Picture this: you're trimming 10kg of ribeye and watching 3kg of bones, fat, and cartilage head straight for the bin. That's €75 walking out your kitchen door. But bones, cartilage and fat transform into liquid gold for stock or soup, turning waste into profit.
Why calculating trim waste matters
Every time you trim a steak, you're making a choice - toss money in the trash or turn scraps into revenue. Using waste for stock or daily soup transforms costs into actual income. The difference? Hundreds of euros saved monthly.
💡 Example:
You buy 10 kg of ribeye for €25/kg = €250. After trimming you have:
- 7 kg of quality steak (sellable)
- 3 kg of trim waste (bones, fat, cartilage)
Without reuse: €75 waste (30% of your purchase)
With reuse: €75 becomes value for stock
The basic formula for trim waste savings
Calculate savings by comparing what you'd pay for equivalent value elsewhere:
Savings = Weight of trim waste × Alternative purchase price - Processing costs
Processing costs are mainly labor: time spent transforming waste into stock or soup.
💡 Concrete calculation:
3 kg of trim waste becomes 12 liters of beef stock:
- Alternative: bouillon cubes at €8/liter = €96
- Processing costs: 2 hours labor at €20 = €40
Net savings: €96 - €40 = €56 per 10 kg meat
Impact on your food cost
Reusing trim waste lowers the actual purchase price of your main product. After managing kitchen operations for nearly a decade, I've seen this move the needle significantly:
- Original purchase price: €25/kg
- Savings per kg: €56 ÷ 10 kg = €5.60/kg
- Actual purchase price: €25 - €5.60 = €19.40/kg
Your food cost on steaks drops 22% immediately. No price cuts needed.
⚠️ Note:
Only count what you actually use. Stock sitting unused equals extra costs, not savings.
Different types of trim waste and their value
Not all scraps are created equal. Here's what different trim waste brings to the table:
- Beef bones: €3-5/kg value in stock (vs €8-12/liter ready-made)
- Chicken bones: €2-3/kg value in broth
- Fish bones/heads: €4-6/kg value in fish stock
- Vegetable trimmings: €1-2/kg value in vegetable broth
💡 Restaurant practice example:
Restaurant with 200 covers/week, uses per week:
- 15 kg of beef trim waste → 60 liters of stock
- Alternative costs: €480 (ready-made stock)
- Processing costs: €80 (4 hours labor)
Weekly savings: €400 = €20,800/year
How to track this in your administration
Accurate cost price calculation requires recording these savings systematically:
- Record trim waste produced per purchase
- Track stock/soup output from waste
- Calculate alternative value (what would you buy instead?)
- Subtract processing costs
- Distribute net savings across main products
Tools like KitchenNmbrs automate this calculation by adding savings as a 'negative ingredient' to your recipes.
How do you calculate trim waste savings? (step by step)
Measure your trim waste per purchase
Weigh the waste that results from processing your main product. Note the weight and type (bones, fat, cartilage). Do this a few times to get an average.
Calculate the alternative value
Find out what you'd pay for a comparable product. For beef bones: what does ready-made beef stock cost per liter? For vegetable scraps: what does vegetable broth cost?
Subtract processing costs
Calculate how much time (and therefore money) it costs to process the waste. Multiply the hours by your kitchen labor rate. Subtract this from the alternative value.
Distribute across your main products
Divide the net savings by the weight of your main product. This gives you the savings per kilo, which you can subtract from your purchase price for cost price calculations.
✨ Pro tip
Track one protein's trim waste for exactly 4 weeks to establish your baseline. If you're consistently saving €150+ monthly from that single source, expand tracking to all proteins.
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 count labor time when processing trim waste?
Absolutely - otherwise your numbers won't reflect reality. Two hours making stock costs €40-50 in labor. Subtract this from the value you create or you'll overestimate savings.
What if I don't sell all the stock or soup I make?
Then you've got extra costs, not savings. Only count stock actually used in dishes you sell. Everything else remains waste, just in liquid form.
How do I prevent my stock from spoiling before I use it?
Make smaller batches or freeze portions in usable quantities. Frozen stock lasts 3-6 months. Factor freezing costs into your calculations though.
Can I include this saving in my food cost calculation?
Yes, subtract savings from your purchase price to get actual cost price. This directly lowers your food cost percentage on dishes using the main product.
Which trim waste has the highest value for reuse?
Beef bones and fish bones typically deliver maximum value. Fish stock costs €10-15/liter ready-made, beef stock €8-12/liter. Vegetable scraps offer less financial return.
How much trim waste should I expect from different proteins?
Whole chickens yield 20-25% trim waste, beef primals around 15-30%, whole fish 40-50%. Track your actual percentages since butchering skills affect these numbers significantly.
📚 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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