Impact of post‐harvest drying on the volatile flavours of spiny coriander (Eryngium foetidum L.): Emphasis on fatty aldehyde reduction.

Spiny coriander (Eryngium foetidum L.) is a traditional food flavouring herb of tropics with coriander‐like odour. This study evaluated six different drying conditions (sun, shade, oven at 40°C and 60°C, microwave, freeze‐drying) for spiny coriander leaves, emphasizing on the drying time, essential oil yield and composition. Fatty aldehydes, especially trans‐2‐dodecenal, majorly abundant key aromatic flavour of spiny coriander underwent probable enzymatic reduction to alcohols upon long‐term oven‐drying, affecting the oil quality. Non‐conventional techniques like microwave and freeze‐drying, despite their certain advantages significantly reduced the oil yield (0.030%–0.031%) in comparison to fresh leaves (0.045%). Sun drying was found to be superior among the tested conditions, considering a reasonable drying time (4 h) and ability to retain the oil yield (0.043%), composition (quality) and chlorophyll content. It can be a sustainable drying technique for spiny coriander in the tropical region with abundant sunlight, especially for its value addition and commercialization in future. [ABSTRACT FROM AUTHOR]