Jasmine rice is a long-grain variety of fragrant rice (also known as aromatic rice). Its fragrance, reminiscent of pandan (Pandanus amaryllifolius) and popcorn, results from the rice plant’s natural production of aroma compounds, of which 2-acetyl-1-pyrroline is the most salient. In typical packaging and storage, these aroma compounds dissipate within a few months. This rapid loss of aromatic intensity leads many Southeast Asians and connoisseurs to prefer each year’s freshly harvested “new crop” of jasmine rice.
Thai jasmine rice and Cambodian rice share many of the same characteristics and grow mainly in neighboring geographic areas on opposite sides of the northeastern Thai-Cambodian border. Cambodian jasmine rice is cultivated in Cambodia and processed as white (milled and polished) and brown rice. Distinct Cambodian jasmine rice varieties include these three, phka rumduol, phka romeat, and phka rumdeng. Recent DNA fingerprint analysis, carried out with 18 markers, shows that all three varieties possess 18 known fragrance alleles. Two varietals (phka rumduol and phka rumdeng) are distinctly Cambodian with 17 markers in identical positions, with Thai jasmine rice and one fragrance marker each in a different position. The analysis of Cambodian phka romeat shows all 18 markers in identical positions with the trademarked Thai jasmine rice Thai hom mali.