Effect of Fermentation and Heat Treatment on the Nutrient and Antinutrient Composition of African Walnut (Tetracarpidium conophorum)
DOI:
https://doi.org/10.3923/pjn.2015.972.975Keywords:
Antinutrient, nutrient, Tetracarpidium conophorumAbstract
Conophor plant (Tetracarpidium conophorum) is a tropical climbing shrub that belongs to the family Euphorbiaceae. It is one of the lesser known and underutilized oilseeds. Mature conophor nuts were processed in three ways namely cooking for 2 h, roasting in hot sand at 130°C for 1 h and natural open air fermentation for three days. Both raw and processed samples were dried and milled into flour for the determination of proximate and mineral composition and certain antinutrients. The raw nuts showed high content of protein and fat. Cooking and fermentation further significantly (p<0.05) improved the protein level. Fat was significantly (p>0.05) reduced by fermentation. Ash, crude fibre and carbohydrates were significantly (p<0.05) reduced by the three processing methods. Fermentation significantly (p<0.05) reduced all the minerals determined. However, Ca content was significantly increased (p<0.05) by cooking and roasting. The sodium: potassium ratio in the raw sample (1.02) was reduced by the three processing methods. The level of antinutrients were generally reduced by cooking and fermentation with the latter being more effective than the former in the case of alkaloid content. Roasting increased the tannin content. The study thus reveals cooking and fermentation as good methods of processing the conophor nut in order to harness its nutrient.
References
Akeredolu, I.A., A.A. Addo and O.A. Akeredolu, 2005. Clinical evaluation of pearl millet conophor weaning mix as supplementary food for Nigerian children. Braz. Arch. Biol. Technol., 48: 531-536.
AOAC., 2000. Official Methods of Analysis. 15th Edn., Association of Official Analytical Chemists, Washington, DC.
Edem, D.O., E.S. Ekwere and O.U. Eke, 1994. Chemical evaluation of the effects of cooking on the nutritive value of Conophor seed (Tetracarpidium conophorum). Trop. Sci., 34: 377-380.
Egbe, I.A. and I.O. Akinyele, 1990. Effect of cooking on the antinutritional factors of lima beans (Phaseolus lunatus). Food Chem., 35: 81-87.
Ekwe, C.C. and A. Ihemeje, 2013. Evaluation of physiochemical properties and preservation of African walnut (Tetracarpidium conophorum). Afr. Res. Int., 4: 501-512.
Enujiugha, V.N., 2003. Chemical and functional characteristics of conophor nut. Pak. J. Nutr., 2: 335-338.
Enujiugha, V.N. and O. Ayodele-Oni, 2003. Evaluation of nutrients and some anti-nutrients in lesser-known, underutilized oilseeds. Int. J. Food Sci. Technol., 38: 525-528.
Harold, A. and D.P.I. Tatura, 2002. The Australian nutgrower. Aust Walnut Ind. Assoc., 49: 75-89.
Hudson, B.J.F. and E.A. El-Difrawi, 1979. Sapogenins of the seeds of four Lupin species. J. Plants Foods, 3: 181-186.
Lemann, Jr. J., 1999. Relationship between urinary calcium and net acid excretion as determined by dietary protein and potassium: A review. Nephron, 81: 18-25.
Nwokolo, E., 1987. Composition and availability of nutrients in some tropical grains and oilseeds. Nutr. Rep. Int., 36: 631-640.
Obizoba, I.C. and J.V. Atii, 1991. Effect of soaking, sprouting, fermentation and cooking on nutrient composition and some anti-nutritional factors of sorghum (Guinesia) seeds. Plant Foods Hum. Nutr., 41: 203-212.
Ogunsua, A.O. and M.B. Adebona, 1983. Chemical composition of Tetracarpidium conophorum (conophor nut). Food Chem., 10: 173-177.
Oke, O.L. and M.A. Fafunso, 1975. Lesser known oilseeds-the nutritive value of conophor seeds in vitro and rats. Nutr. Rep. Int., 12: 41-49.
Osagie, A.U., 1998. Antinutritional Factors. In: Nutritional Quality of Plant Foods, Osagie, A.U. and O.U. Eka (Eds.). Ambik Press, Benin, pp: 221-244.
Shamsa, F., H. Monsef, R. Ghamooshi and M. Verdian-Rizi, 2008. Spectrophotometric determination of total alkaloids in some Iranian medicinal plants. Thai. J. Pharm. Sci., 32: 17-20.
Tucker, K.L., M.T. Hannan, H. Chen, L.A. Cupples, P.W. Wilson and D.P. Kiel, 1999. Potassium, magnesium and fruit and vegetable intakes are associated with greater bone mineral density in elderly men and women. Am. J. Clin. Nutr., 69: 727-736.
Price, M.L., S. van Scoyoc and L.G. Butler, 1978. A critical evaluation of the vanillin reaction as an assay for tannin in sorghum grain. J. Agric. Food Chem., 26: 1214-1218.
Ukpabi, U.J. and J.I. Ejidoh, 1989. Effect of Deep Oil Frying on Oxalate Content and Degree of Itching of Cocoyam. In: Experimental Procedures for Food and Water Analysis, Odo, F.O. and C.N. Istiwu (Eds.). Computer Edge Publishers, London, pp: 84-88.
Wheeler, E.L. and R.E. Ferrel, 1971. A method for phytic acid determination in wheat and wheat fractions. Cereal Chem., 48: 312-320.
Downloads
Published
Issue
Section
License
Copyright (c) 2015 Asian Network for Scientific Information
This work is licensed under a Creative Commons Attribution 4.0 International License.
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.
