Impact of Wheat Flour Infestation by some Insects on its Quantity and Quality Loss, Fungal Contamination and Mycotoxins

Abstract

Wheat flour samples were artificially infested with Corcyra cephalonica, Ephestia kuehniella, Tribolium confusum (separately) and with the three insect populations together. The effect of insects' infestation on wheat flour quantity and quality loss, fungal contamination and presence of mycotoxins was studied after two months of storage (25±2 o C and 65%RH). Wheat flour infested with insects was sieved into two portions (sieved and residual flour) after insects populations have been recorded. The results revealed radical changes in weight loss, population density of insects, nutritional composition, interaction between insects and fungal contamination in the flour samples. The maximum residual flour loss was recorded by C. ceplalonica followed by E. kuehniella while the minimum residual loss was induced by T. confusum. The flour consumption by the tested insects may be arranged in descending order as follows: three insects tested together > C. cephalonica > T. confusum > E. kuehniella. There was a significant correlation between the amount of flour consumed and insect population. Also, there was a significant increase in the total protein contents and decrease in the monosaccharaides and disaccharides in all infested sieved and residual flour samples tested. The average log total molds count in control flour samples was 1.28, while the average log of insect infested flour samples ranged from 2.36 to 4.34. Seven to ten fungal species belonging to five genera (Aspergillus, Penicillium, Cladosporium, Eurotium and Emercilla) were isolated from control and infested flour samples. Many fungal species were isolated from infested flour, but most of them belong to Aspergillus and Penicillium. Aflatoxins B1, B2 were detected in all flour samples, but at different levels. Ochratoxin A was not detected in the control samples and C. cephalonica flour samples while it was detected in flour samples infested with the other treatment.

Effect of feeding rats on gamma irradiated flour infected with Tribolium confusum

“…These agreed with that obtained by Ahmadi et al (21) who found that gamma radiation significantly affect the nutritional indices of T. castaneum. Moreover, Gabarty and Abou El Nour (22) studied the effect of artificially infestation of 3KGy irradiated flour with Corcyra cephalonica, Ephestia kuehniella, T. confusum, they declared that there were major alterations in the insects population and high weight loss and lowering of the nutritional composition of the flour.…”

Insect as major carrier of aflatoxins and mycotoxin in foods: A review

“…The level of AB 1 and AB 2 were checked all in wheat flour samples. These findings documented the role of insects in infestation of wheat flour through aflatoxigenic fungi in storage system (Gabarty & El Nour, 2016) [19] . Insects, fungi and aflatoxin contamination are previously discussed in detailed in maize plant.…”

Hermetic Bags Help Afghan Rural Women Preserve Wheat Flour during Winter

“…The wheat flour stored in PP bags was infested by T. castaneum, and the population increased with storage time. Tribolium castaneum is well known as a pest of wheat flour stocks [ 10 , 13 , 20 ]. The development of insects in PP bags was due to favorable environmental conditions such as high humidity [ 21 , 22 ].…”

“…Through its feeding activities, T. castaneum affects the quality of the wheat flour, including fatty acids, proteins, and gluten. The presence of T. castaneum can also result in the development of toxins such as benzoquinones and aflatoxins [ 13 , 20 ]. In addition, parts of dead insects can affect the quality of the wheat flour by increasing its water content, microbial fauna, and uric acid content, as well as changing the color of the flour [ 23 ].…”