Postharvest management affects spearmint and calamint essential oils

Area of Science:

• Agronomy
• Plant Chemistry
• Postharvest Technology

Background:

• Investigated phytomass yield, essential oil (EO) content, and EO yield of Mentha spicata L. var. rubra, M. spicata L. var. viridis, and Calamintha nepeta Savi.
• Examined the impact of postharvest management on EO content and profile.

Purpose of the Study:

• To evaluate the phytomass yield, EO content, and EO yield of three aromatic species.
• To determine the effect of different postharvest treatments (fresh, dehumidified, oven-dried) on EO characteristics.

Main Methods:

• Field cultivation of Mentha spicata L. var. rubra, M. spicata L. var. viridis, and Calamintha nepeta Savi in Piedmont, Italy.
• Hydrodistillation of EO from fresh, dehumidified, and oven-dried plant material.
• Statistical analysis of phytomass yield, EO content, and EO yield data.

Main Results:

• Mentha spicata L. var. rubra exhibited the highest phytomass yield.
• Calamintha nepeta Savi yielded the highest essential oil (EO) content.
• Dehumidification significantly increased EO content compared to oven-drying, altering the EO profile.

Conclusions:

• Dehumidification is a promising postharvest technique for enhancing EO yield.
• This method can be beneficial for high-value aromatic species, provided the EO profile is acceptable.
• Postharvest management critically influences EO quantity and quality.