I have a Fresh Roast SR500 home roaster and have had some success roasting mostly drinkable coffee. My first attempts, following the instructions enclosed with the roaster turned out horribly, tasting both charred and grassy at the same time. Yeechh. After doing some online reading, I've greatly lengthened the roasting process with mostly good results. I'm currently roasting batches of 90g of raw beans for between 12-17 minutes. My thinking is that this is giving the beans time for the proper reactions to take place inside the beans without charring the outside. But I've read that some commercial roasters might take 20 minutes or more to roast a batch. Of course they are roasting much larger quantities than I am but it occurred to me that perhaps this longer roasting time is intentional and has some beneficial effect.
I'm mostly aiming for a City or City+ roast level and want to know if lengthening the roast time beyond what I'm currently doing is a good idea? I would still stop the roast soon after First Crack, but I suppose I could stretch out the time to get there if that might produce a better product.