Processing summer savory biomass for essential oil and further value added products

Abstract

Value-added prototypes were developed from summer savory, Satureja hortensis L., harvested at a local farm in the Annapolis Valley, Nova Scotia. The products were essential oil, air-dried spice powder and tisane derived from ‘plant top’ and ‘plant bottom’ material. The ‘plant top’ section represented secondary stem with leaves and flowers and the ‘plant bottom’ section represented primary stem and some secondary stem with leaf material. Samples were analyzed for their essential oil profile and polyphenolic content. Essential oil yields ranged from <0.1 to 1.0 g oil/100 g tissue. Seven compounds were identified in the essential oil profile with the two major compounds, γ-terpinene and carvacrol, representing about 85% of the compounds detected. Aqueous infusions of the tisane-like products contained relatively high amounts of carvacrol while a strong positive correlation (r²=0.9) was observed between carvacrol values and total phenolic content in spice formulations. This study has shown that summer savory grown in Eastern Canada is a good source of essential oil with high carvacrol content (36–49%). Tisane and spice products by air-drying methods are relatively inexpensive to prepare and could potentially command an acceptable value market price.

Keywords:

• summer savory
• value added products
• essential oil profile
• yield
• carvacrol
• polyphenolic content

Acknowledgement

This work was supported by the NSERC Engage Grants programme. We thank John and Heather Lohr of Farmer Johns Herbs for providing summer savory raw material and for their collaboration in this project