Comparative study of physicochemical and thermal properties of the seed oils of three cucurbit species

Abstract

Three indigenous cucurbit seeds from Ivory Coast namely Cucumeropsis mannii Naudin, Citrullus lanatus var. Citroides (Thrumb.) Matsum & Nakai and Cucumis melo var. Agrestis were investigated for the physicochemical properties. Thermal properties of their crude oils extracted by a cold solvent method were also tested. Physicochemical characterization of the seeds showed that they are important sources of proteins, lipids, carbohydrates and mineral elements. C. lanatus seeds had the highest lipid content (46.40%) followed by C. melo seeds (36.50%) and C. mannii seeds (35.70%) on dry weigh bases. Most of the index values and chemical characteristics of extracted seed oils are not significantly different, except for the peroxide value and the color parameters of C. mannii. Linoleic acid, whose values ranged from 54.84% to 70.76%, was the major fatty acid out of all seed oil species. The thermal properties revealed that C. melo seed oil had low transition temperatures followed by C. lanatus seed oil and C. mannii seed oil depending on their fatty acid compositions. These results suggest that these thermal properties could be used in the industrial fractionation and the cucurbit seed oils may be used as edible oils due to their similarity to the commonly used edible oils.

Characterization of Acanthosicyos horridus and Citrullus lanatus seed oils: two melon seed oils from Namibia used in food and cosmetics applications

“…The peroxide values differed significantly among the oils of C. lanatus melon seed oil ranging from 1.69 to 2.98 mequiv/kg of oil with the MeTrd being significantly higher, whilst the peroxide value of the A. horridus melon seed oil ranged between 2.51 and 2.77 mequiv/kg, with no significant differences between the two extraction methods. Values observed for acid and peroxide values of C. lanatus and A. horridus melon seed oils are within the acceptable levels of the standards for edible oils of cold pressed origin (CODEX STAN 210-19992011, and are within reported values (2.3-9.8 mequiv/kg of oil) of melon seed oils (Mabaleha et al 2007;Gbogouri et al 2011;Nyam et al 2009;Mariod et al 2009). MeTrd was observed to have the highest p-anisidine value (1.69), and was significantly higher compared to MeCld and MeSox, but lower than the value (2.2) reported from melon seed oil from Botswana (Mabaleha et al 2007).…”

“…The iodine values of C. lanatus melon seed oil ranged from 110.28 to 118.61 g of I 2 /100 g of oil with the MeSox being significantly lower (110.28 g of I 2 /100 g of oil). Iodine values for Citrullus seed oils across Africa have been reported to range from 95.0 to 125 g of I 2 /100 g of oil (Mabaleha et al 2007;Gbogouri et al 2011;Nyam et al 2009;Mariod et al 2009). The iodine values for C. lanatus melon seed oil are compared to major edible oils, such as canola (110-126) oil, corn (107-128) oil, and sesame (104-120) oil (Gunstone et al 2007).…”

“…The specific gravity of C. lanatus melon seed oil ranged from 0.910 to 0.922, with the MeSox being significantly lower, whilst the specific gravity for A. horridus melon seed oil ranged between 0.881 and 0.921. Specific gravities of melon seed oils have been reported to range from 0.886 to 0.950 (Mabaleha et al 2007;Mariod et al 2009;Gbogouri et al 2011). The C. lanatus melon seed oil was observed to have refractive indices (1.4665-1.4720) which were significantly different among the three extraction methods investigated.…”

“…The dominant fatty acid in both oils was linoleic acid, an x-6 polyunsaturated fatty acid, in the range 52-57%. Linoleic as the dominant fatty acid is a characteristic property of melon seed oils (Mabaleha et al 2007;Gbogouri et al 2011;Mariod et al 2009). Linoleic acid, other than palmitic, oleic, and stearic acids, is not synthesized in the body.…”

Roasting Effect on the Nutritional and Cosmetic Potential of Citrullus Lanatus Kernels Oil

“…The abundance of lipids and proteins of dried kernels has already been demonstrated by Loukou et al (2007) and Gbogouri et al (2011) who also worked on the seeds of C. lanatus cultivated in Ivory Coast. Regarding the roasted kernels, these results could confirm that the roasting parameters (temperature: 250 °C; time: 20 min) used in this study are appropriate to preserve the wealth of C. lanatus kernels in these two compounds.…”