Hey everybody, out of curiousity, does using the trowel/trier whilst roasting screw with the roast? I see quite few IG videos and stories of roasters pulling out the trier to smell and see the beans etc, but i always thought that if you’re removing beans from the roasting process and introducing them to much cooler air; you’re completely ruining those beans, and if you do it enough times during a roast you can wind up having a small percentage of that roast being less developed than the rest. But i also don’t know if that theory has any merit at all. would be cool to see if anyoneelse has thought about this and has any data to add
…I wouldn’t worry too much about it for a couple of reasons. Most commercial roasting is done in quite large batches compared to the beans pulled out by a trier. Even a 5 kg. machine with a 3 kg. batch is quite large compared to the couple of grams that would fall into the trier. We’re talking degree changes here that are so minor, they are (in my opinion, don’t send me hate mail…) insignificant. Secondly, when the beans in the trier go back in the drum or ‘bed’ of beans, they’re immediately dispersed and the temperature fluctuation would be nearly undetectable. I wouldn’t get caught up in the minutia here, it’s like changing the temperature on your espresso machine 0.2 degrees and expecting game changing results…
Also, a number of roasters are using advanced software to replicate roast profiles on a consistent basis. This might take away the need to use a trier constantly as you’ve eliminated some of the variables and have a reasonable expectation of the key events of any given roast (1C, RoR, DTR, etc.) based on previous and historical data.
I suppose in home roasting (think Behmor…), if you were to constantly open the door, this would almost certainly have a negative impact on your roast due to the smaller batch size and much smaller volume of hot air and overall mass of the roaster (plastic, aluminium, sheet steel vs. cast iron).
Shawn Thacker, below, covered most of what I was thinking, but there is one more consideration that will help you rest easy on this score.
In any quality roaster, the trier has a lot of mass to it. Thus, holding the whole trier with a full load of beans out in the cool room aiir for the few seconds it takes to look and whiff does not allow the entire mass (trier and beans) to cool signficantly. In some of the cheaper roasters out there, the trier is made of pretty flimsy metal and thus does not have much mass Still, the load of beans is well protected from the room air, and still would not cool significantly.
I’d say roast away, pulling the trier as often as seems warranted to keep “up close and personal” with the develooping roast.