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Effect of the Chlorinated Washing of Minimally Processed Vegetables on the Generation of Haloacetic Acids Maria Jose Cardador and Mercedes Gallego* Department of Analytical Chemistry, Campus of Rabanales, University of Córdoba, E-14071, Córdoba, Spain ABSTRACT: Chlorine solutions are usually used to sanitize fruit and vegetables in the fresh-cut industry due to their efficacy, low cost, and simple use. However, disinfection byproducts such as haloacetic acids (HAAs) can be formed during this process, which can remain on minimally processed vegetables (MPVs). These compounds are toxic and/or carcinogenic and have been associated with human health risks; therefore, the U.S. Environmental Protection Agency has set a maximum contaminant level for five HAAs at 60 μg/L in drinking water. This paper describes the first method to determine the nine HAAs that can be present in MPV samples, with static headspace coupled with gas chromatography−mass spectrometry where the leaching and derivatization of the HAAs are carried out in a single step. The proposed method is sensitive, with limits of detection between 0.1 and 2.4 μg/kg and an average relative standard deviation of ∼8%. From the samples analyzed, we can conclude that about 23% of them contain at least two HAAs (0.995. Worth

Table 2. Percent Recovery (±SD, n = 5) of the HAAs Spiked to Vegetables at Lowa and Mediumb Levels carrot

a

compd

low level

MCAA MBAA DCAA TCAA BCAA DBAA BDCAA CDBAA TBAA average

95 94 95 96 95 92 91 90 89 93

± ± ± ± ± ± ± ± ± ±

10 10 7 7 8 8 7 9 10 8

green pepper

medium level 97 96 97 97 95 93 93 92 92 94

± ± ± ± ± ± ± ± ± ±

8 9 6 6 7 8 7 7 9 7

low level 96 94 93 95 94 90 93 92 90 93

± ± ± ± ± ± ± ± ± ±

10 10 7 7 7 8 9 9 10 8

iceberg lettuce

medium level 99 96 97 97 96 94 95 92 93 95

± ± ± ± ± ± ± ± ± ±

9 10 7 6 6 7 8 8 10 7

low level 94 92 92 91 92 91 90 89 88 91

± ± ± ± ± ± ± ± ± ±

11 11 8 7 7 8 8 9 11 9

onion

medium level 95 93 94 95 93 92 92 91 90 93

± ± ± ± ± ± ± ± ± ±

10 10 7 7 6 8 7 8 9 8

low level 95 93 94 93 93 91 92 90 91 92

± ± ± ± ± ± ± ± ± ±

10 11 7 7 7 8 7 9 10 8

spinach

medium level 99 96 96 95 95 93 93 91 91 94

± ± ± ± ± ± ± ± ± ±

10 10 6 7 6 7 7 8 9 8

low level 92 91 89 88 89 90 90 88 87 89

± ± ± ± ± ± ± ± ± ±

12 12 8 8 9 9 9 10 12 10

tomato

medium level 94 92 92 91 90 92 92 90 89 91

± ± ± ± ± ± ± ± ± ±

10 11 8 7 9 8 9 9 10 9

low level 94 92 93 92 94 94 95 93 94 93

± ± ± ± ± ± ± ± ± ±

10 10 7 6 7 7 8 8 10 8

medium level 95 93 95 96 97 96 98 96 96 96

± ± ± ± ± ± ± ± ± ±

8 9 5 5 6 6 7 7 8 7

5 μg/kg for each HAA (15 μg/kg for TBAA). b20 μg/kg for each HAA (30 μg/kg for TBAA). 7330

dx.doi.org/10.1021/jf302591u | J. Agric. Food Chem. 2012, 60, 7326−7332

Journal of Agricultural and Food Chemistry

Article

Table 3. HAA Concentrationsa (μg/kg) Found in the MPV Samples Analyzed DCAA carrot green pepper iceberg lettuce 1 iceberg lettuce 2 iceberg lettuce 3 romaine lettuce 1 romaine lettuce 2 chicory spinach 1 spinach 2 spinach 3 spinach 4 spinach 5 mixed salad 1 mixed salad 2 mixed salad 3 mixed salad 4 mixed salad 5 mixed salad 6 mixed salad 7 mixed salad 8 mixed salad 9 mixed salad 10 a

6.3 ± 0.5 NDb 15 ± 1 3.1 ± 0.2 1.4 ± 0.1 2.2 ± 0.2 3.5 ± 0.3