A method includes optically interacting a bulk material or powder stored in a hopper with an integrated computational element ("ICE") configured to detect a characteristic of the bulk material or powder. The method also includes generating an output signal corresponding to the characteristic of the bulk material or powder, and receiving and processing the output signal with a signal processor to yield a value for the characteristic of the bulk material or powder. Also, the method includes transmitting a message flagging the hopper when it is determined that the bulk material or powder is not suitable for usage.
