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Formation of staling aldehydes in different grain bed layers in an industrial scale maltings


  • Weronika Filipowska KU Leuven
  • Irina Bolat Boortmalt
  • Gert De Rouck KU Leuven
  • Jeroen Bauwens KU Leuven
  • David Cook University of Nottingham
  • Luc De Cooman KU Leuven



staling aldehydes, bound state aldehydes, beer staling, pale malt, malting, industrial scale production, grain bed layers


Understanding the contribution of raw materials to the quality of the final product is crucial for the food industry. In the brewing process, malt delivers various compounds that compromise the flavour stability of beer, including staling aldehydes and their precursors. The primary aim of this study was to investigate the evolution of staling aldehydes and their cysteinylated counterparts throughout industrial scale pale malt production. The second objective was to study the extent to which process related gradients (e.g., temperature, moisture) may contribute to the differential formation of free and bound state aldehydes. Samples were collected from two industrial scale, pale lager malt production processes as a function of process time (germination, kilning, and cooling) and the position of the kernals in the grain bed (bottom, middle and top layers) during kilning. The levels of free and cysteinylated aldehydes were determined. The results show that the initial stage of germination is accompanied by enzymatic fatty acid oxidation as reflected by the formation of hexanal and trans-2-nonenal. Drying at elevated temperature (at a critical moisture content of 6-9%) results in the intensified formation of cysteinylated Strecker aldehydes and furfural. Moreover, a rapid increase in the formation of (cysteinylated) Strecker aldehydes furfural and trans-2-nonenal continued through kilning. A clear effect of temperature and moisture gradients was observed on the formation of aldehydes and it is concluded that exposure to heat load plays a critical role in the development of cysteinylated aldehydes during malt production.

This publication is dedicated to the memory of Professor Luc De Cooman.


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Amaya-Farfan J, Rodriguez-Amaya DB. 2021. The Maillard reactions. p 215-263 In Chemical Changes During Processing and Storage of Foods, Academic Press, London, UK. DOI:

Ames JM. 1990. Control of the Maillard reaction in food systems. Trends Food Sci Technol 1:150-154. DOI:

Andrés-Iglesias C, Nešpor J, Karabín M, Montero O, Blanco C A, Dostálek P. 2016. Comparison of carbonyl profiles from Czech and Spanish lagers: Traditional and modern technology. LWT 66:390-397. DOI:

Baert JJ, De Clippeleer J, Hughes PS, De Cooman L, Aerts G. 2012. On the origin of free and bound staling aldehydes in beer. J Agric Food Chem 60:11449-11472. DOI:

Baert JJ, De Clippeleer J, De Cooman L, Aerts G. 2015a. Exploring the binding behavior of beer staling aldehydes in model systems. J Am Soc Brew Chem 73:100-108. DOI:

Baert JJ, De Clippeleer J, Jaskula-Goiris B, Van Opstaele F, De Rouck G, Aerts G. 2015b. Further elucidation of beer flavor instability: the potential role of cysteine-bound aldehydes. J Am Soc Brew Chem 73:243-252. DOI:

Baillière J, Laureys D, Vermeir P, Van Opstaele F, De Rouck G, De Cooman L, Vanderputten D, De Clippeleer J. 2022. 10 unmalted alternative (pseudo)cereals: a comparative analysis of their characteristics relevant to the brewing process. J Cer Sci, 106:103482. DOI:

Bamforth C, Lentini A. 2011. The flavour instability of Beer p 85-109. In: Beer: A Quality Perspective. Handbook of Alcoholic Beverages. Academic Press, London, UK. DOI:

Barreiro JA, Fernández S, Sandoval AJ. 2003. Water sorption characteristics of six row barley malt (Hordeum vulgare). LWT 36:37-42. DOI:

Bathgate GN. 1983. The relationships between malt friability and wort viscosity. J Inst Brew 89:416-419. DOI:

Baxter ED. 1982. Lipoxidases in malting and mashing. J Inst Brew 88:390-396. DOI:

