A can 1 for foodstuffs is detailed which comprises a metal side wall 2 with a high dielectric strength isolating surface or layer 8,4, and metal end(s). A central part of an end(s) has an electrically conductive surface or layer and a peripheral part of an end(s) has an electrically isolating high dielectric strength surface or layer, and a conformable sealing layer. The sealing layer may itself be made from a high dielectric strength electrically isolating material, the end(s) and the side wall and the sealing layer 9 co-formed in a double seam seal (figure 1). An electric field can be applied to result in joule pasteurizing or sterilizing of the contents of the can. The can may be subjected to a voltage of up to 5000V at one end to produce the heating effect. A combination of voltages can be applied to cause joule heating and electroporation.
