Gallardo Emerenciana, De Schutter David P, Zamora Rosario, Derdelinckx Guy, Delvaux Freddy R, Hidalgo Francisco J
Centre for Malting and Brewing Science, Katholieke Universiteit Leuven, Kasteelpark Arenberg 22, B-3001 Heverlee, Belgium.
J Agric Food Chem. 2008 May 14;56(9):3155-9. doi: 10.1021/jf800094k. Epub 2008 Apr 3.
The effect of lipids on the formation of the Strecker aldehyde phenylacetaldehyde during wort boiling was studied to determine the role that small changes in the lipid content of the wort have in the production of significant flavor compounds in beer. Wort was treated with 0-2.77 mmol per liter of glucose, linoleic acid, or 2,4-decadienal and heated at 60-98 degrees C for 1 h. After this time, the amount of the Strecker aldehyde phenylacetaldehyde increased in the samples treated with linoleic acid or decadienal but not in the samples treated with glucose. Thus, the amount of phenylacetaldehyde produced in the presence of linoleic acid was 1.1-2.5 times the amount of the Strecker aldehyde produced in the control wort, and this amount increased to 3.6-4.6 times when decadienal was employed. The higher reactivity of decadienal than linoleic acid for this reaction decreased with temperature and was related to the oxidation of linoleic acid that occurred to a higher extent at higher temperatures. The above results suggest that lipids can contribute to the formation of Strecker aldehydes during wort boiling and that changes in the lipid content of the wort will produce significant changes in the formation of Strecker aldehydes in addition to other well-known consequences in beer quality and yeast metabolism. On the other hand, because of the high glucose content in wort, small changes in its content are not expected to affect the amount of Strecker aldehydes produced.
研究了脂质对麦汁煮沸过程中Strecker醛苯乙醛形成的影响，以确定麦汁脂质含量的微小变化在啤酒重要风味化合物产生中所起的作用。用每升0 - 2.77毫摩尔的葡萄糖、亚油酸或2,4 - 癸二烯醛处理麦汁，并在60 - 98摄氏度下加热1小时。在此之后，用亚油酸或癸二烯醛处理的样品中Strecker醛苯乙醛的量增加，而用葡萄糖处理的样品中则没有增加。因此，在亚油酸存在下产生的苯乙醛量是对照麦汁中产生的Strecker醛量的1.1 - 2.5倍，当使用癸二烯醛时，这个量增加到3.6 - 4.6倍。癸二烯醛比亚油酸在该反应中的更高反应活性随温度降低，并且与亚油酸在较高温度下发生的更高程度的氧化有关。上述结果表明，脂质可在麦汁煮沸过程中促进Strecker醛的形成，并且麦汁脂质含量的变化除了对啤酒质量和酵母代谢产生其他众所周知的影响外，还将使Strecker醛的形成产生显著变化。另一方面，由于麦汁中葡萄糖含量高，预计其含量的微小变化不会影响产生的Strecker醛量。
