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elsewhere to be optimum at (Holcomb et al. 1992) 37 °C in the presence of other
favoring conditions (Smith et al. 2016).
12.9.2.2 Moisture Content
Water content is an important factor that affects both the grade and storability of
grains and legumes as it significantly influences microbial growth and toxin production. It is, thus, a key determinant of aflatoxin development in food crops. Storage
fungi like Aspergillus require about moisture of 13% or relative humidity of 65%
(water activity, a w , of 0.65) for growth and toxin production. However, 77% or above
is optimum for growth and proliferation. The researchers realized a significant (P¼
0.000) positive correlation between A. flavus population and aflatoxin production,
A. flavus population and water activity, and aflatoxin production and water activity
with respective correlation coefficients of 0.849, 0.75, and 0.68. Water activity is
however shown to increase with storage time; this coupled with improper drying
predisposes stored cereals and legumes to fungal infestation, growth, and aflatoxin
development (Okello et al. 2010).
12.9.2.3 Effect of Soil Properties on Aflatoxin Contamination in Food
Soil is another factor that has a key influence on fungal contamination in agricultural produce. Thus, crops cultivated in different soil types may have significantly
varying levels of aflatoxin prevalence. According to the Codex Alimentarius
Commission, light sandy soils accelerate growth of the fungi in peanuts, particularly under dry conditions, whereas heavier soils result in less contamination owing
to their high water retention capacity that helps in the reduction of drought stress.
Though Ghana is made of different soil types such as sandy, loamy, and clayey, the
specific type of soil of a particular area may depend on the part of the country it is
located. The northern part of the country has mainly sandy and sandy loamy soils,
while the southern part is made of soil types ranging from clayey loamy to dark
loamy (Fearon 2000; Braimoh and Vlek 2004; Abubakari 2012).
12.9.2.4 Impact of Nutrient Composition of Food
on Aflatoxin Contamination
Regardless of the fact that molds have the genetic potential to produce a particular
mycotoxin, the level and rate of production would partly be influenced by available
nutrients. As such, different food substrates may have different effects on aflatoxin
production due to the difference in nutrient content. Findings on the effect of nutrients in substrates (corn, wheat, peanut, soybean, corn germ, and corn endosperm)
on aflatoxin B1 production showed a slight A. flavus contamination and a relatively
low level of AFB1 in defatted substrates. However, AFB1 levels sharply increased
N. M. Abdelmotilib et al.
elsewhere to be optimum at (Holcomb et al. 1992) 37 °C in the presence of other
favoring conditions (Smith et al. 2016).
12.9.2.2 Moisture Content
Water content is an important factor that affects both the grade and storability of
grains and legumes as it significantly influences microbial growth and toxin production. It is, thus, a key determinant of aflatoxin development in food crops. Storage
fungi like Aspergillus require about moisture of 13% or relative humidity of 65%
(water activity, a w , of 0.65) for growth and toxin production. However, 77% or above
is optimum for growth and proliferation. The researchers realized a significant (P¼
0.000) positive correlation between A. flavus population and aflatoxin production,
A. flavus population and water activity, and aflatoxin production and water activity
with respective correlation coefficients of 0.849, 0.75, and 0.68. Water activity is
however shown to increase with storage time; this coupled with improper drying
predisposes stored cereals and legumes to fungal infestation, growth, and aflatoxin
development (Okello et al. 2010).
12.9.2.3 Effect of Soil Properties on Aflatoxin Contamination in Food
Soil is another factor that has a key influence on fungal contamination in agricultural produce. Thus, crops cultivated in different soil types may have significantly
varying levels of aflatoxin prevalence. According to the Codex Alimentarius
Commission, light sandy soils accelerate growth of the fungi in peanuts, particularly under dry conditions, whereas heavier soils result in less contamination owing
to their high water retention capacity that helps in the reduction of drought stress.
Though Ghana is made of different soil types such as sandy, loamy, and clayey, the
specific type of soil of a particular area may depend on the part of the country it is
located. The northern part of the country has mainly sandy and sandy loamy soils,
while the southern part is made of soil types ranging from clayey loamy to dark
loamy (Fearon 2000; Braimoh and Vlek 2004; Abubakari 2012).
12.9.2.4 Impact of Nutrient Composition of Food
on Aflatoxin Contamination
Regardless of the fact that molds have the genetic potential to produce a particular
mycotoxin, the level and rate of production would partly be influenced by available
nutrients. As such, different food substrates may have different effects on aflatoxin
production due to the difference in nutrient content. Findings on the effect of nutrients in substrates (corn, wheat, peanut, soybean, corn germ, and corn endosperm)
on aflatoxin B1 production showed a slight A. flavus contamination and a relatively
low level of AFB1 in defatted substrates. However, AFB1 levels sharply increased
N. M. Abdelmotilib et al.