According to World Guide to Beer, it was invented by Bavarian Monks about 500 years ago when they realized they could produce a clearer brew by storing it during the summer in wooden casks in cold caves.

• 根据《啤酒世界指南》一书，这种啤酒的酿造方法是大约500年前由巴伐利亚的和尚发明的。 他们认识到把酿造的酒在夏天贮存在木桶里，存放在冰冷的地窖里，这样就可以制造出更纯净的酒了。