No abstract

In Côte d’Ivoire, maize plays an essential role as subsistence, commercial and socio-cultural culture. To consume good quality corn, it is necessary to preserve the sanitary quality through a good storage method. The aim of study was to evaluate sanitary quality of stored maize in triple bags containing plants biopesticides. Maize grains were collected in March 2016 in the north of Côte d’Ivoire. The fresh leaves of Lippia multiflora and Hyptis suaveolens were collected and dried in sunlight for 7 days in the center of Côte d'Ivoire. Triple bags were bought in Abidjan market. All this material was sent to the Laboratory of Biochemistry and Food Sciences, Félix Houphouët-Boigny University, Côte d’Ivoire, to perform the experiment. A central composite design was used for sample constitution. Ten treatments were obtained for the experimentation. The first treatment was conservation of 50 kg of maize grain in a polypropylene bag. The second treatment was conservation of 50 kg of maize grain in a triple bag. The other eight treatments were carried out with PICS bags each containing 50 kg of maize grain and different proportions of chopped leaves Lippia multiflora and Hyptis suaveolens. Thus, a control group with polypropylene bag (TPPB0), a control group in triple bag without biopesticides (TPB0) and 8 experimental lots of triple bags noted TB1 containing 0.625kg L. multiflora and 0.625kg H. suaveolens, TB2 with 0.40 kg of L. multiflora and 1.60 kg of H. suaveolens, TB3 with 1.60 kg of L. multiflora and 0.40 kg of H. suaveolens, TB4 with 0.10 kg of L. multiflora and 0.40 kg of H. suaveolens, TB5 with 0.40 kg of L. multiflora and 0.10 kg of H. suaveolens, TB6 with 2.5 kg of L. multiflora and 2.5 kg of H. suaveolens, TB7 with 1.25 kg of L. multiflora and TB8 with 1.25 kg of H. suaveolens have been used. The contents of moisture, water activity, aflatoxin B1 (AFB1), ochratoxin A (OTA), fuminosin B1 (FB1) and zearalenone (ZEA) were studied. The levels of AFB1, OTA, FB1 and ZEA resulted from maize grains treated with biopesticides were significantly lower than those recorded with untreated maize of control bags. The results show AFB1 levels (from 4.17 ± 0.05 to 5.15 ± 0.06 μg/kg), OTA levels (from to 4.58 ± 0.25 to 6.10 ± 0.01 μg/kg), FB1 levels (from 4.96 ± 0.07 μg/kg to 7.42 ± 0.06 μg/kg) and ZEA levels (from 4.66 ± 0.10 μg/kg to 8.78 ± 0.14 μg/kg). Maize samples stored in triple bagged bags with different proportions of biopesticide were significantly lower than those recorded in the polypropylene woven sample bag (TPPB0) and in the triple bagged control bag (TPB0) during the storage period. Storage of maize grains in triple bags with the leaves of L. multiflora and H. suaveolens appears as a method of effective and inexpensive conservation to ensure the sanitary quality of maize. This inexpensive and easy-to-use treatment should be popularized among farmers.

The aim of study was to evaluate merchantability quality of stored maize in triple bagging with biopesticides. Maize grains were collected in March 2016 in the north of Côte d’Ivoire. The fresh leaves of Lippia multiflora and Hyptis suaveolens were collected and dried in sunlight for 7 days in the center of Cote d'Ivoire. Triple bags were bought in Abidjan market. All this material was sent to the Laboratory of Biochemistry and Food Sciences, Félix Houphouët-Boigny University, Côte d’Ivoire, to perform the experiment. Ten treatments were obtained for the experimentation. The first treatment was conservation of 50 kg of maize grain in a polypropylene bag. The second treatment was conservation of 50 kg of maize grain in a PICS bag. The other eight treatments were carried out with PICS bags each containing 50 kg of maize grain and different proportions of chopped leaves Lippia multiflora and Hyptis suaveolens. A central composite design was used for sample constitution. Thus, a control group with polypropylene bags (TPPB0), a control group in PICS bags without biopesticides (TPB0) and 8 experimental lots of triple bags noted TB1 containing 0.625 kg L. multiflora and 0.625 kg H. suaveolens, TB2 with 0.40 kg of L. multiflora and 1.60 kg of H. suaveolens, TB3 with 1.60 kg of L. multiflora and 0.40 kg of H. suaveolens, TB4 with 0.10 kg of L. multiflora and 0.40 kg of H. suaveolens, TB5 with 0.40 kg of L. multiflora and 0.10 kg of H. suaveolens, TB6 with 2.5 kg of L. multiflora and 2.5 kg of H. suaveolens, TB7 with 1.25 kg of L. multiflora and TB8 with 1.25 kg of H. suaveolens have been used. Changes in moisture, damages and weight losses were studied. The results show moisture levels (from 09.02±0.11% to 12.07± 0.06%), weight loss (from 0.49±0.02% to 2.54±0.07%) and damage (from 0.99±0.02% to 3.96± 0.01%), corn stored in triple bagged bags with different proportions of biopesticide were significantly lower than those recorded in the Polypropylene woven sample bag (TPPB0) and in the triple bagged control bag during the storage period. The results obtained indicate stability in the quality of maize stored for 18 months in triple bagged bags containing different proportions of leaves of L. multiflora and H. suaveolens. A proportion of 5% of the mixture of leaves of L. multiflora and H. suaveolens (2.5 kg of L. multiflora and 2.5 kg of H. suaveolens) in triple bagged bags is recommended for a better preservation of the merchantability of the stored maize grains kernels. Storage of maize grains in PICS bags with the leaves of L. multiflora and H. suaveolens appears as a method of effective and inexpensive conservation to ensure the merchantability quality of maize.

