011) — Official source
- NVWA — Hygiënecode voor de horeca (2024) — Official source
- NVWA — Allergenen in voedsel (2024) — Official source
- Codex Alimentarius — International Food Standards (2024) — Official source
- FSA — Safer food, better business (HACCP) (2024) — Official source
- BVL — Lebensmittelhygiene (HACCP) (2024) — Official source
- Warenwetbesluit Bereiding en behandeling van levensmiddelen (2024) — Official source
- WHO — Foodborne diseases estimates (2024) — Official source
Food Standards Agency (FSA) — https://www.food.gov.uk
The HACCP standards shown in this application are for informational purposes only. KitchenNmbrs does not guarantee that displayed values are current or complete. Always consult the FSA or your local authority for the latest regulations.
Written by
Jeffrey Smit
Founder & CEO of KitchenNmbrs
Jeffrey Smit built KitchenNmbrs from 8 years of hands-on experience as kitchen manager at 1NUL8 Group in Rotterdam. His mission: give every restaurant owner control over food cost.
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