Drying kinetics and impact on the volatile compounds of ogi using response surface modelling

Abstract

This research aimed at studying the drying kinetic and impact on the volatile compounds of ogi slurry dried within designed drying condition (Drying temperature: 40, 50 and 60°C and drying time: 8, 10 and 12 hrs) using a central composite rotatable experimental design with two factors and five levels (-1.4142, -1, 0, 1 and 1.4142). Gas Chromatography-Mass Spectrometry (GC-MS) was used to detect volatile compounds of the dried ogi. The results revealed that the moisture content and moisture ratio of the samples decreased continually with the increase in drying temperature and time. The drying rate of the operation also decreased with increased drying time. The retention time of thirty-five volatile compounds detected in fresh ogi, dried ogi and dried maize grains ranged from 9.67 to 26.96 mins. There was a significant difference (p<0.05) between the concentration of volatile compounds detected in wet ogi compared with dried ogi. More than twenty volatile compounds identified in dried ogi and dried maize grains significantly (p<0.05) reduced up to 95-99% when compared with fresh wet ogi. The first and second principal components for dried ogi had variances of eigenvalue 32.04 and 1.92, respectively. The study revealed and established the challenges of retaining important volatile compounds responsible for aroma flavour in dried ogi product, most especially with the use of a cabinet dryer

Volatile Compounds Determination by GC-MS and Identification of Dominant Microorganism at Varying Fermentation Period of Ogi Slurry

“…. Similar results were reported for retention time of volatile compounds detected in dried ogi (Bolaji et al, 2020).…”