Aims: Fungal pathogens are one of the main biological agents causing maize post-harvest loss and affect food security in the country. Thus, this study was conducted to assess fungal pathogens associated to post-harvest maize (Zea mays L.) with especial focus to mycotoxin-producing fungi at producer’s storage condition in different regions of Côte d’Ivoire. Study Design: A total of 1 500 samples of maize as grains, cobs and husks were collected at rate of 500 samples by region (Gbêkê, Poro, Hambol, Indénié-Djuablin and Gontougo) and sent to the laboratory in order to analyse their sanitary quality. Place and Duration of Study: This study was carried out during March 2016 to January 2017. The analyses of the collected sample carried out at the Biotechnology, Agriculture and Valorisation of Biological Resources Laboratory of the Félix Houphouët-Boigny’s University, Abidjan. Methodology: Microbiological analysis was assessed by recording the number of colony in the plate. The contents of aflatoxin and ochratoxin A in the different samples were determined using standard methods. Results: The total microbial species isolated ranged from 104 to 1011 cfu/g with thermotolerants coliforms (103 – 104) and fecal coliforms (102 – 103). The stored maize samples contained also high amount of yeast and molds (104 to 107 cfu/g). Aspergillus genus was the predominantly fungal isolated in all maize samples with tree species which are A. flavus, A. niger and A. versicolor potential producers of mycotoxins. More importantly, stored maize sample as grain, cobs and husks were affected by aflatoxins (B1, B2, G1 and G2) and ochratoxin A. Sixty per cent of the maize samples, mostly husks, showed aflatoxin B1 (from 12.73 to 130.31 µg/kg) and OTA (from 16.75 to 134.21 µg/kg) concentrations above the Maximum Authorized Limit of 5 µg/kg. Conclusion: A significant variability from one region to another can be noticed at level of maize quality regardless the type of maize. The sanitary quality of maize seems to be tied to postharvest treatments (drying), type of storage (grains, cobs and husks) and structure of storage.

In Côte d'Ivoire, inefficient storage Practices which can be dangerous to consumers' safety and to the environment are hampering the widespread availability of cereals, especially maize. Thus, a triple bagged system with or without plant biopesticides (Lippia multiflora and Hyptis suaveolens leaves) was used in this study to determine its effectiveness in preserving the hedonic sensory qualities of the grains for a period of 18 months under a 3-factor central composite design (CCD). The first CCD factor consisted of 6 observation periods: 0; 1; 4.5; 9.5; 14.5 and 18 months. The second factor was the type of treatment, which included a control lot with a polypropylene bag (NT) and 9 experimental lots, one of which was triple bagged without biopesticides (MGT1 and the other eight (8) lots containing varying proportions and/or combinations of biopesticides (MGT2 to MGT9). Finally, the third factor concerned the combination of the two biopesticides with the percentage (%) of Lippia multiflora as reference. Treated and stored maize kernels were periodically removed and processed into porridge for sensory analysis using a 9-point hedonic scale. The sensory parameters studied were color, taste, aroma, smell, mouthfeel and overall acceptability. The results showed that storage of maize grains in a triple bagging and biopesticide system for up to 18 months did not affect the hedonic sensory attributes studied. The porridges made from these grains were therefore judged pleasant by the panelists throughout the storage period. On the other hand, the porridges produced from grains stored in a polypropylene bag (NT) were considered unpalatable by the panelists after only 4.5 months of storage with respect to these sensory parameters evaluated. The results of the PCA and CAH analysis showed that the incorporation of at a minimum of 1.01% biopesticides (Lippia multiflora and Hyptis suaveolens leaves) in the triple bagging systems made the conservation better and maintained the organoleptic properties of the maize grains throughout the 18-month period.