Proximate Composition and Antinutrient Contents of Some Common Spices in Nigeria

ABSTRACT

Indigenous Nigerian spices consist of parts of trees, shrubs and grass which abound in the tropical rain forest and savannah grassland zones. They are used principally to spice foods and drinks and as medication for various ailments. Although they are important components of the diets of rural Nigerians, knowledge of their contributions to human nutrition and contents of toxicants that influence the availability of nutrients in foods is lacking and has limited their use in food. The proximate composition and contents of naturally occurring toxicants (antinutrients) of five commonly consumed Nigerian spices: ‘bafilo’ (Uapaca guineense), ‘atarko’ (Zanthoxyllus zanthoxyloides). ‘amilo’ (Parinari excelsa), ‘uburo’ (Afromomum danielli) and ‘clove’ (Syzygium aromaticum) were evaluated and studied. The protein, carbohydrate and lipid contents of U. guineense, Z. zanthoxyloides, P. excelsa, A. danielli and S. aromaticum ranged from 7.8 – 8.6%, 67.6 – 68.6% and 9.3 – 10.8%, respectively while their ash contents ranged from 1.1 - 1.7%. U. guineense, Z. zanthoxyloides, S. aromaticum had highest protein, lipid and carbohydrate contents respectively while U. guineense had a significantly (P ≥ 0.05) higher total ash than other spices analysed. The cyanogenic glycoside, oxalates, tannins, saponins and phytate contents of raw U. guineense, Z. zanthoxyloides, P. excelsa, A. danielli and S. aromaticum ranged from 3.4 – 10.2mg /100g, 0.6 – 3.1mg/100g, 0.6 – 5.0mg/100g, 2.6 – 6.4mg/100g and 2.8 – 4.8mg/100g respectively. Generally, the antinutrient contents of the market samples were low and below stated levels of toxicity. Boiling and dehulling of seeds prior to pulverising and packing of spices caused significant (P ≥ 0.05) reductions in the antinutrient contents of the processed spices. Mean reductions of 71.5%, 87.5%, 73.1%, 71.9% and 73.9% cyanogenic glycosides, oxalates, polyphenols, saponins and phytates in U. guineense, Z. zanthoxyloides, P. excelsa, A. danielli and S. aromaticum respectively were obtained in the processed spices. The implications of these treatments on the contents of toxicants in foods are also discussed.

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