A new eco-friendly defatting process of peanuts by mechanical expression preserving structure integrity (MEPSI)
This article represents a scientific approach to the environment-friendly and energy saving processes which incited us to develop a new efficient, healthy, economical and less polluting defatting process. In this paper, mechanical oil extraction was conducted on peanuts by preserving their structure integrity and the process was followed by a quantitative and qualitative study on the physicochemical properties of the defatted grains in order to investigate the best extraction parameters. The described extraction process coupled to a reconstitution process by Intensification of Vaporization by Decompression to the Vacuum (IVDV) showed that the optimal conditions are 5% d.b. initial water content, 2 days at 4°C of homogenization period, pressing at around 10 MPa (at room temperature) for 3 to 4 min most preferably at a compression speed of 8mm/sec, using the appropriate process modification to avoid structure damages and loss of deteriorated seeds, then reconstituting by IVDV with a pressure of 0.9MPa applied for 10 sec on hydrated peanuts to 10% d.b.
Gas assisted mechanical expression of cocoa butter from cocoa nibs and edible oils from oilseeds
The current methods used to recover high quality oil from oilseeds have low yields (mechanical expression, aqueous extraction), require the use of toxic chemicals and rigorous purification processes that can reduce the quality of the oil (solvent extraction with hexane) or are unsuitable for the recovery of commodity oils due to the low solubility of plant oils in environmentally benign solvents (supercritical extraction with CO2). Gas assisted mechanical expression (GAME) utilises the much higher solubility of supercritical CO2 in the oil to enhance the extraction yields of mechanical expression. GAME experiments with cocoa nibs were performed at 40–100 °C, CO2 pressures of 0–20 MPa and effective mechanical pressures of 20–50 MPa. The maximum yield with conventional expression (71.8%) was obtained at a mechanical pressure of 50 MPa and a temperature of 100 °C. It is shown that GAME has a substantially higher yield than conventional mechanical expression for the recovery of cocoa butter from cocoa nibs, with the highest yield (87.1%) obtained at 100 °C, a CO2 pressure of 10 MPa and an effective mechanical pressure of 50 MPa. The cocoa butter yield increases with increasing CO2 pressure until 10 MPa but remains almost constant for higher CO2 pressures. In contrast to conventional expression GAME also allows the recovery of cocoa butter from cocoa nibs at temperatures below the melting point of pure cocoa butter. The cocoa butter produced with GAME was found to be unfractionated and is therefore of the same quality as mechanically expressed cocoa butter. Experiments with linseed and sesame seed show that GAME performed at 40 °C with 10 MPa CO2 also results in an increased yield of oil (71.8–83.8% for linseed, 74.3–80.2% for sesame seed) when compared to the yield obtained with conventional mechanical expression performed at 40 °C (38.5–45.7% for linseed, 60.1–65.6% for sesame seed). From these results it is concluded that GAME offers a promising process for the recovery of high-quality vegetable oils at high yields.
Pharmacokinetics of amikacin and chloramphenicol in the aqueous humor of rabbits
Composite data describing ocular pharmacokinetics are unreliable because of intersubject variation. To address this problem, an animal model was developed in which multiple aqueous samples from single subjects were obtained. Following direct anterior chamber or intravenous administration of amikacin or chloramphenicol, pharmacokinetic analysis of drug concentrations in the serum and anterior chamber was performed by using a nonlinear least-squares regression program. The number of anterior chamber paracenteses performed did not alter the beta elimination rates or percent penetration into the anterior chamber. The aqueous humor and peripheral-compartment terminal slopes were identical. These data indicate that complete ocular concentration-time curves can be obtained without altering antibiotic pharmacokinetics. Following direct injection into the anterior chamber, the elimination rates for both antibiotics followed a one-compartment model, whereas those following intravenous administration best fit an open, first-order, two-compartment model. Following intravenous administration, the anterior chamber elimination rate constants for both drugs were equal to that of the serum and significantly longer than that following direct injection. The elimination rates of both drugs following direct injection were similar. Systemic administration resulted in drug levels in aqueous humor that persisted longer than those following direct injection. Chloramphenicol, a lipophilic compound, gave higher mean concentrations in aqueous humor than did amikacin. Our model provides a new approach which rigorously examines ocular pharmacokinetics and provides data which suggest that for selected compounds the parenteral route of administration is preferable.