Loss entry of Finished Products

Hi Friends!!!!!!!!!!!

In our industry we are producing Volatile finished products. After production we stored these finished products in storage tanks, but due to temprature it gets loss due to its volatile nature. As these products are excisable, we have to pay excise to central excise. In SAP how this storage wastage entry has to book so that stock get reduced & also how to capture the excise related entry? Please guide...............

Thanks

RAVI