Tuber characteristics and nutrient composition of three morphotypes of Cyperus esculentus tubers and tuber oils were determined. The mean value for length and width of the tuber and one thousand dried tuber weights ranged from 0.98 to 1.31 cm, 0.90 to 1.19 cm, and 598 to 1044 g, respectively. Tubers displayed high level of starch (30.54–33.21 g 100 g−1), lipid (24.91–28.94 g 100 g−1), and sucrose (17.98–20.39 g 100 g−1). The yellow tubers had significantly higher content in lipid compared to black ones. Levels of ascorbic acid, tocopherol, and β-carotene of the three morphotypes differed significantly. Yellow ones (morphotypes 1 and 2) were the richest in tocopherol and the poorest in β-carotene. Saturated fatty acid content of morphotype 2 was significantly lower than that of morphotypes 1 and 3. Morphotype 3 had the significantly lowest PUFA content compared to morphotypes 1 and 2. Morphotype 1 was found to be richer in Ca, Cu, and Mn contents. Al, Mg, P, S, and Si were most abundant in morphotype 2. Morphotype 3 had the highest content of Cl, K, and Zn.

No abstract

No abstract

<em>Jatropha curcas</em> seed oil can be used for numerous purposes including fuel, soap and cosmetics. Better quality oil is obtained by cold pressing, the effectiveness of which is unfortunately limited by a low extraction rate. The objective of this study was to optimize cold hydraulic extraction parameters of <em>Jatropha curcas</em> seed oil by increasing the oil recovery and characterising the extracted oil. The key extraction parameters (dwell time, pressure, compression speed, and press cage charge) were determined using a laboratory hydraulic press. The results show that the unhulled and dehulled seeds contained 5.1 and 2.9% moisture, as well as 33.6 and 51.7% fat, respectively. Under the optimal operating conditions and at ambient temperature (25 °C), the oil recovery from whole (crushed) material was 38.2 (42.5)% unhulled seeds and 71.3 (69.5)% dehulled seeds. The physicochemical characteristics of cold-extracted Jatropha oil were 10ppm phosphorus, 1.9 ppm iron, 0.0 ppm copper, 0.15% water-volatile matter, 0.918 (15 °C) density, and 37.72 cSt (37.8 °C) kinematic viscosity, respectively. In conclusion, the optimized cold hydraulic extraction of jatropha seed oil leads to high oil recovery and good oil quality suitable for industrial applications.

No abstract