Current Developments in Malting and Brewing Trials with Sorghum in Nigeria: A Review

Initially, large-scale lager beer brewing with sorghum malts proved highly intractable due to a number of biochemical problems including: high malting losses estimated at 10–30% as against 8–10% for barley; high gelatinisation temperatures which limited starch solubilisation/ hydrolysis by the amylolytic enzymes during mashing; low extract yield/low diastatic power (DP) due to inadequate hydrolytic enzyme activities especially β-amylase; low free α-amino nitrogen (FAN) due to inadequate proteolysis limiting yeast growth during fermentation; high wort viscosities/beer filtration problems due to low endo-β-1,3; 1–4-glucanase activities on the endosperm cell walls causing the release of some β-glucans. Strident research efforts using improved Nigerian sorghum malt varieties (SK5912, KSV8 and ICSV400) have reported some encouraging results. The knowledge of the biochemical integrity of the endo-β-glucanases of the sorghum malt is helping to elucidate their mode of activity in the depolymerisation of the β-glucans. This is bound to ensure process efficiency in sorghum beer brewing, reduce beer production costs and ultimately, produce a Pilsner-type of lager beer with 100% sorghum malt.