Nutritive Compounds of Traditional Rainfed Rice (Oryza glaberrima) from Goh-Djiboua and Mountains Districts in Côte d’Ivoire

Abstract

Aims: The biochemical composition of rainfed rice (Oryza glaberrima) consumed in Côte d'Ivoire has not yet been revealed, whereas rice is of the main staple foods for many people. This work investigates the main biochemical traits of numerous traditional rainfed rice varieties from Ivorian environment, namely in Gôh-Djiboua and Mountains Districts, for better valorization. Study Design:  Study performed on traditional rainfed rice varieties collected from 450 farmers in both regional Districts mentioned above. Shelled rice perceived per variety, conditioned, and total final 5.4 kg of resulted rice considered, 200g per variety, for due laboratory investigation. Place and Duration of Study: Sampling between January and June 2017, full analysis by 2018 in Laboratory of Food Sciences, Felix Houphouët- Boigny University. Methodology: All rice samples conveyed to laboratory, then 100g taken per variety, oven-dried at 50 °C/72 h, ground in metallic grinder, sealed into polyethylene bags, and kept into desiccator till analyses. Investigations consisted in triplicate evaluation of moisture, carbohydrates (total glucides, starch, soluble carbohydrates, reducing carbohydrates), fats, proteins, caloric energy, fibres, and ash by rice sample. Results: Great variability (P<.001) recorded between rive samples for biochemical traits assessed. Thus, the variety Jbröko represents the most important source of glucides (84.19±0.37g/ 100 g) and caloric energy (322.17±0.37kcal/ 100 g) compared to the other varieties. Oppositely, the variety Yoroukouiagnêzê recorded the highest proteins content (7.27±0.03 g/100g), whereas Abê provides more food fibres (6.67±0.14g/ 100g). Otherwise, the variety Danané belating is richer in free soluble sugars (4.63±0.08 g/100 g), while Azi red displayed more moisture content (10.96±0.1%) and Gbêklêazi is richer in lipids with content of 1.26±0.21g/ 100g. The top ash and starch contents were respectively recovered from varieties Zonhonkloumin black (1.38±0.02 g/100 g) and Abê (71.99±0.03g/ 100g). Conclusion: The studied rainfed rice record good nutritive traits above the widespread improved rice varieties. They remain significant caloric food resources thanks to considerable contents in glucides (varieties Abê, Akita, Jbröko, No-No-No, and Danané I), proteins, lipids, and significant amount of food fibre (varieties Boumabou, Glawlon, Dikouè, Loêgnini, and Danané fowl) and minerals. This nutritive composition could permit their quite usages for consumers and researchers, even though other investigations on the functional nutritional compounds should be performed.