Acta Scientific Nutritional Health (ASNH)(ISSN: 2582-1423)

Research Article Volume 6 Issue 2

Amino Acids Analyses of Four Varieties of Raw and Cooked African Bitter Yam

Emmanuel Ilesanmi Adeyeye1*, Gbolagade Ayinde Yusuff2, Ayodele Olajide3, Idowu Olajumoke Tolulope4, Popoola Olugbenga Kayode1 and Idowu Kolade1

1Department of Chemistry, Faculty of Science, Ekiti State University, Ado-Ekiti, Nigeria
2Central Laboratory, Ekiti State University, Ado-Ekiti, Nigeria
3Department of Industrial Chemistry, Faculty of Science, Ekiti State University, Ado-Ekiti, Nigeria
4Chemistry Department, Afe Babalola University, Ado Ekiti, Ekiti State, Nigeria

*Corresponding Author: Emmanuel Ilesanmi Adeyeye, Department of Chemistry, Faculty of Science, Ekiti State University, Ado-Ekiti, Nigeria.

Received: December 10, 2021; Published: January 25, 2022


Background: Dioscorea dumetorum is a tuber that shows great variation in colour, form and quality.

Objective: The major purpose of this work is to report and compare the amino acid composition of both raw and cooked bitter yam.

Method: The D. dumetorum samples were the four edible different types available in Nigeria. For this work, the varieties were labelled as A6, B6, C6 and D6 (all raw samples), whereas A13, B13, C13 and D13 were the cooked equivalents. The method of amino acid analysis was by ion - exchange chromatography using the Technicon Sequential Multisample Amino Acid Analyser (TSM) (Technicon Instruments Corporation, New York, USA).

Results: For comparison, the raw and corresponding cooked samples had these total amino acid levels (in g 100g-1), A6/A13 (61.1/54.7), B6/B13 (65.1/54.7), C6/C13 (52.6/54.6) and D6/D13 (56.6/60.0). The amino acid values in the cooked samples showed both enhancement and leaching of the amino acids. EAA levels ranged from 25.5- 31.6g100g-1 in raw and 24.1- 26.0g100 g-1 in cooked samples. P-PER range was 1.63 - 2.88 (raw) and 1.59 - 2.43 (cooked). EAAI was 99.1 - 100 (raw) and 99.3 - 100 (cooked) whereas the BV values were 96.3 - 97.3 (raw) and 96.5 - 97.3 (cooked). The limiting amino acids were Ser, Met + Cys and Lys depending on the amino acid scoring standards compared to. Statistical comparisons among the pairs at r = 0.01 showed that significantly different: A6/A13, B6/B13, C6/C13 and D6/D13; A6/D6, A6/B6, A6/C6 and D6/C6; A13/B13, A13/C13, A13/D13, B13/C13 and D13/C13.

Conclusion: The EAAI, BV and P-PER showed the samples to be highly bioavailable. Samples A6 and B6 had generally similar chemical characteristics and slightly better food qualities than C6 and D6 which also showed similar chemical characteristics. The A13, B13, C13 and D13 were appendages of their corresponding A6, B6, C6 and D6 respectively.

Keywords: Dioscorea dumetorum; Bitter yam; Raw and Cooked compared, Amino acids, High biological value


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Citation: Emmanuel Ilesanmi Adeyeye., et al. “Amino Acids Analyses of Four Varieties of Raw and Cooked African Bitter Yam". Acta Scientific Nutritional Health 6.2 (2022): 39-53.


Copyright: © 2022 Emmanuel Ilesanmi Adeyeye., et al. 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.


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