Effect of Conservation Methods on the Mineral Contents and the Nutritional Quality of the Oil of Some Maize Varieties (Zea mays L.) Produced in Côte d’Ivoire

Objective: The aim of this study was to evaluate the effect of conservation methods on the mineral
content of some maize varieties during post-harvest storage. To meet the needs for the human and
animal consumption, it is necessary to determine the mineral contents of raw materials.
Methodology: Eight maize varieties, including two local varieties used as controls (“Violet de Katiola”
and AC176) and six improved varieties (Obatanpa, MDJ, EV8728, GMRP18, Acr97TZLcomp-1w and
Acr97TZLcomp-1wsynth), produced by the Centre National de Recherché Agronomique (CNRA),
were stored according to three preservation methods (granary, attic and jute bag) during 120 days.
Sampling was performed every 30 days, followed by chemical analyses.
Results: The ash contents of local varieties were better preserved in the granary than in the attic or
the jute bag because no significant variation was observed at the end of the preservation time. In
improved varieties, all the ash contents varied. Concerning constitutive minerals, magnesium and
calcium contents were preserved in all varieties respectively during 30 and 120 days of storage in the
granary, the attic and the jute bag. On the other hand, some variations were observed for potassium
and phosphorus contents. For example, “Violet de Katiola” potassium content was best preserved in
the jute bag during 120 days; AC176 and EV8728 potassium contents were best preserved in the attic
respectively during 90 days and 60 days. The three preservation modes were suitable to maintain
ACr97 comp1wsynth potassium content between 60 and 120 days; but in this variety, phosphorus
was best preserved in the attic during 90 days. In level of nutritional quality of oil of the maize
varieties, the tenor of palmitic and linoleic acids of local varieties remained stable for 2 months in the
bag and 4 months in the attic, respectively, whereas the levels of oleic and linolenic acids remained
stable for 4 months in the canary. For improved varieties, palmitic and linoleic acid levels remained
stable for 2 months and 4 months respectively in the bag and oleic acid levels for 4 months in the attic
and canary. For For improved varieties, palmitic and linoleic acid levels remained stable for 2 months
and 4 months respectively in the bag and oleic acid levels for 4 months in the attic and canary.
Ultimately, the impact of duration and the method of conservation on the parameters of the corn grain
oils studied depends on the variety.
Conclusion: The three modes of maize grain storage were suitable to preserve magnesium and
calcium contents of local and improved varieties and Acr97TZLcomp1-wsynth potassium content.
Also, the impact of duration and the method of conservation on the parameters of the corn grain oils
studied depends on the variety