Baxter ED. 1984. Recognition of two lipases from barley and green malt. J Inst Brew 90:277-281. DOI:

Beal AD and Mottram DS. 1994. Compounds contributing to the characteristic aroma of malted barley. J Agric Food Chem. 42:2880-2884. DOI:

Belitz H, Grosch W, Schieberle P. 2009. Food Chemistry. Springer, Berlin, Germany. DOI:

Bravi E, Marconi O, Perretti G, Fantozzi P. 2012. Influence of barley variety and malting process on lipid content of malt. Food Chem 135:1112-1117. DOI:

Briggs DE. 1998. In Malts and Malting. Blackie Academic & Professional, London, UK.

Bustillo Trueba P, Jaskula-Goiris B, De Clippeleer J, Goiris K, Praet T, Sharma UK, Van der Eycken E, Sanders MG, Vincken JP, De Brabanter J, De Rouck G, Aerts G, De Cooman L. 2019. Validation of an ultra-high-performance liquid chromatography-mass spectrometry method for the quantification of cysteinylated aldehydes and application to malt and beer samples. J Chromatogr A 1604:460467. DOI:

Bustillo Trueba P. 2020. Beer flavour instability: unravelling formation and/or release of staling aldehydes. PhD Dissertation. KU Leuven, Ghent, Belgium.

Bustillo Trueba P, Jaskula-Goiris B, Ditrych M, Filipowska W, De Brabanter J, De Rouck G, Aerts G, De Cooman L, De Clippeleer J. 2021. Monitoring the evolution of free and cysteinylated aldehydes from malt to fresh and forced aged beer. Food Res Int 140: 110049. 9 DOI:

Coghe S, Benoot K, Basteyns A, Delvaux FR. 2004a. Influence of specialty malts on wort and beer characteristics. BrewSci 14:1-18.

Coghe S, Derdelinckx G, Delvaux FR. 2004b. Effect of non-enzymatic browning on flavor, colour and antioxidative activity of dark specialty malts – a review. BrewSci, 14:25-38.

Cortés Rodríguez N, Kunz T, Furukawa Suárez A, Hughes P, Methner F. 2010. Development and correlation between the organic radical concentration in different malt types and oxidative beer stability. J Am Soc Brew Chem 68:107-113. DOI:

De Clippeleer J, Van Opstaele F, Vercammen J, Francis G, De Cooman L, Aerts G. 2010a. Real-time profiling of volatile malt aldehydes using selected ion flow tube mass spectrometry. LC GC North America 28:386-395.

De Clippeleer J, De Rouck G, De Cooman L, Aerts G. 2010b. Influence of the hopping technology on the storage-induced appearance of staling aldehydes in beer. J Inst Brew 116:381-398. DOI:

De Clippeleer J. 2013. Flavour stability of pale lager beer. Chemical-analytical characterisation of critical factors related to wort production and hopping, PhD Dissertation. KU Leuven, Ghent, Belgium.

Derossi A, Severini C, Cassi D. 2011. Mass transfer mechanisms during dehydration of vegetable food: traditional and innovative approaches. In Adv Top Mass Trans 305-352. IntechOpen, London, UK.

Ditrych M, Filipowska W, De Rouck G, Jaskula-Goiris B, Aerts G, Andersen ML, De Cooman L. 2019. Investigating the evolution of free staling aldehydes throughout the wort production process. BrewSci 72:10–17.

Dong L, Piao Y, Zhang X, Zhao C, Hou Y, Shi Z. 2013. Analysis of volatile compounds from a malting process using headspace solid-phase micro-extraction and GC-MS. Food Res Int 51:783-789. DOI:

Ershov AY, Nasledov DG, Lagoda IV, Shamanin VV. 2014. Synthesis of 2-substituted (2R,4R)-3-(3-mercapto-propionyl)thiazolidine-4-carboxylic acids. Chem Heterocyc Comp 50:1032-1038. DOI:

Filipowska W, Jaskula-Goiris B, Ditrych M, Schlich J, De Rouck G, Aerts G, De Cooman L. 2020a. Determination of optimal sample preparation for aldehyde extraction from pale malts and their quantification via headspace solid-phase microextraction followed by gas chromatography and mass spectrometry. J Chromatogr A 1612:460647. DOI:

Filipowska W. 2020b. Identification of critical factors in malt production related to beer flavour (in)stability. Proc 36th IBD Congr. Perth, Australia.

