Hydrolytic Enzyme Levels in Malted Cereals

Abstract

Six grain samples namely barley, maize, millet, rice, sorghum and wheat were tested for enzyme levels (amylase, protease and lipase) in order to assess their malting characteristics, using barley as a standard. The levels of the enzymes were estimated in the whole dry grains, 24h steeped, 24h sprouted and 48h sprouted grains. A combined statistical analysis of linear regression and analysis of variance were used to test for enzyme interaction, similarities and interspecific relationship between the cereals. The estimated interspecific relationship between sorghum and barley was 84% based on the three enzymes, while millet had 75%. All the sprouted cereals with the exception of the standard barley had high lipase levels. This possibly suggests certain limitations as regards to production of off-flavours. Malt prepared from maize, sorghum, rice and millet had comparable protease levels with barley (P>0.05). The malts prepared from maize, millet, rice, sorghum and wheat had comparatively low alpha-amylase levels when compared with the standard barley. Multiple linear regressions showed amylase was dependent on lipase and protease. The relationship was not affected by either soaking (steeping) or sprouting of the grains. The implications of these findings suggest that a combination of these cereals might give good malt for food applications.

Optimisation of the production of corn amylase flour from corn Atp and Kassaï varieties for the fluidification and energy density increase of cassava gruel

“…Increasing the fluidity of the gruel with the germination time indicates a production of amylase-rich corn flour. Germination activates respiration, protein synthesis (amylase) and other metabolic activities ( Milala and Addy, 2014 ). These results are in accordance with those reported by Helland et al.…”

Effect of variety and malting conditions on proteolytic activity, free amino nitrogen, and soluble protein contents of two maize varieties (Atp-Y and Coca-sr): amylolytic activity and physico-chemical and functional properties of optimal sample

“…It follows from Figure 2 below that the FAN content of the Coca-sr variety increases gradually with salt concentration until it stabilizes at 1.6%, while that of the Atp-Y variety decreases with time. This could be explained by the different mechanisms of action of the proteases of the two varieties, the strong presence of inhibitors (Fe 2+ , Hg 2+ , Cu 2+ , and al 3+ ) of Atp-Y proteases in these salts as well as the compact molecular structure formed between proteins and polysaccharides at the level of the external layer of its wall ( 62 ). Furthermore, the removal of FANs by osmosis as a consequence of wall embrittlement would also explain this.…”

“…Senhofa et al ( 64 ) reported that hydrolysis of reserve proteins to release substrates and energy for embryo development would explain this. Activation of phytases and other anti-nutrient degrading enzymes leads to the release of soluble compounds including proteins ( 62 ). Inyang and Zakari ( 65 ) also reported an increase in protein content in sprouted cereals and vegetables.…”

“…43) also reported a variation in the optimal sprouting conditions of Nerica 3 and Nerica L56 rice seeds. They attributed this to a difference in epidermal composition, genetic variability, and a difference in enzyme localization zone in the two varieties (62).…”

A High-Throughput RNA Extraction for Sprouted Single-Seed Barley (Hordeum vulgare L.) Rich in Polysaccharides

“…In barley, an understanding of germination is highly emphasized because of its role in the economically important malting process. Germination and malt production involve dynamic changes to enzymatic activity, such as to the glucanases, amylases, and proteinases as physiological and chemical changes are made to the starchy endosperm [1,2,3,4,5,6]. Therefore, transcript expression analysis of these related genes can provide information about the level of activity in the germination process [7,8,9].…”