Rosemary (Rosmarinus officinalis L.): Impact of drying on its flavor quality

Rosemary, a hard stemmed herb, is characterized by an aroma similar to pine. Twenty-five components of Indian rosemary oil have been identified by GC and GC-MS analysis. Fresh rosemary volatiles contained 75-80% oxygenated terpenes which included, a character-impact compound, verbenone, in a high concentration of 5.7%. Fresh rosemary leaves were subjected to convection (45C) and microwave (175, 385 and 595 Watts) drying and the attended effect on flavor components is reported. Despite faster drying and good color retention, the microwave drying was not useful to dry and preserve the herb due to heavy loss of volatile oil during drying.