Seasonal dishes have fluctuating purchase prices that can make or break your profitability. Many restaurant owners calculate cost prices once and forget to adjust them, losing money without realizing it.
Seasonal dishes have fluctuating purchase prices that can make or break your profitability. Many restaurant owners calculate cost prices once and forget to adjust them, losing money without realizing it. In this article, you'll learn how to track cost prices dynamically and protect your margins.
Why seasonal dishes are risky
Asparagus costs €18 per kilo in April, €8 per kilo in May. If you base your menu price on the cheap May price, you lose €10 per kilo in April without noticing.
⚠️ Watch out:
With seasonal products, purchase prices can fluctuate 200-400% within a few weeks. Your food cost can jump from 25% to 45% without you noticing.
The dynamic cost price formula
For seasonal dishes, use a weighted average cost price based on expected sales per period:
Weighted cost price = (Period 1 × Price 1 × Volume 1 + Period 2 × Price 2 × Volume 2) / Total volume
💡 Example: Asparagus risotto season
You sell 200 portions in 3 months:
- April (50 portions): €18/kg asparagus
- May (100 portions): €8/kg asparagus
- June (50 portions): €12/kg asparagus
Weighted price: (50×€18 + 100×€8 + 50×€12) / 200 = €11.50/kg
Calculate with €11.50/kg instead of the daily price
Set up weekly price monitoring
Check the prices of your 3 most important seasonal ingredients with your supplier every Monday. Record these in an overview with:
- Ingredient name
- Current price per kg/liter
- Previous week price
- Difference in percentage
- Impact on dish cost price
💡 Example: Monitoring overview
Week 15 vs Week 14:
- Asparagus: €15/kg → €12/kg (-20%)
- Strawberries: €8/kg → €6/kg (-25%)
- Zucchini blossom: €45/kg → €38/kg (-16%)
Spring risotto cost price drops from €8.50 to €7.20
When to adjust your menu price
Adjust your selling price if the cost price changes more than 15% compared to your calculated average. For smaller changes, your margin absorbs the fluctuation.
⚠️ Watch out:
Never adjust your menu price every week. Guests expect price stability. Use a bandwidth of 15-20% before you take action.
Build in safety margins
For seasonal dishes, calculate with a slightly lower desired food cost to absorb price fluctuations:
- Regular dishes: 28-32% food cost
- Seasonal dishes: 25-28% food cost
- High-risk season (short/expensive): 22-25% food cost
💡 Example: Safety margin calculation
Asparagus risotto with weighted cost price €11.50:
- At 32% food cost: €11.50 / 0.32 = €35.94 excl. VAT
- At 25% food cost: €11.50 / 0.25 = €46.00 excl. VAT
The lower food cost gives you €10 buffer for price fluctuations
Digital tools for price monitoring
Manually tracking changing prices takes a lot of time and is error-prone. A system like KitchenNmbrs lets you quickly update ingredient prices and shows the direct impact on your cost prices.
You see at a glance which dishes exceed your desired food cost and can take action immediately.
How do you calculate cost prices of seasonal dishes?
Analyze the seasonal pattern
Determine when you sell the dish and how many portions per period. Check your supplier's historical prices for the main ingredients over the past 2 years.
Calculate weighted average cost price
Multiply each period price by the expected volume and divide by total volume. This gives you a realistic average cost price for the entire season.
Set up weekly monitoring
Check the current prices with your supplier every Monday. Note changes larger than 15% and calculate the impact on your cost price per dish.
Build in safety margins
Calculate with 3-5 percentage points lower food cost than normal to absorb price fluctuations without having to adjust your menu price immediately.
Adjust menu price for large deviations
If your cost price deviates more than 15% from your calculated average, adjust your selling price. Your safety margin absorbs smaller fluctuations.
✨ Pro tip
Make agreements with your supplier about price forecasts for the upcoming season. Many wholesalers can provide indications of expected price developments, which helps with your planning.
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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
How often should I check the prices of seasonal ingredients?
Check at least weekly, preferably every Monday. For very volatile products like asparagus at the beginning of the season, you might want to check twice a week.
Should I adjust my menu price every week if ingredients become more expensive?
No, only adjust your menu price for changes larger than 15%. Guests expect price stability. Use safety margins to absorb small fluctuations.
How do I calculate the impact of price changes on my total cost price?
Calculate how many grams/ml of the changed ingredient goes into one portion. Multiply by the price difference per kg/liter. This gives the impact per portion on your cost price.
Can't I just use a fixed markup on the daily price?
That doesn't work well because you'll be too expensive when prices are low and lose money when prices are high. A weighted average provides more price stability.
What safety margin should I maintain for seasonal dishes?
Calculate with 3-5 percentage points lower food cost than normal. For very volatile ingredients like truffles or asparagus, you can maintain up to 7 percentage points lower food cost.
How do I prevent losing money on seasonal dishes?
Monitor weekly, use weighted average prices, build in safety margins, and adjust your menu price in time. Stop selling if the cost price becomes too high.
📚 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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