Filipowska W, Jaskula-Goiris B, Ditrych M, Bustillo Trueba P, De Rouck G, Aerts G, Powell C, Cook D, De Cooman L. 2021. On the contribution of malt quality and the malting process to the formation of beer staling aldehydes: a review. J Inst Brew 127:107-126. DOI:

Gastl M, Spieleder E, Hermann M, Thiele F, Burberg F, Kogin A, Ikeda H, Back W, Narziss L 2006. The influence of malt quality and malting technology on the flavour stability of beer. BrewSci 163-175.

Guido LF, Boivin P, Benismail N, Gonçalves CR, Barros AA. 2005. An early development of the nonenal potential in the malting process. Eur Food Res Technol 220:200-206. DOI:

Guillén-Sans R, Guzmán-Chozas M. 1998. The thiobarbituric acid (TBA) reaction in foods: A review. Crit Rev Food Sci Nutr 38:315-350. DOI:

Hashimoto N. 1966. Report of the Research Laboratories of Kirin Brewery Co.

Hugues M, Bovin P, Gauillard F, Nicolas J, Thiry, J.-M., & Richard‐Forget, F. 1994. Two lipoxygenases from germinated barley‐heat and kilning stability. J Food Sci 59:885-889. DOI:

Jaskula-Goiris B, De Causmaecker B, De Rouck G, De Cooman L, Aerts G. 2011. Detailed multivariate modeling of beer staling in commercial pale lagers. BrewSci 64:119–139.

Jaskula-Goiris B, De Causmaecker B, De Rouck G, Aerts G, Paternoster A, Braet J, De Cooman L. 2019. Influence of transport and storage conditions on beer quality and flavour stability. J Inst Brew 125:60–68. DOI:

Kaukovirta-Norja A, Laasko S. 1993. Lipolytic and oxidative changes of barley lipids during malting and mashing. J Inst Brew 99:395-403. DOI:

Kunz T, Müller C, Mato-Gonzales D, Methner FJ. 2012. The influence of unmalted barley on the oxidative stability of wort and beer. J Inst Brew 118:32-39. DOI:

Lehnhardt F, Gastl M, Becker T. 2018. Forced into aging: Analytical prediction of the flavor-stability of lager beer. A review. Crit Rev Food Sci Nutr 2642-2653. DOI:

Lehnhardt F, Nobis A, Skornia A, Becker T, Gastl M. 2021. A comprehensive evaluation of flavor instability of beer (Part 1): Influence of release of bound state aldehydes. Foods 10(10):2432. DOI:

Lide DR. 2005. Handbook of Chemistry and Physics. CRC Press, Boca Raton, Finland.

Liedke R. 1999. Bildung von α-Dicarbonylverbindungen beim Abbau von Amadori- Umlagerungsprodukten. PhD Dissertation. Wilhelms-Universität Münster, Münster, Germany.

Lloyd WJW. 1988. Environmental effects on the biochemical phases of malt kilning. J Am Soc Brew Chem 46:8-13. DOI:

Malfliet S, Van Opstaele F, De Clippeleer J, Syryn E, Goiris K, De Cooman L, Aerts G. 2008. Flavour instability of pale lager beers: Determination of analytical markers in relation to sensory ageing. J Inst Brew 114:180-192. DOI:

Mallett J. 2014. From barley to malt. In Malt: A Practical Guide from Field to Brewhouse. Brewers publications, Brewers Association, Colorado, USA.

Mizuno A, Nomura Y, Iwata H. 2011. Sensitive measurement of thermal stress in beer and beer-like beverages utilizing the 2-thiobarbituric acid (TBA) reaction. J Am Soc Brew Chem, 69:220-226.

