When people start thinking about food waste, they usually picture customers leaving food on plates. It's the visible stuff—the half-eaten steak, the abandoned side salad.
But in most kitchens, that's not where the bulk of waste actually happens.
The Numbers
WRAP's research across UK hospitality found that waste typically breaks down as:
- Prep waste: 45% — trim, peelings, over-production, mistakes
- Plate waste: 34% — what comes back uneaten from customers
- Spoilage: 21% — food that expires before use
These proportions vary by operation type. Quick-service restaurants tend to have more plate waste. Fine dining has more prep waste. Buffets have high plate waste and high over-production. But for most kitchens, prep waste is the biggest category.
Why Prep Waste Should Usually Come First
There's a practical reason to focus on prep waste before plate waste: you have complete control over it.
Plate waste involves customer behaviour. You can influence it with portion sizing, menu design, how food is described—but ultimately, you can't make someone clean their plate. There's always going to be some plate waste, and trying to eliminate it completely leads to tiny portions and unhappy customers.
Prep waste is entirely internal. It's your ordering, your storage, your techniques, your recipes. Every bit of prep waste is either a training opportunity, a process improvement, or a systems fix. There's no customer to negotiate with.
You also see results faster. Change a prep procedure and you see the effect in days. Change portion sizes and you might need weeks or months to understand the impact on sales, satisfaction, and actual waste.
When to Focus on Plate Waste Instead
That said, there are situations where plate waste is the bigger problem:
If your data shows it. Some operations genuinely have low prep waste and high plate waste. Don't assume—measure. If your plates are coming back half-full and your prep bins are light, address what the data actually shows.
If you run buffets. Buffet operations have both problems—over-production (prep waste) and customers taking more than they'll eat (plate waste). You need to work on both, but plate waste behaviour is often the more tractable issue through signage, smaller plates, and replenishment strategy.
If portion complaints are common. Customers complaining about portion sizes while also leaving lots of plate waste is a signal. You might be over-portioning specific items, or there might be sides people don't want but get automatically.
A Diagnostic Approach
Before deciding where to focus, spend a week actually measuring. Here's a simple approach:
For prep waste: Put a clear bin at each prep station for avoidable waste only (not bones, shells, unavoidable peelings). Weigh it at the end of each shift. Note what's in it.
For plate waste: Have a separate container for scraping plates. Weigh it by service period. If possible, note which dishes generate the most returns.
After a week, you'll have rough data on both. Look at:
- Which category is larger overall?
- Which has more variation (and therefore more room to improve)?
- Which would be easier to address with your current team and resources?
The Practical Interventions
For prep waste, the interventions are operational:
- Knife skills training
- Standardised prep procedures with documented yields
- Better storage and rotation
- Right-sized prep batches based on actual usage
- Using trim productively (stocks, staff meals, specials)
For plate waste, the interventions involve the customer experience:
- Reviewing portion sizes against what actually gets eaten
- Offering portion choices where appropriate
- Adjusting side dishes (many plate waste issues are unloved accompaniments)
- Better menu descriptions so customers know what they're ordering
- Doggy bags or takeaway options for leftovers
The Integrated View
Really effective waste reduction tackles both, but sequentially. Get prep waste under control first—it's faster, entirely within your control, and builds the measurement habits you'll need anyway. Then move to plate waste with a baseline established and momentum in place.
The kitchen that tries to fix everything at once usually fixes nothing. Pick your focus, make progress, then expand.
See what reduction could mean for your bottom line, or talk to us about a waste assessment for your operation.