The Orange Jam Setting test is very important, we test jam thickness on the freezer cold plate. If the jam is watery, cook more. If the jam is sticky and seems setting that is the jam drop holds its shape without spreading too much. It is ready. Avoid overcooking of orange jam: Overcooking is when you cook jam to a level when sugar starts to caramelize and burn. So avoid cooking high heat and cook in a thick bottomed pan. Keep stirring at intervals and reduce heat towards the end.