Thermal and cooking properties of Indian medicinal rice Njavara in aqueous and milk media

Njavara is a medicinal red rice variety, is cooked with milk, dipped in herb extracts and topically massaged on the patient during panchakarma treatment. Pasting and thermal properties of dehusked Njavara rice flour in water and milk media were assessed and compared with two non-medicinal rice varieties PTB 39 (Jyothi) and IR 64. Solubility, swelling and X-ray diffraction pattern of Njavara rice flour were also analysed. Njavara showed high values for viscographic parameters in aqueous medium but least in milk medium, distinctive from the non-medicinal varieties. Thermal studies showed intermittent values of onset temperature (To), peak temperature (Tp) and enthalpy (ΔH) in both aqueous and milk media for Njavara. However, the gelatinization range (R) was more for Njavara. X-ray diffraction studies too showed intermittent crystallinity. The results showed that Njavara starch granules appear to be more compact at cooking temperature (98° C) compared to non-medicinal varieties and its high gelatinization range may facilitate the transfer of medicinal herb extracts to the body during topical massaging of Njavara treatment.