Reflections on local food and climate change

As a climate change solution, the issue of "food miles" is one we should have cleared up a while ago.  In this blog we take a closer look at local food, climate change and wider sustainability issues.

When we work with food service business, and indeed with consumers in general, we see a number of misunderstandings about food sustainability.  Three common ones that we see are:

  • packaging-free food is always best
  • fresh food is better than frozen
  • local food is more sustainable and climate-smart

We are not going to go into all of these in detail, and we will cover the packaging and the fresh vs frozen issues at a later date.  But I do think its important that we shed some light on the data behind local food and its sustainability.  Disclaimer: I am not anti local food per se, but I do take the position that supporting farmers should be a global concept, not a local one.  But regardless of that, let's look at the arguments for and against local food.

food miles problem.png

The arguments for local food

  • Less travel = less carbon emitted to get food from A to B
  • Air travel is especially carbon intensive
  • Local food means supporting your local farmer (food sovereignty)
  • Local food means you know you where your food comes from (traceability)

The arguments against local food

  • Most carbon emissions in fact occur at the production stage, especially for livestock
  • Efficient transport systems are not just about actual distance from A to B
  • Knowing where your food has come from does not necessarily mean you know anything more about how sustainably it has been produced
  • Sustainability is a global problem, and this is no time for protectionism

The last two points for both "for" and "against" are of course very much dependent on context, but I would argue that currently the industry does not really have enough data to be able to say "because the food comes from a farmer near me, then I know more about the sustainability of that food".   For some food services this is perhaps achievable, but the workload required to actually do it properly puts it beyond the reach of many.

So let's look in more detail at the first two points, and the carbon emissions associated with the actual transport.

Different impacts for different forms of transport

At IntoFood we have done a lot of work with research groups in order to understand the carbon emissions of transport via road, boat, rail and plane.  In summary, boat or rail transport has a lower carbon footprint per kg of food than road transport; air transport has a much higher carbon footprint than all of them.  For boat/rail vs road, this is about volumes and efficiency: you can fit more food on a boat or train and this counteracts the fuel requirements per km.  For air transport, the fuel usage blows everything else out of the water.

So there is an argument that the shorter the distance, the lower the potential carbon footprint.  But that only holds true to a certain extent.  A local food distribution system via a small van can be much less efficient than a longer distance truck system that is optimised for efficiency.  So local does not really mean better. 

Transport impacts vs the bigger picture

The bigger issue of course is that most of the total emissions occur at the production stage, especially for livestock.  If we want to make sustainable choices, we need to look at the bigger picture.  We don't eat "1 kg of carrots" or "1 kg of pork"; we eat meals made up of different amounts of ingredients.  So if we are to eat more climate-smart, it is this and our daily eating patterns that matter.  This is illustrated via the different carbon emissions associated with an example meal below: a pasta dish with 120g of pork, some pasta and some vegetables.

comparison transport.png

A pasta dish that is "ultra local",  assuming zero carbon emissions from transport however unrealistic that might be, can be compared to a pasta dish where all the ingredients have come been transported 1000 km by road, and against the same meal where the ingredients have traveled 1000 km by plane.  As you can see, the "1000 km by road" scenario (the middle column) really does not add anything significant to the total carbon footprint compared to the "ultra local" pork pasta dish (the left column).  This is because the production emissions from pork are high, so in reality the pork dictates whether the dish is climate-smart or not.  Transport by plane makes a much bigger distance however (the right column).

Take away message?  

For road (and boat/rail) transport, the ingredients of your meal are much more important than whether it is local or not.  But this is not the case for air transport; air transport matters.

Transport impacts vs less meat

So now let's look at this meal in terms of the best leverage points to make it more sustainable.

Below you will see the same graph, plus a new column showing the carbon emissions associated with the same pasta dish but with 20% less pork and more vegetables.  As you can see, the reduction in emissions compared to the original pasta dish is pretty big.  In fact this reduction could only be achieved via a "local food" solution is all of the ingredients traveled 6000 km less by road.  Which is a nonsense concept. 

comparison transport with less meat.png

Take away message?

If you want to reduce the impact of a meal, then your main leverage point concerns the amount of "high impact" ingredients in that meal.  In most cases, this means how much animal-based food you use.  Again, air transport is a different case.  In all cases, of course, using less meat absolutely will make a difference.

Looking at sourcing as a whole

Ok, so this seems a pretty solid case for a meal-by-meal comparison.  But what about looking at your procurement and sourcing more generally?  A lot of noise is made about sustainable sourcing and often this includes overtones of "buy local".  But if we apply the same concept here to total procurement, how much does transport really matter?

We took anonymised data from staff restaurants serving on average 200 guests per day.  We then calculated that if they bought exactly the same food, but all of it traveled 1000 fewer km by road, then the carbon footprint would only be reduced by about 2%.  However, if they used 20% less meat with no change to sourcing, then they would reduce their carbon footprint by 10%. 

So which way do you want to go?  Real emission cuts through changing what you buy, or hard-to-implement and dubious impacts from local sourcing policies?  Of course you can do both, but you can't really make big claims about your local sourcing being a meaningful climate change benefit.  Support your local farmers by all means, but if your pork and your carrots are from farmer joe down the road, it is buying less pork that counts most with environmental impacts.