Kilning conditions for the optimization of enzyme levels in buckwheat

Buckwheat is a novel ingredient in malting and brewing, and therefore, requires optimization of the malting and brewing processes. In this study, three temperature regimens, 48 hr at 40°C (KR1), 5 hr at 40°C + 11 hr at 50°C (KR2), and 5 hr at 40°C + 3 hr at 50°C + 3 hr at 60°C (KR3) were used to kiln green buckwheat malt produced from grains steeped for 12 hr at 10°C and germinated for 96 hr at 15°C. Kilning regimens KR1, KR2, and KR3 produced malts with a moisture content of 6.8, 6.2, and 5.7%, respectively. Although an increased enzymatic activity level in buckwheat malt was noted with increased thermal exposure during the kilning regimen, it is not reflected in its brewing characteristics with regard to extract and apparent fermentability after using an optimized mashing system. However, the effect of treatment at higher temperatures with respect to enzymatic activity levels in buckwheat malt is reflected by rapid visco analysis where decreased peak viscosities correlate to an increased amylolytic activity level. The results of this study suggest that buckwheat, kilned using KR3, which was found to contain highest levels of amylolytic enzymes and produced the highest levels of total soluble nitrogen and free amino nitrogen when optimally mashed, be recommended for the kilning regimen of buckwheat green malt.