Making essential oils involves the distillation application that can be roughly divided into four groups: laboratory scale, industrial distillation, perfume and medicinal plant distillation, and food processing. The latter two are significantly different from the two preceding ones, as distillation is not used as a true purification method, but rather to transfer all fluctuations from source materials to distillation in beverage and plant processing.
The main difference between laboratory-scale distillation and industrial distillation is that laboratory-scale distillation is often performed on a group basis, while industrial distillation often occurs continuously. In group distillation, the composition of the source material, the vapor of the distillate compounds, and the change of distillation during distillation. In batch distillation, a season is loaded with a pile of food mixture, which is then divided into fractions of its component, which are sequentially collected from the most volatile to the least volatile, with bottoms – smaller or non-volatile part – removed at the bottom. It can still be recharged and the process repeated.
In continuous distillation, the source materials, vapor, and distillation are maintained in a continuous composition by carefully replenishing the source material and removing fractions from both the steam and the fluid in the system. This results in a more detailed control of the separation process.