Effects of household-scale cooking on volatile compounds, sensory profile, and hypotensive effect of Kenikir (Cosmos caudatus)

Kenikir (Cosmos caudatus) can be used in the preparation of raw and cooked vegetables in some Indonesian dishes. The cooking process may affect the appearance, chemical properties, and flavor of kenikir. This study aims to determine the effect of household scale cooking on the volatile compounds, sensory profiles, and hypotensive activity of kenikir. Fresh kenikir samples and samples boiled or steamed at 100 ℃ (for 3 and 5 minutes) were analyzed for volatile compounds compositions (solid-phase microextraction-Gas chromatography-mass spectrometry, SPME-GCMS), sensory profiles by free choice profiling, and in-vivo study by using stroke-prone spontaneously hypertensive rats (SHRSP)—a model of spontaneous hypertension. The GCMS analysis identified 30 volatile compounds from 5 compound groups, namely alcohols (2 compounds), benzenes (3 compounds), esters (3 compounds), monoterpenes (10 compounds), and sesquiterpenes (12 compounds). Several compounds, namely (Z)-3-hexenol, α-cadinol, and 3-carene were only detected in fresh kenikir, whereas β-myrcene and β-elemene compounds were only identified after cooking. The principal component analysis of sensory attributes associated fresh kenikir with bright color and minty taste, steamed kenikir with floral aroma, and boiled kenikir with juicy, moist, tender, and smooth texture. Furthermore, a hypotensive effect was shown in the water extract of kenikir after 2 and 4 hours of single oral administration in SHRSP. In summary, the heating process (boiled and steamed) of kenikir has changed its volatile compound composition, which can affect its sensory profiles. In addition, the water extract of kenikir can diminish hypertension in SHRSP.