Effect of processing methods on the nutritional composition and sensory properties of two African mango (Irvingia gabonensis) seed varieties

Abstract

The objective of this study was to determine effects of processing methods on the nutritional composition and sensory properties of two African mango (Irvingia gabonensis) seed varieties- Irvangia gabonensis var. gabonensis and Irvingia gabonensis var. wombolu. Four processing methods (boiling, soaking, blanching and defatting) were used to treat the samples. The treated and untreated African mango locally called ‘ogbono’ in Nigeria were processed into flours, and used to prepare soups, and results analyzed. Proximate, viscosity and sensory properties of the soups were determined, as well as the proximate, mineral and phytochemical contents of the flours. The moisture, ash and crude fibre content of the flours ranged from 6.20-8.91%, 1.25-1.98% and 1.10-1.70%, respectively. The mineral content of the flours ranged from 262.79-801.25 mg/100g for calcium, 1.48-6.90 mg/100g for iron, 255.13-754.24 mg/100g for sodium and 173.14-285.69 mg/100g for magnesium. Results revealed that the various treatment methods reduced the phytochemical contents of the treated flours. Hydrogen cyanide content of the untreated flours ranged from 3.66-4.06 mg/kg as against the treated samples which ranged from 2.23-3.76 mg/kg. The sensory properties of the soups were evaluated. Sample A0 recorded the highest (7.61) for taste, 7.50 for thickness, and overall acceptability of 7.48. The highest sensory score for drawability was recorded by sample A2 with 7.45, while sample B4 had the lowest sensory score (2.40) for drawability. Sample B4 also recorded the least sensory score for thickness (2.65), while the least score for appearance (3.40) and overall acceptability (3.76) was recorded in sample A4. Sample A2 had the highest viscosity (76.71 Pa.s) while sample B4 recorded the least viscosity (19.63 Pa.s). This study reveals that processing methods like boiling, soaking, blanching and defatting on the seeds improved the proximate and mineral compositions of the flours, reduced the phytochemical contents of the flours and maintained the drawability of the soups prepared with the two varieties.