Müller C, Kleinwächter M, Selmar D, Methner FJ. 2014. The influence of elevated germination temperatures on the resulting malt quality and malting losses. BrewSci 67:18-25. DOI:

Nie C, Wang C, Zhou G, Dou F, Huang M. 2010. Effects of malting conditions on the amino acid compositions of final malt. Afr J Biotechnol 9:9018-9025.

Nobis A, Röhrig A, Hellwig M, Henle T, Becker T, Gastl M. 2019. Formation of 3-deoxyglucosone in the malting process. Food Chem 290:187-195. DOI:

Nobis A, Kwasnicki M, Lehnhardt F, Hellwig M, Henle T, Becker T, Gastl M. 2021. A comprehensive evaluation of flavor instability of beer (Part 2): the influence of de novo formation of aging aldehydes. Foods 10: 2668. DOI:

Nursten HE. 2005. The Maillard reaction – Chemistry, Biochemistry and Implications. The Royal Society of Chemists, London, UK.

Saison D, De Schutter DP, Uyttenhove B, Delvaux F, Delvaux FR. 2009. Contribution of staling compounds to the aged flavour of lager beer by studying their flavour thresholds. Food Chem 114:1206-1215. DOI:

Saison D, De Schutter DP, Vanbeneden N, Daenen L, Delvaux F, Delvaux FR. 2010 Decrease of aged beer aroma by the reducing activity of brewing yeast. J. Agric. Food Chem. 58: 3107–3115. DOI:

Svoboda Z, Mikulikova R, Belakova S, Benesova K, Marova I, Nesvadba Z. 2011. Optimization of modern analytical SPME and SPDE methods for determination of trans-2-nonenal in barley, malt and beer. Chromatographia 73:157-161. DOI:

Stadtma ER. 1993. Oxidation of free amino acids and amino acid residues in proteins by radiolysis and by metal-catalyzed reactions. Annu Rev Biochem 62:797-821. DOI:

Stephan A, Fritsch H, Stettner G. 2007. Influence of malt quality on the generation of odour active Strecker aldehydes during beer aging. Proceedings of the 31st Congress of the European Brewery Convention 99:1-4.

Thalacker R, Brikenstock BA. 1982. A new criterion in brewing analysis - the thiobarbituric acid number (TBN). Monatsschrift Fur Brauwissenschaft 35:133-137.

Vanderhaegen B, Neven H, Verachtert H, Derdelinckx G. 2006. The chemistry of beer aging - A critical review. Food Chem 95:357-381. DOI:

Vanderhaegen B, Delvaux F, Daenen L, Verachtert H, Delvaux FR 2007. Aging characteristics of different beer types. Food Chem 103:404-412. DOI:

Warmbier HC, Schnickels RA, Labuza TP. 1976. Effect of glycerol on nonenzymatic browning in a solid intermediate moisture model food system. J Food Sci 41:528-531. DOI:

Wietstock PC, Methner FJ. 2013. Formation of aldehydes by direct oxidative degradation of amino acids via hydroxyl and ethoxy radical at- tack in buffered model solutions. BrewSci 66:104-113.

Wietstock PC, Kunz T, Methner FJ. 2016. Relevance of oxygen for the formation of Strecker aldehydes during beer production and storage. J Agric Food Chem 64:8035-8044. DOI:

Wong CW, Wijayanti HB, Bhandari BR. 2015. Maillard reaction in limited moisture and low water activity environment p 41-63. In Water Stress in Biological, Chemical, Pharmaceutical and Food Systems. Springer, New York, US. DOI:

Yaylayan VA. 2007. Recent advances in the chemistry of Strecker degradation and Amadori rearrangement: implications to aroma and color formation. Food Sci Technol Res 9:1-6. DOI:




How to Cite

Filipowska , W., Bolat, I., De Rouck, G., Bauwens, J., Cook, D., & De Cooman, L. (2023). Formation of staling aldehydes in different grain bed layers in an industrial scale maltings . Journal of the Institute of Brewing, 129(4), 276–306.

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