Abstract—Rice used as adjunct is limited because the relative lower soluble nitrogen compare with that of barely will dilute total nitrogenous substances in wort and beer. Therefore, modification of mashing method and Neutrase^®; addition were proposed to increase rice/barley malt ratio. Total protein contents of four rice cultivars determined by Kjeldahl method were in a range of 6.53-7.49% (w/w). Amount of Neutrase® and mashing time for increasing protein were determined by mashing at 52 °C and found that increasing of mashing time increased soluble nitrogen and Free Alpha Amino Nitrogen (FAN) in wort more than 30% and 70%, respectively. The proper mashing time was 60 min and the appropriate amount of Neutrase^®; was 400 μl per 50 g rice. In addition, activation of Termamyl SC^®; at 95⁰C for 20 min also influenced more solubilized protein in rice cooking step. Afterward, the appropriate mashing program was evaluated in various rice/barley malt ratios. The qualified wort contained at least 150 mg/L FAN were obtained from wort used rice up to 80% and had satisfied fermentation performance. Therefore, Neutrase^®; addition plus modification mashing method could be one solution for increasing rice/barley malt ratio.

Index Terms—Mashing, protein, rice, wort.

P. Plainsrithong and U. Usansa are with the Department of Biotechnology, Kasetsart University, Bangkok, Thailand (e-mail:wa_waki@hotmail.com, fagiulw@ ku.ac.th ).
C. Wanapu is with the Department of Biotechnology, Suranaree University of Technology, Nakhonratchasima, Thailand (e-mail: wanapu@sut.ac.th).

 

Cite:Pailin Pliansrithong, Ulaiwan Usansa, and Chokchai Wanapu, "Increasing of Nitrogenous Substances in Wort by Using Commercial Enzymes and Modifying Mashing Method," International Journal of Bioscience, Biochemistry and Bioinformatics vol. 3, no. 4, pp. 404-407, 2013.