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Nutmeg is a native South East Asian plant which has medicinal properties. In this work, supercritical extraction was studied in order to obtain experimental data of the influence of pressure, temperature and particle size and in comparison to soxhlet extraction. Supercritical extraction was conducted at operating temperatures of 40, 50 and 60 °C, operating pressures of 20.7, 27.6, 34.5 and 41.4 MPa and dynamic extraction time was 90 min. The effect of three different sieved particle sizes ⩽0.500, ⩽1 mm and ⩽2 mm on the extraction yield was examined. The results show that the highest yield was 38.8 g oil/100 g sample obtained under extraction temperature of 60 °C, pressure 41.4 MPa using particle size of ⩽0.5 mm. Soxhlet extraction yields 34 g oil/100 g sample for 6 h of extraction time. The GCTOFMS shows that the supercritical extracts exhibited significantly higher aromatic ether group comparable to those obtained by soxhlet.

Palm kernel cake contains residual oil that has never been retrieved and it is treated as wastes. In this study, supercritical carbon dioxide was used to separate the oil from the palm kernel matrix. The studied extraction parameters were at the set pressures 27.57, 34.47 and 41.36 MPa, temperatures 40–70 °C and carbon dioxide flow rate between 1 and 3 ml/min. The effect of the particle size on the oil yield was examined using different particle size that separated by sieving from ⩽106, ⩽150, ⩽180, ⩽250 and ⩽450 μm. The results showed that the highest oil removed was 9.26 g oil/100 g sample (p < 0.05) for the particle ⩽150 μm, and under extraction temperature of 70 °C, pressure 41.36 MPa, and carbon dioxide flow rate of 2 ml/min. The experimental results indicate that supercritical carbon dioxide extraction could be a viable technique to remove the remaining oil and to produce defatted palm kernel cake.

Polyphosphates are important functional additives used in meats and other food products. They control the loss of natural juices, reduce susceptibility to freeze burn and cook losses by increasing water binding capacity of the products due to the increased pH and ionic strength. The objectives of this study were to investigate the phosphate diffusion in beef dipped in sodium tripolyphosphate solutions (STP) and to experimentally determine the fundamentals of the phosphate diffusion under these conditions. For this objective, the beef samples were dipped for 90 min in different concentrations of STPs (0%, 2%, 4%, and 6%, w/v) and analyzed for their phosphate content changes using a modified spectrophotometric ammonium molybdate method. The analysis was accomplished in both meat samples and solutions. Naturally occurred orthophosphates in meats and STPs in the solutions resulted in a counter-current diffusion. The phosphate content of the meats started to decrease to a certain time before showing an increase. On the contrary, phosphate content of the solutions regularly increased during dipping due to the diffusion of orthophosphates from the meat samples. Using these, the diffusion coefficient of STPs was determined for the different stages of dipping time. The results showed that the diffusion of phosphates may be analyzed using their phosphate content changes to determine the diffusion coefficient of STPs to accomplish further diffusion and optimization related research.

Water vapor adsorption of bulgur and hedik samples made from Triticum durum (Gediz 75) and Triticum aestivum (Panda) wheat were investigated. Experiments were conducted at 5, 15, 20, 30, and 40 °C for bulgur and at 20 °C for hedik samples between relative humidity (RH) of 11% and 100%. Bulgur samples became moldy before attaining equilibrium above 5 °C and 81% RH between 4 and 28 d depending on temperature (T). Hedik samples did not become apparently moldy and always had smaller equilibrium moisture content (X) than their bulgur counterparts at 20 °C and same RH. Type of wheat governed adsorption of the products. Bulgur and hedik of Gediz wheat always exhibited higher water adsorption capacity than bulgur and hedik of Panda wheat, respectively. The Guggenheim–Anderson–Boer model fitted all samples very well under the given conditions. The monolayer moisture content (Xm) was 9.7% and 9.6% (d.b.) for bulgur and hedik of Gediz wheat, and 7.5% and 6.5% (d.b.) for bulgur and hedik of Panda wheat, respectively. The heat of adsorption ( Q ) of bulgur samples was not affected by temperature and decreased with increasing X. Gediz bulgur had higher Q values than Panda bulgur up to the capillary condensation region. The average Q was obtained as 75, 50, and 45 kJ/mol for Gediz bulgur, and 73, 49, and 45 kJ/mol Panda bulgur for the monolayer, multilayer, and capillary adsorption regions, respectively.