What You Need to Know
During heating to 180–200 °C, the oil’s temperature ruptures seed cell walls, allowing volatile sulfur compounds such as allyl isothiocyanate and fenugreek isothiocyanates to vaporize and dissolve into the oil matrix. The process is analogous to a Maillard‑like reaction, where heat‑induced breakdown of glucosinolates yields pungent isothiocyanates that impart characteristic flavor and aroma. Precise control of temperature and exposure time prevents oxidation of these compounds, which would otherwise produce bitter, acrid off‑flavors.
The Science
Primary Reaction
thermal extraction and release of volatile isothiocyanates and essential oils into oil