04-28-2018, 07:53 AM
IN ORDER to roll aluminium down to the thickness (or thinness) required for cooking foil (approximately 0.01mm), two coils of aluminium strip have to be passed through the rolling mill at the same time - a process called 'doubling'. The result is that the external side then has a shiny finish and the internal side is matt. The idea that the difference in finish enhances cooking is simply a marketing ploy by the foil producers, who could not make it shiny (or dull) on both sides even if they wanted to.