Every morning I roast 120 grams (about a quarter pound) in only six minutes.
There is no difference, that I can determine, between coffee that takes 6 minutes to roast compared to coffee that takes an hour or more to roast. As long as the coffee is roasting evenly throughout, the result should be the same.
Think of it like popcorn. Once the kernel “pops”, it’s done. Same with coffee, once the coffee “cracks” it is done and you are free to choose when to stop the roast based upon how you like your coffee roasted (light, medium, or dark). There are normally 2 cracks that occur when roasting. At any point after the first crack has ended, the coffee is ready. Letting the coffee continue to roast until the second crack is heard, will result in a darker roast. Roasting past second crack will result in an over-roasted (burned) coffee. Some people like it that way. The best way to determine when to stoo the toast is by using visual cues. What color suits you best? Light brown? Chocolate brown? Dark and oily? By choosing to roast your own coffee you get to decide!
I highly encourage everyone try, at least a few times, to roast their own coffee. It’s the surest way to create the best coffee you ever had!