100%大麦啤酒酿造过程中老化Strecker醛的研究

Aging Strecker aldehydes in 100% barley beer brewing

分别采用上面发酵工艺与下面发酵工艺进行100%大麦啤酒及100%麦芽啤酒的酿制,并对其麦汁的氨基酸含量、老化Strecker醛、自由基以及新鲜啤酒中老化Strecker醛的含量等进行了对比分析。研究发现,就麦汁而言,100%大麦麦汁中老化Strecker醛的含量都明显低于100%麦芽麦汁;同样的麦汁,上面发酵方式还原Strecker醛的能力明显优于下面发酵方式。就啤酒而言,经酵母还原后,新鲜啤酒中的老化Strecker醛含量较麦汁含量低,且100%大麦啤酒中老化Strecker醛的含量低于100%麦芽啤酒中的含量。100%麦芽麦汁的自由基含量是100%大麦麦汁的近3倍。这都预示着100%大麦啤酒的风味稳定性(新鲜度)明显好于100%麦芽啤酒。

100% barley beer and 100% malt beer were brewed with top-fermentation and bottom-fermentation technology, respectively. The content of amino acids, aging Strecker aldehydes, free radicals in wort, as well as aging Strecker aldehydes content in fresh beers were analyzed. Results showed that in terms ofwort, the content of aging Strecker aldehydes was much lower in 100% barley wort than in 100% malt wort, and the ability of reducing Strecker aldehydes was obviously better with top-fermentation process than with bottom-fermentation process. It was also found that in terms of beer, the content of aging Strecker aldehydes in beers brewed with 100% barley was lower than those with 100% malt. The free radical level in 100% malt wort was nearly 3 times of that in 100% barley wort. All above results indicated that 100% barley beer has much better flavor stability （freshness） than 100% malt beer.