Professional deformations of economics, part whatever it is
Via Felix Salmon, Tim Harford, "The Undercover Economist"[1] writes on how importing food isn't a bad thing. Not so bad as far as it goes, but he misses the most important point in any analysis of food miles, which is the one Alex picked up - the concept of food miles is pretty much totally incoherent, as a great deal of this stuff is picked up as a backload. It's not surprising that a conventionally-trained economist would have missed it, because backloads are surprisingly difficult to integrate into any normal economic model - it's certainly worth remembering that you don't need to tell debatable stories about QWERTY keyboards to get into trouble, because there are big issues of nonlinearities and nonconstant returns to scale in a simple trucking route.
[1]Basically the Tommy Steele of Freakonomics. Not as irritating as L&D but still IMO a Bad Thing for the science. The only one of these books I've got time for is the Robert Frank one, precisely because it ties the whole science of economics down to specific problems with case-specific solutions (and then tries to generalise) rather than developing a set of generic solutions and then trying to force-fit the problems into them.
Even more fundamentally, as Clive Bates of Bacon Butty points out, "food miles" doesn't take into account the difference in costs (of every kind) between things of different weight. Frankly, who cares if the one container of yeast that will keep the bakers going all year came a long way?
ReplyDeleteI'm missing something here aren't I - why would you ship a container-load of yeast around the place rather than shipping a little bit of yeast and then growing it when it got here? Actually, thinking about it, I don't believe that you can ship yeast about in containers; over the course of a week's journey it would either die or quadruple in size, while giving off loads of CO2 and alcohol. I suppose you could freeze it but this seems hell of an expensive given that the stuff is really cheap.
ReplyDeleteI don't think a single container of yeast would keep us going all that long btw; bread is about 1% yeast, isn't it? So the Co-Op bakery would use about a shipping container's worth of yeast a day, although as I say, I don't believe they do ship it.
I see your point, but I am now obsessed with getting to the bottom of this yeast thing. I once drew up a model of what the futures market for yeast would look like in order to teach young bankers about contango and backwardation.
Ahhh I see, following the links back to the original Ecologist article - they don't ship yeast around the place, but the yeast is fed on molasses, which gets shipped from sugar-producing countries.
ReplyDeleteThat's asinine. Molasses is a byproduct of sugar production (another backload-type problem, hurray!). Presumably their alternative would have been to leave the molasses where it was. Molasses is a really horrible pollution problem - the sugar producers would have to get rid of it in some fashion. I don't think you can even make biofuel-grade ethanol out of the stuff (and even if you could, you would still be left with a load of toxic molasses-yeast sludge, plus it's not obvious where they would get the water from).
I'm not sure this problem is insurmountable - you could come up with some sort of scheme for weighting the miles by their contribution to the weight or calorie content of the food - but it's always going to be a pointless exercise; ever since Kantorovich we've known that prices only make sense as indices of scarcity. And since what we actually care about is the carbon dioxide which can be taxed anyway, I don't see what food miles are adding to the party.
bread is about 1% yeast, isn't it? So the Co-Op bakery would use about a shipping container's worth of yeast a day
ReplyDeletethis might be the least accurate guesstimate I have ever made.
Actually, thinking about it, I don't believe that you can ship yeast about in containers; over the course of a week's journey it would either die or quadruple in size, while giving off loads of CO2 and alcohol. I suppose you could freeze it but this seems hell of an expensive given that the stuff is really cheap.
ReplyDeleteSee, this is the problem with economics generally. You get highly educated people opining on the economics of the food industry who have manifestly no idea how to bake bread. Shipping live yeast culture around the place. Sheesh.
You can dry yeast out to form little granules, like instant coffee (which is freeze-dried). It lasts for ages. When you want to use it for bread, you mix it with warm water and a bit of sugar, and it starts fermenting again, then you mix it into the flour.
At about 5g (more or less) dry yeast to a loaf, a container load of yeast would make four million loaves. That's some Co-Op bakery.
At about 5g (more or less) dry yeast to a loaf, a container load of yeast would make four million loaves. That's some Co-Op bakery.
ReplyDeleteOh, I wasn't so far off then - the old Co-operative Wholesale Society bakery (since sold off I think) used to bake 2m loaves a day. Total UK bread consumption is apparently 9m loaves (presumably with some kind of boe measure to account for baps and baguettes)
ahh, dried yeast, I see. Although as far as I can see the UK does in fact manufacture yeast domestically rather than importing it from molasses-producing countries; presumably this is because yeast has a low value density, so I think my analysis still goes through.