STUDY OF THE DEVELOPMENT OF FREE AMINO NITROGEN DURING SORGHUM MALTING

Abstract

In the brewing process, barley malt is used as main raw material. Sorghumisone of themost suitable cereals to replacebarley becauseof itshigh nutritionalvalue.However,the sorghum beersupplyisstill insufficient in the global marketdue to the low qualityof its malt.The aim of this research was to study the development of free aminonitrogen (FAN) during sorghum malting forbrewing process by using Response SurfaceMethodology (RSM).ACentral Composite Rotatable Design (CCD) was used todevelop a statistical model for the optimization of process variables such as NaOHconcentration (0,2-0,5%(w/v)), steeping time (12-36 h), andgermination time (48-72 h).Data obtained from RSM on FAN production were subjected to the analysis ofvariance (ANOVA) and were analyzed using a second order polynomial equation.Optimum malting conditionsfor the highest FAN value(350,00 mg L-1) were:NaOHconcentration 0,35%, steeping time 26 h and germination time 63h.