malling wrote:
Rice is allot more dense and harder then roasted beans . - I would therefore expect such practices too shorten the life span of several components including the capacitor.

Especially with older Compack that had long been using to small capacitors, so with those grinders it would be a pretty bad idea to start grinding rice.

The newer models at least uses more powerful motor and larger capacitors, so you might get away with it for a while .