Influence of Lipids in the Generation of Phenylacetaldehyde in Wort-Related Model Systems

• Published in: Journal of agricultural and food chemistry Vol. 56; no. 9; pp. 3155 - 3159
• Main Authors: Gallardo, Emerenciana, De Schutter, David P, Zamora, Rosario, Derdelinckx, Guy, Delvaux, Freddy R, Hidalgo, Francisco J
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 14.05.2008
• Subjects: Acetaldehyde - analogs & derivatives; Acetaldehyde - analysis; Acetaldehyde - chemistry; aldehydes; Aldehydes - chemistry; Beer - analysis; Beer quality; Beers; Biological and medical sciences; boiling; carbonyl−amine reactions; Chemical Changes Induced by Processing/Storage; decadienal; Edible Grain - chemistry; Fermented food industries; flavor compounds; Food industries; food processing; food processing quality; Fundamental and applied biological sciences. Psychology; glucose; Glucose - chemistry; Hot Temperature; linoleic acid; Linoleic Acid - chemistry; lipid content; lipid oxidation; Lipid Peroxidation; Lipids - analysis; Lipids - chemistry; Maillard reaction; phenylacetaldehyde; Strecker aldehydes; Taste; temperature; wort (brewing); wort boiling; Maillard reaction; Strecker aldehydes; lipid oxidation; carbonyl−amine reactions; wort boiling; Beer quality; Heat treatment; Lipids; Aldehyde; Boiling; Beer; carbonyl-amine reactions; Alcoholic beverage; Amine; Quality; Models; Oxidation
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf800094k

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 °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.