Dietary intake assessment of caramel colours and their processing by-products 4-methylimidazole and 2-acetyl-4-tetrahydroxy-butylimidazole for the Chinese population

ABSTRACT

The aim of the study was to assess the dietary intake of caramel colours and their by-products 4-methylimidazole (4-MEI) and 2-acetyl-4-tetrahydroxybutylimidazole (THI) for the Chinese population. Based on the typical and maximum reported use levels of caramel colours in 15 food categories, the dietary intakes of combined and single-class caramel colours of Classes I, III and IV were estimated with the food consumption data from the China National Nutrient and Health Survey. Using the mean values of 4-MEI and THI contents in Class III and Class IV Caramel colour samples, the exposures to 4-MEI and THI from dietary caramel colours were derived. The results showed that the combined and individual average dietary caramel colour intakes for the Chinese population of different age groups were estimated to be 232–60.3 mg kg⁻¹ bw day⁻¹ for combined caramels, 5.9–29.2 mg kg⁻¹ bw day⁻¹ for Class I, 7.7–29.6 mg kg⁻¹ bw day⁻¹ for Class III, 21.2–54.3 mg kg⁻¹ bw day⁻¹ for Class IV, which were far below the group acceptable daily intake (ADI) and respective ADIs. The combined intake of 4-MEI from Class III and IV caramel colours was estimated to be 3.8–5.2 μg kg⁻¹ bw day⁻¹ on average, and 12.9–27.1 μg kg⁻¹ bw day⁻¹ at 95th-97.5th percentile for the general population. The anticipated exposure to THI from Class III caramel colours was estimated to be 0.1–0.3 μg kg⁻¹ bw day⁻¹ on average and 0.5–1.7 μg kg⁻¹ bw day⁻¹ at 95th–97.5th percentile for the general population. The dietary caramel colours intakes and the exposures to 4-MEI and THI from dietary caramel colour for the Chinese population were considered to be of low health concern based on the present toxicological data. Soy sauce, vinegar and compound seasonings were found to be the main contributors to the dietary intake of caramel colours.

KEYWORDS:

• Caramel colours
• 4
• Methylimidazole
• 2
• Acetyl
• 4
• tetrahydroxy
• butylimidazole
• intake assessment

Acknowledgments

The authors gratefully acknowledge the supports of the provincial disease control and prevention centres of Jiangsu, Hebei, Zhejiang and Tianjin, China National Research Institute of Food and Fermentation Industries, China Food Additives and Ingredients Association, China National Food Industry Association, China Beverage Industry Association, China Condiment Industrial Association and the National Institute for Nutrition and Health of Chinese Center for Disease Control and Prevention.

Disclosure statement

The authors declared that they have no conflicts of interests to the work.

Additional information

Funding

This work was supported by the China Postdoctoral Science Foundation Funded Project [grant number 2016M601517].