TY - JOUR
T1 - Optimization of malting conditions for two black rice varieties, black non-waxy rice and black waxy rice (Oryza sativa l. Indica)
AU - Usansa, Ulaiwan
AU - Burberg, Felix
AU - Geiger, Eberhard
AU - Back, Werner
AU - Wanapu, Chokchai
AU - Arendt, Elke K.
AU - Kreisz, Stefan
AU - Boonkerd, Nantakorn
AU - Teaumroong, Neung
AU - Zarnkow, Martin
PY - 2011
Y1 - 2011
N2 - Two black rice varieties, "black non-waxy" and "black waxy", were investigated as possible raw materials for the production of malt. The malting conditions were optimised using response surface methodology. The three process parameters were steeping, germination time and temperature. Each parameter was tested at three levels: adjustment degrees of steeping were 38, 41, and 44%, germination times were 6, 7, and 8 days, and the temperatures were 20, 25 and 30°C. At the end of the germination process, all samples were kilned at 50°C for 24 h, and shoot/rootlets were removed before a detailed quality assessment was performed. Data analysis was performed using the Design Expert Statistic Program. The optimal conditions found for both rice varieties were as follows: germination time of 8 days at 30°C and 44% grain moisture. Although the extract yield, and α-amylase and β-amylase activities of both rice malts were lower than barley malt, the higher activity of limit-dextrinase enzyme and apparent attenuation limit (AAL), which was higher than 80%, suggests that rice malt has potential for use in brewing.
AB - Two black rice varieties, "black non-waxy" and "black waxy", were investigated as possible raw materials for the production of malt. The malting conditions were optimised using response surface methodology. The three process parameters were steeping, germination time and temperature. Each parameter was tested at three levels: adjustment degrees of steeping were 38, 41, and 44%, germination times were 6, 7, and 8 days, and the temperatures were 20, 25 and 30°C. At the end of the germination process, all samples were kilned at 50°C for 24 h, and shoot/rootlets were removed before a detailed quality assessment was performed. Data analysis was performed using the Design Expert Statistic Program. The optimal conditions found for both rice varieties were as follows: germination time of 8 days at 30°C and 44% grain moisture. Although the extract yield, and α-amylase and β-amylase activities of both rice malts were lower than barley malt, the higher activity of limit-dextrinase enzyme and apparent attenuation limit (AAL), which was higher than 80%, suggests that rice malt has potential for use in brewing.
KW - Black rice
KW - Brewing
KW - Malting
KW - Response surface methodology (rsm)
UR - http://www.scopus.com/inward/record.url?scp=79956147591&partnerID=8YFLogxK
U2 - 10.1002/j.2050-0416.2011.tb00441.x
DO - 10.1002/j.2050-0416.2011.tb00441.x
M3 - Article
AN - SCOPUS:79956147591
SN - 0046-9750
VL - 117
SP - 39
EP - 46
JO - Journal of the Institute of Brewing
JF - Journal of the Institute of Brewing
IS - 1
ER -