Oxidative reactions during early stages of beer brewing studied by electron spin resonance and spin trapping

被引:35
作者
Frederiksen, Anne M. [1 ,2 ]
Festersen, Rikke M. [2 ]
Andersen, Mogens L. [1 ]
机构
[1] Univ Copenhagen, Dept Food Sci, Frederiksberg, Denmark
[2] Novozymes AS, Bagsvaerd, Denmark
关键词
beer; sweet wort; electron spin resonance spectroscopy; oxidation; spin trapping; mashing;
D O I
10.1021/jf801666e
中图分类号
S [农业科学];
学科分类号
09 ;
摘要
An electron spin resonance (ESR)-based method was used for evaluating the levels of radical formation during mashing and in sweet wort. The method included the addition of 5% (v/v) ethanol together with the spin trap (alpha-4-pyridyl(1-oxide)-N-tert-butylnitrone (POBN) to wort, followed by monitoring the rate of formation of POBN spin adducts during aerobic heating of the wort. The presence of ethanol makes the spin trapping method more selective and sensitive for the detection of highly reactive radicals such as hydroxyl and alkoxyl radicals. Samples of wort that were collected during the early stages of the mashing process gave higher rates of spin adduct formation than wort samples collected during the later stages. The lower oxidative stability of the early wort samples was confirmed by measuring the rate of oxygen consumption during heating of the wort. The addition of Fe(II) to the wort samples increased the rate of spin adduct formation, whereas the addition of Fe(II) during the mashing had no effect on the oxidative stability of the wort samples. Analysis of the iron content in the sweet wort samples demonstrated that iron added during the mashing had no effect on the iron level in the wort. The moderate temperatures during the early steps of mashing allow the endogenous malt enzymes to be active. The potential antioxidative effects of different redox-active enzymes during mashing were tested by measuring the rate of spin adduct formation in samples of wort. Surprisingly, a high catalase dosage caused a significant, 20% reduction of the initial rate of radical formation, whereas superoxide dismutase had no effect on the oxidation rates. This suggests that hydrogen peroxide and superoxide are not the only intermediates that play a role in the oxidative reactions occurring during aerobic oxidation of sweet wort.
引用
收藏
页码:8514 / 8520
页数:7
相关论文
共 25 条
[1]   Electron spin resonance spin trapping identification of radicals formed during aerobic forced aging of beer [J].
Andersen, ML ;
Skibsted, LH .
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 1998, 46 (04) :1272-1275
[2]   Modification of the levels of polyphenols in wort and beer by addition of hexamethylenetetramine or sulfite during mashing [J].
Andersen, ML ;
Skibsted, LH .
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 2001, 49 (11) :5232-5237
[3]   Potential antioxidants in beer assessed by ESR spin trapping [J].
Andersen, ML ;
Outtrup, H ;
Skibsted, LH .
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 2000, 48 (08) :3106-3111
[4]   Oxidative degradation of lipids during mashing [J].
Arts, Mariken J. T. J. ;
Grun, Christoph ;
de Jong, Ruud L. ;
Voss, Hans-Peter ;
Bast, Aalt ;
Mueller, Martin J. ;
Haenen, Guido R. M. M. .
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 2007, 55 (17) :7010-7014
[5]  
BAMFORTH CW, 2004, MBAA TECH Q, V41, P97
[6]   What is responsible for the initiating chemistry of iron-mediated lipid peroxidation: An update [J].
Cheng, Zhiyong ;
Li, Yuanzong .
CHEMICAL REVIEWS, 2007, 107 (03) :748-766
[7]  
*EUR BREW CONV, 1998, EBC C MASH PROC EBC
[8]  
Franz O, 2002, MONATSSCHR BRAUWISS, V55, P156
[9]   Brewing performance of malted lipoxygenase-1 null barley and effect on the flavor stability of beer [J].
Hirota, N. ;
Kuroda, H. ;
Takoi, K. ;
Kaneko, T. ;
Kaneda, H. ;
Yoshida, I. ;
Takashio, M. ;
Ito, K. ;
Takeda, K. .
CEREAL CHEMISTRY, 2006, 83 (03) :250-254
[10]   Characterization of factors involved in the production of 2(E)-nonenal during mashing [J].
Kuroda, H ;
Furusho, S ;
Maeba, H ;
Takashio, M .
BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 2003, 67 (04) :691-697