Ran Qiu1,2,3, Jian Lu4,5,6. 1. The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, People's Republic of China. 2. National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, People's Republic of China. 3. School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, People's Republic of China. 4. The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, People's Republic of China. jlu@jiangnan.edu.cn. 5. National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, People's Republic of China. jlu@jiangnan.edu.cn. 6. School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, People's Republic of China. jlu@jiangnan.edu.cn.
Abstract
OBJECTIVES: Exogenous phytase improved the activity of hydrolases to decrease the malting time. RESULTS: Treatment with phytase during barley steeping increased activity of hydrolases (α-/β-amylase, proteinase, β-glucanase and xylanase) in green malt. Maximal activity was observed for α-/β-amylase, β-glucanase and xylanase with 0.8 U phytase/g and proteinase with 1.2 U phytase/g. Phytase promoted acrospire growth of green malt and reduced malting process with 0.8 U phytase/g in 96 h, which is 24 h less than the control. No significant variation of malt quality was found between control malt and malt treated with 0.8 U/g or 1.2 U phytase/g (P > 0.05), which makes application of exogenous phytase during steeping process as a good option for reducing malting time. CONCLUSION: Adding phytase during steeping process increases the activity of hydrolases, which reduces malting time without impacting on malt quality.
OBJECTIVES: Exogenous phytase improved the activity of hydrolases to decrease the malting time. RESULTS: Treatment with phytase during barley steeping increased activity of hydrolases (α-/β-amylase, proteinase, β-glucanase and xylanase) in green malt. Maximal activity was observed for α-/β-amylase, β-glucanase and xylanase with 0.8 U phytase/g and proteinase with 1.2 U phytase/g. Phytase promoted acrospire growth of green malt and reduced malting process with 0.8 U phytase/g in 96 h, which is 24 h less than the control. No significant variation of malt quality was found between control malt and malt treated with 0.8 U/g or 1.2 U phytase/g (P > 0.05), which makes application of exogenous phytase during steeping process as a good option for reducing malting time. CONCLUSION: Adding phytase during steeping process increases the activity of hydrolases, which reduces malting time without impacting on malt quality.