Measurement of malonaldehyde in apple juice using
GC–MS and a comparison to the thiobarbituric acid assay
Xuetong Fan*
US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center,
600 E. Mermaid Lane, Wyndmoor, PA 19038, USA
Received 21 August 2001; received in revised form 17 December 2001; accepted 17 December 2001
Abstract
Malonaldehyde (MA) in gamma-irradiated apple juice was measured using a GC–MS method and in comparison to the thio-
barbituric acid (TBA) assay. The profiles of MA content as a function of radiation dose were similar using both methods, however,
MA content was higher when measured with the TBA assay compared to the GC–MS method. The overestimation of MA using the
TBA assay increased as the amount of MA decreased. Use of the GC–MS method demonstrated MA content in irradiated juice declined
rapidly during storage at 5
C. MA content appeared to decrease much less when the TBA assay was used. The GC–MS method
also allowed measurement of formaldehyde and acetaldehyde in addition to MA. Published by Elsevier Science Ltd.
Keywords: GC–MS; Irradiation; Juice; Malonaldehyde; Thiobarbituric acid assay
1. Introduction
Malonaldehyde (MA) has been extensively studied in
biological and medical sciences due to its reactivity with
biological macromolecules and possible connection to
cancer and other diseases (Janero, 1990). MA is also
widely applied as an index of lipid oxidation and ran-
cidity of various foods, especially meats and meat pro-
ducts (Guillen-Sans & Guzman-Chozas, 1998; Raharjo
& Sofos, 1993). The traditional method for MA deter-
mination has been the thiobarbituric acid (TBA) assay
owing to its simplicity. In this method, MA reacts with
TBA via an acid-catalyzed nucleophilic-addition reac-
tion yielding a pinkish-red chromophore with an absor-
bance maximum at 532 nm. However, TBA is not
specific to MA, and many other compounds may give
colored products that also absorb at 532 nm. Simple
carbohydrates and pigments are present in many foods
of plant origin, such as juice, and these compounds are
known to interfere with the TBA assay (Baumgartner,
Baker, Hill, & Wright, 1975). To avoid the interferences
conferred by carbohydrates and pigments, improved
methods have been developed (Du & Bramlage, 1992;
Hodges, DeLong, Forney, & Prange, 1999). However,
heating (95
C) and the strong acidity used in these and
all TBA-based methods may increase oxidation and
MA formation (Yeo, Helbock, Chyu, & Ames, 1994).
Many HPLC and GC based methods have been used
for more accurate and sensitive analysis (Bird, Silas,
Hung, Hadley, & Draper, 1983; Botsoglou, Fletouris,
Papageorgiou, Vassilopoulos, Mantis, & Trakatellis,
1994; Li & Chow, 1994; Raharjo, Sofoa, & Schmidt,
1992; Spanier & Trayer, 1991). Most of these methods,
however, were still based on color reaction of MA with
TBA under elevated temperature and high acidity.
New derivatization methods have been developed
using more reactive compounds, such as penta-
fluorophenylhydrazine (PFPH) or 2,4-dinitrophenylhy-
drazine without the strong acidity and heating (Tomita,
Okuyama, Hatta, & Kawai, 1990; Wong, Yeo, & Shi-
bamoto, 1991; Yeo, Liu, Helbock, & Ames, 1999).
These derivatives could be separated by GC–MS or
HPLC. These methods have been used to assay MA in
urine, sperm and blood samples (Tomita et al., 1990;
Wong et al., 1991; Yeo et al., 1999). In the present
report, the GC–MS method (Tomita et al., 1990; Yeo et
al., 1999) was modified for analysis of MA in apple
juice, a carbohydrate-rich food and compared with the
TBA assay. The GC–MS method was also able to
simultaneously measure acetaldehyde (ACT) and
formaldehyde (FA), two compounds possibly impor-
tant in juice flavor.
0308-8146/02/$ - see front matter Published by Elsevier Science Ltd.
PII: S0308-8146(02)00110-3
Food Chemistry 77 (2002) 353–359
www.elsevier.com/locate/foodchem
* Corresponding author. Tel.: +1-215-836-3785; fax: +1-215-233-
6406.
E-mail address: xfan@arserrc.gov