Effect of Amyloglucosidase on Wort Composition and Fermentable Carbohydrate Depletion in Sorghum Lager Beers

Abstract

A three-factorial experiment with a level of confidence of P < 0.05 was performed to study fermentable carbohydrate depletion and ethanol production during 144 h fermentations of lager beers produced with barley malt (BM), sorghum malt (SM), refined maize (MZ) or waxy sorghum (WXSOR) grits treated during mashing with or without amyloglucosidase (AMG). The percentage glucose, maltose and maltotriose, based on total fermentable carbohydrates for the BM wort was 20, 68 and 13% and for the SM wort 35, 48 and 17% respectively. Treatment with AMG increased wort glucose from 9.3 to 24.5 g/L wort and total fermentable sugar equivalents, expressed as g glucose /L, from 59.2 to 72.6 g/L wort. The SM worts had approximately 50% more glucose and 40% less initial maltose content respectively compared to the BM worts. The WXSOR grits produced worts and beers with similar properties to those produced from the MZ adjuncts. AMG addition led to a >2.5 fold increment in wort glucose and 23% in total fermentable carbohydrate content. Linear regression analysis determined that the consumption rate of fermentable carbohydrates during fermentation followed first order reaction kinetics. Depletion times to reach 50% of the initial concentrations of glucose, maltose and maltotriose were 49, 128 and 125 h, respectively, clearly indicating that the fermenting yeast preferred glucose. Maltose and maltotriose depletion times of the AMG treated worts were significantly faster and lower, respectively, when compared with the untreated worts. At the end of the fermentation, the BM beers contained higher ethanol levels (5.1% v/v) than the SM beers (3.9% v/v). For AMG treated beers, no significant differences in ethanol content were observed among samples mashed with BM and beers produced from SM and MZ grits. The results demonstrated that AMG could be used to increase the initial concentration of glucose and total fermentable carbohydrates thus decreasing dextrin levels, especially from sorghum mashes.

Addition of Sodium Stearoyl Lactylate to Corn and Sorghum Starch Extrudates Enhances the Performance of Pregelatinized Beer Adjuncts

“…On a per liter basis, total sugar yields obtained were higher than those reported by other authors who used 38% barley malt and corn grits (Del Pozo-Insfran et al 2004) and barley malt and sorghum grits in equal amounts (Espinoza-Ramírez et al 2013). On a per liter basis, total sugar yields obtained were higher than those reported by other authors who used 38% barley malt and corn grits (Del Pozo-Insfran et al 2004) and barley malt and sorghum grits in equal amounts (Espinoza-Ramírez et al 2013).…”

Use of Response Surface Methodology to Investigate the Effectiveness of Commercial Enzymes on Buckwheat Malt for Brewing Purposes

“…Fermentability and TFE appeared to approach limiting values which was expected. The addition of Amylo 300 increased >20% the amount of fermentable carbohydrate in sorghum malt, which is due to the degradation of dextrins into smaller fermentable carbohydrate moieties and complements intrinsic ␣-amylase activity by an amyglucosidase enzyme 2,19 . As expected, the addition of increasing levels of Amylo 300 to buckwheat mashes resulted in corresponding increases in fermentability and TFE, along with increases in TSN, FAN and KI.…”

“…It has been observed by many workers 2,3,19,23 that an increase in the total concentration of Amylo 300 results in a corresponding increase in fermentability. The results presented in Fig 2d support these findings.…”

“…The results presented in Fig 2d support these findings. Amylo 300 degrades dextrins into simpler fermentable carbohydrate moieties and complements intrinsic ␣-amylase acivity 19 .…”

Processing of a Top Fermented Beer Brewed from 100% Buckwheat Malt with Sensory and Analytical Characterisation

“…It must be noted however that an adjusted mashing regime was used in this study. Previous studies determined the effect of amyloglucosidase on the initial concentration of glucose and total fermentable carbohydrates in sorghum wort, and reported a >2.5 fold increment in wort glucose and 23% in total fermentable carbohydrate 3,55,61 . Current results do not support these findings when compared to optimally malted buckwheat mashed without the addition of amyloglucosidase 65 .…”