Solution : https://service.sap.com/sap/support/notes/623791 (SAP Service marketplace login required)
Key words : 
-product detail view, start transaction se51, line afpod gsber, afpod-gsber, transaction omj7, process order, production order, business area, set automatically, terms cor1
Related Notes : 
       
| 197536 | Business area is missing for co-products |