Every professional kitchen — restaurant, hotel, hospital, kindergarten, canteen — produces food residues daily: trimmings, grounds, plate returns, expired preparation. In the EU, restaurants and food services account for 11 % of all wasted food, around 14 kg per inhabitant per year (Eurostat). Regulation is tightening: the revised Waste Framework Directive (EU) 2025/1892 makes Member States legally accountable for a 30 % per-capita reduction by 2030, with restaurants and hospitality explicitly included; in France separate collection has been mandatory for everyone since 1 January 2024, and in England the obligation extends to the smallest firms by 31 March 2027.
If you are asking "where does it all go?", there are six routes. They differ in the three things that decide the cost: what remains after treatment, who pays for it — and for how long.
1. Conventional hauling (bins + licensed collector)
Residues are collected in bins that a licensed hauler empties on a schedule. No equipment investment, but a permanent cost of bin rental and every collection, floor space the bins occupy, and odour and hygiene between two pickups. The cost grows with volume — and never stops.
2. On-site composting (electric composters)
Machines that turn residues into a dry, compost-like material using heat and mixing — manufacturers state volume reductions of up to 90 % within 24 hours. The key question: a solid output remains at the end of the process, and someone has to take it away or use it, so part of the logistics (and cost) returns through the back door. Special rules govern the status of that output as fertiliser.
3. Dehydrators (driers)
They remove water — the largest share of the mass — with heat. The result is a much lighter dry residue, but the price is heating energy and, again, a solid that still needs disposal. A dehydrator shrinks the transport problem; it does not remove it.
4. Food waste disposers (grinding to drain)
They grind residues directly into the sewer, without biological breakdown. Simple in the kitchen, but the entire load shifts to the drainage system and the treatment plant; local rules and water utilities therefore often restrict or condition their use for commercial volumes. Check local regulations before considering one.
5. Tank systems with tanker collection
Residues are ground and stored in a sealed tank; according to the manufacturers of such systems a tanker empties it typically every 4–6 weeks and takes the contents to a biogas plant. Hygienic and automated — with a permanent recurring cost of transporting the entire mass (including the water that makes up most of it) and dependence on external logistics.
6. On-site aerobic digestion
Microorganisms break residues down continuously in the presence of oxygen; the output is a liquid effluent that leaves through the existing drain (confirm discharge conditions with your local water utility). No solid output, no stored mass, no collection schedule. Griffon digesters run without a heating stage, keeping energy consumption low, and their CO₂ emissions per tonne of treated residues were measured in the 2022 University of Zagreb study. They are manufactured in the EU — CE conformity, available service and short supply routes.
How to choose
Three questions narrow the choice: (1) What remains after treatment and who takes it? (2) Which cost is permanent and which one-off? (3) Do local rules allow discharge, or do you need permits? In the food-use hierarchy, after donating usable food, treatment at the point of origin is the most desirable option — precisely the category in which aerobic digestion operates.
For the numbers for your kitchen — volumes, savings and payback — use our sizing calculator, and a detailed technical comparison of all categories is on the comparison page.
Sources: Eurostat (food waste estimates, sector shares); Directive (EU) 2025/1892; ecologie.gouv.fr (tri à la source, loi AGEC); gov.uk (Simpler Recycling); University of Zagreb study (2022). Performance data for competing categories: as stated by their manufacturers. Regulatory obligations depend on your circumstances — confirm them with the competent authorities.