**4. Conclusions**

156 Distillation – Advances from Modeling to Applications

Fig. 15. Change of essential oil composition of main compounds during steam distillation of

Fig. 16. Change of essential oil composition of main compounds during steam distillation of

Roman chamomile (habitat Oberlungitz, first cut, fresh plant)

Roman chamomile (habitat Oberlungitz, first cut, drug)

Based on the sampling during the steam distillation process of the two essential oils changes in the composition of the oils were observed during distillation. Thus, the achievable relative content of individual compounds of the essential oil depending on the plant (plant part) can be optimized. Additionally other plants and their essential oils were investigated. This might be of importance for future product developments, if specific essential oil compositions are required. In most cases the pilot plant scale distillation must not exceed 60 minutes distillation time, because after this period only very small amounts of essential oils are generated. That fact would not justify a longer distillation process for economic reasons.
