OPINION: Last month, we reflected on the changes expected to anaerobic digestion (AD) in the UK, because of the Food Waste Reforms. We speculated, alongside others in the industry, whether the trend of increasing gate fees for AD will continue with the increase in demand. And whilst it’s too early to draw conclusions, it is perhaps timely to consider anaerobic digestion’s place in the treatment of food waste, when pitched against other options.
Any food safe for human consumption should be redistributed to those in need
It goes without saying, that at the top of the hierarchy should be the redistribution of food to those who need it. In both the UK and across the globe, we see unacceptable levels of food poverty alongside amazing charities that help bridge this gap. But what we’re really talking about here is surplus food – edible produce where supply exceeds a specific, intended demand. Food waste in its truest sense is typically not fit for human consumption – at least under current food safety regulations.
The amount of food waste still going to landfill might surprise you
Despite efforts, food waste is still one of the largest components of landfill waste worldwide. Of course, in respect of municipal waste we should expect this to reduce as local authorities roll out specific food waste collections, however for commercial waste there is still a lack of knowledge around alternatives, alongside some very real commercial pressures. As a result, complete produce can be sent to landfill simply because it’s too costly to do anything with – and rising gate fees for AD plants won’t help this.
But why does it matter? Firstly, the decomposition of food waste in this way causes methane, a greenhouse gas far more potent than CO2 over short timescales. But it will also often still be packaged, adding materials to landfill that won’t decompose and could have otherwise been sent for onward recycling.
Whilst there’s consensus that repurposing food waste makes more sense, the options are not always fully explored
Food waste, particularly that from supermarkets or similar commercial entities, tends to be separated into two lines: fresh produce and bakery. As a feedstock within anaerobic digestion, bakery waste produces the best yields, but will often be combined with fresh produce as part of a wider commercial arrangement, and/or to stabilise digestion.
Taken in isolation, bakery waste would need mixing into wet produce or to have water added for the purpose of anaerobic digestion – an additional cost consideration against the backdrop of rising fees.
However sometimes overlooked is that option for bakery waste to be used for animal feed – in fact, it can even attract greater value in this market, being sold on to animal feed manufacturers who either blend the recovered food into traditional animal feed, or into its own recipe.
So, if you create or process bakery waste, animal feed may be the better option
Anaerobic digestion plays a central role in the treatment of food waste, but it’s not the only solution. From a circular economy perspective, animal feed keeps the material within the food chain longer, it prioritises nutrient recovery, avoids additional feed crops, and may be more commercially viable.
So, what prevents it? For both options, removing the outer packaging is crucial and this is where a depackaging machine comes in. For bakery waste being used for animal feed, this process must be sufficiently gentle to protect the nutrients, but many hammermill machines (used for broader purposes) are far too aggressive for this job, only doing a sufficient enough job anaerobic digestion. In turn, waste processing plants may be limited by their technology.
Interested in finding out more about food waste and organics? Come to the letsrecycle.com National Food Waste Conference in London TOMORROW (19 March 2026). Find out more and buy tickets here.
