Here's something most restaurant owners don't realize until it hits their bottom line: packaging format changes can quietly destroy your profit margins. Your flour supplier switches from 5 kg bags to 6 kg ones, and suddenly your cost calculations are off. You must calculate exactly what this means for every recipe and margin.
Why packaging formats affect your cost price
A packaging change looks harmless but impacts three critical areas: your purchase price per kilo, inventory planning, and portion calculations. Your supplier moves from 5 kg to 6 kg packages? You're probably paying a different rate per kilo. And your recipes still reference the old quantities.
⚠️ Watch out:
Suppliers often offer discounts on larger packages. But sometimes they quietly raise the price per kilo while you think you're getting a better deal.
Step 1: Calculate the new price per kilo
Compare old versus new price per kilo. This matters because your recipes work with grams and kilos, not packages.
💡 Example:
Old situation: flour 5 kg for €12.50
- Price per kilo: €12.50 / 5 kg = €2.50/kg
New situation: flour 6 kg for €14.40
- Price per kilo: €14.40 / 6 kg = €2.40/kg
Difference: €0.10/kg cheaper
Use this formula: New price per kilo = Total price new package / New quantity in kg
Step 2: Calculate impact on your recipes
After managing kitchen operations for nearly a decade, I've learned that small ingredient cost changes compound quickly across high-volume dishes. Focus on your top-selling items that use this ingredient. Calculate grams per portion and determine the cost difference.
💡 Example:
Margherita pizza uses 180 grams of flour per pizza
- Old cost price flour: 0.18 kg × €2.50 = €0.45
- New cost price flour: 0.18 kg × €2.40 = €0.432
- Difference: €0.018 per pizza
At 200 pizzas per week you save: €0.018 × 200 × 52 = €187 per year
Formula per dish: Impact = Quantity per portion (kg) × Difference price per kg × Number of portions per year
Step 3: Check your inventory planning
Larger packages tie up more cash in inventory. Smaller ones mean ordering more frequently. Calculate what this costs in time and cashflow.
- Larger package: fewer order rounds, but more money tied up in inventory
- Smaller package: order more frequently, higher delivery costs, but less cash tied up
- Check: does the new package still fit in your storage?
💡 Example:
You use 20 kg flour per week
- Old situation: order 4 bags of 5 kg
- New situation: 3.33 bags of 6 kg → you need to order 4 bags
- You now buy 24 kg instead of 20 kg → 4 kg extra inventory
- Extra cashflow: 4 kg × €2.40 = €9.60 more tied up
Step 4: Calculate total impact
Add all effects together: cost price change, inventory change, and any additional delivery costs. This gives you the complete picture.
Use this checklist for each ingredient that changes packaging format:
- Compare price per kilo (old vs new)
- Calculate impact on your top dishes
- Calculate through inventory change
- Check storage impact (does it still fit?)
- Calculate total annual impact
⚠️ Watch out:
Update your recipes in your system with the new prices. Otherwise your food cost calculation won't be accurate and you'll make wrong decisions.
Tools that help
Manual calculations eat up valuable time. Especially when multiple suppliers change their packages simultaneously. Food cost management tools can quickly show you the impact on your cost price per dish.
You enter the new purchase price and the system automatically recalculates your food cost for all dishes using that ingredient. You immediately see where action is needed.
How do you calculate cost impact? (step by step)
Compare price per kilo
Divide the total price by the number of kilos for both the old and new package. Calculate the difference per kilo. This is your basis for all further calculations.
Calculate impact per dish
Take your 5 best-selling dishes that use this ingredient. Multiply the quantity per portion by the price difference per kilo. Add up how many portions you sell per year.
Check inventory and cashflow
Calculate how much extra or less inventory you need to hold. Larger packages mean more cash tied up, smaller packages mean ordering more frequently and possibly higher delivery costs.
✨ Pro tip
Update your recipe costs within 48 hours of any packaging format change, even if the price per kilo stays the same. I've seen restaurants operate with outdated cost data for months, making pricing decisions based on incorrect margins.
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
Should I always choose the larger package if it's cheaper per kilo?
Not always. Check if you can store the extra inventory and if you can spare the cashflow. Sometimes a slightly higher price per kilo is better for your liquidity.
How often should I update my cost prices after supplier changes?
Immediately after each change. Old prices in your system lead to incorrect food cost calculations and poor decisions about menu pricing and profitability.
What if my supplier changes both the package size and the unit price?
Calculate the new price per kilo first, then the impact on your dishes. Treat it as two separate changes: the package size adjustment and the price modification.
Can I track packaging format changes manually in Excel?
You can, but it's time-consuming and error-prone. With multiple suppliers and hundreds of ingredients, it becomes overwhelming quickly. Automated systems that recalculate instantly are more practical.
What if the new package format doesn't fit in my storage space?
Factor the costs of extra storage or more frequent ordering into your calculations. Sometimes a higher price per kilo costs less than solving storage problems.
How do I handle partial package usage in my cost calculations?
Calculate based on actual usage, not full packages. If you use 15 kg weekly but packages are 6 kg, you'll need 3 packages (18 kg total) with 3 kg leftover inventory.
Should I negotiate with suppliers about packaging format changes?
Absolutely. Suppliers often have flexibility, especially for high-volume customers. Present your storage constraints and cash flow concerns - they might offer alternative formats or adjusted pricing.
📚 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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