Advances in Food Science and Technology

Advances in Food Science and Technology ISSN: 6732-4215 Vol. 8 (4), pp. 001-013, April, 2020. © International Scholars Journals

Full Length Research paper

Natural occurrence of AFB1 in maize and effect of traditional maize flour production on AFB1 reduction in Malawi

L. Matumba¹, M. Monjerezi²*, E. Chirwa³, D. Lakudzala⁴ and P. Mumba⁵

¹Chitedze Agricultural Research Station, P. O. Box 158, Lilongwe, Malawi.

²University of Malawi, Chemistry Department, Chancellor College, P. O. Box 280, Zomba, Malawi.

³University of Malawi, Department of Mathematical Sciences, Chancellor College, P. O. Box 280, Zomba, Malawi.

⁴University of Malawi, Department of Physical and Biochemical Sciences, The Malawi Polytechnic, P/bag 303, Chichiri, Blantrye 3, Malawi.

⁵University of Malawi, Department of Basic Sciences, Bunda College of Agriculture, P. O. Box 219, Lilongwe, Malawi.

Accepted 12 November, 2019

Abstract

Aflatoxin B₁ (AFB₁) is one of the most harmful mycotoxins to humans, animals, and crops that result in illnesses and economic losses. Maize, the most important staple food in most southern African countries, is susceptible to these fungi infections throughout its growth, harvest, transport and storage. In this study, we report on the incidence of AFB₁ (determined by indirect competitive ELISA) contamination in maize from Malawi and the effect of traditional maize- flour production procedures on the final AFB₁ levels. AFB ₁ was detected in 45.3% of the maize samples with 12.3% of them exceeding 5 µg/kg (FAO median AFB ₁ MTL). The traditional flour production procedures reduced AFB ₁ significantly in the order: soaking of dehulled maize (72.4±5.4, 75.4±3.5 and 80.9±5.3% for 24, 48 and 72 h soaking periods, respectively) > dehulling of maize (mean 29.3±5.4%) > sun drying (11.7% max). Sun drying followed pseudo-first order kinetics in AFB₁. A maximum AFB ₁ reduction of 88.1 ± 3.1% was achieved using a sequence of dehulling, soaking for 72 h and sun drying the flour for 4.5 h.