Effect of heat treatment prior to extraction on the yield and quality of red fruit (Pandanus conoideus) oil

Abstract

The quality of red fruit (Pandanus conoideus) oil (RFO) was strongly influenced by the processing and extraction method. The effect of heat treatment of red fruit using steam pressure at 100, 110 and 120°C during 3-45 mins prior extraction using dry method, againts the oil yield, free fatty acid (FFA), total carotenoids and tocopherols of RFO were investigated, using experimental method. Heat treatment of the red fruit drupa (grains) using pressurized steam (autoclave) at the temperatures of 100, 110 and 120°C, with the pressure of 14.9 psi, for 3 to 45 mins before the oil is extracted by compression using Hydraulic Jack. Furthermore, RFO was analyzed for oil yield, FFA level, total content of carotenoids and tocopherols. The results showed that heating treatment prior extraction increased the oil yield, but decreased carotenoid and tocopherol content. Heating treatment also increased the FFA levels; but tend to decrease with the increasing of temperature and heating time. The minimum FFA level was obtained from heat treatment at 120°C for 20 mins, with the highest oil yield (11.5±0.3% of total grains extracted), and the carotenoids and tocopherols content of 6148±65 ppm and 1515±24 ppm, respectively, as well as the FFA level of 0.76±0.1%, no significant difference (P<0.05) with the control (0.71±0.2%). To further reduce the FFA content, it is recommended to study the effects of heat treatment of red fruit immediately after harvest.