Roasting beans

[ap958]

Hi All,

I'm new here and have a question.

I have been roasting my own green arabica beans for a few months now and use a hot air popcorn maker (1500 watt) that does a great job of roasting while moving the beans around.

I do an 8 minute roast, but sometimes I notice an oily apperance of the bean. Other times a little round flat piece pops off the bean.

I don't particularly want a very dark roast and was wondering whats going on here?

I only make cappucino on a pumpdriven machine.

TIA


ap