Breaking in Burrs
I was reading James Hoffman’s blog on the burrs for espresso grinders and how long it takes to break them in. http://www.jimseven.com/2011/06/15/dear-grinder-manufacturers/
He had a mini rant that was intended to get signatures from other coffee pros who could put pressure on grinder and more particularly burr manufacturers to produce products that are ready to go when you buy them.
I have long known that coffee grinders need to have some coffee run through them before they work their best. This is a fairly widely held belief and I buy it (although I have no solid proof). The thing that blew me away, though, was the quantity of coffee that Hoffman claimed needed to run through the grinder to break it in. Here is the quote… “Grinder burrs should not require seasoning. The fact that the cutting edges are not clean and smooth, and take between 5 and 25 kilos of coffee to act as intended, is unacceptable. They are selling an unfinished product and leaving it to those of us who care enough to bother to maintain the equipment to pick up the bill for getting them up to spec.”
that is a staggering figure if they take 5 to 25 kilos. That means roughly 10 to 50 pounds of coffee. Most home users will take years, not days to go through 50 pounds of coffee. Does this mean that if we have a Mazzer, Macap, etc type of grinder, our grinders are not ready the first year or so we use it? I have always tried to run about 5 pounds through a grinder, but I cannot imagine running 50 pounds through simply intended as waste.
It is worthy of note that Hoffman is one of the world’s leading experts on coffee and he tends to test everything he posts – he has a scientific bent that I love.
I counted 100 signatures before I quit counting and that was only about one fifth of the way down the page. In other words a lot of people agree with him. The only disagreement I saw was someone saying that Mahlkoenig grinders and ceramic burr grinders do not have this issue (someone that I think works for them so they may be right or they may be biased).
If the first 50 lbs might be less than ideal it makes me wonder, what is the lifespan of a set of burrs on a commercial grinder like a Mazzer? I always assumed that it was enough that I would almost never have to change them since they are intended for a café, which uses as much coffee in a week as I do in a year (or depending on the café life?)