I have had the same problem with a FoodSaver device. All the exterior black plastic surfaces except the bottom developed this sticky GOOK. I tried alcohol then CitraSolv (which may be concentrated GooGOne) ... didn't help at first but a few hours later hubby got it clean, with alcohol paper towels and lots of elbow grease. Methinks there must have been residual CitraSolv doing something in the meantime - the wipe job had been less than thorough.