Analysis of ethylene oxide in ice creams manufactured with contaminated carob bean gum (E410)

Figures & data

Table 1. Selected analytical approaches for the analysis of EO and/or 2-CE in foodstuffs

Technique	Sample preparation	Target analyte(s)	Quantification	Foodstuffs	LoD or LoQ (mg/kg)	Reference
GC-FID	Acetonitrile/methanol extraction	2-CE	Standard addition	Dried spices & condiments	1 (LoD)	Aitkenhead and Vidnes 1988
GC-ECD	Conversion of 2-CE to EO, distillation, treatment with NaI/H2SO4, ethyl acetate extraction	EO + 2-CE	External calibration	Herbs, spices, cocoa products, tea, honey	0.050 (LoD)	Jensen 1988
GC-FID	Head Space (HS)	EO	Matrix-matched calibration	Spices	1 (LoQ)	Woodrow et al. 1995
GC-ECD	Conversion of 2-CE to EO, distillation, treatment with NaI/H2SO4, ethyl acetate extraction	EO + 2-CE	External calibration	Spices	0.010–0.030 (LoQ)	ASU 1999; Gilsbach and Weeren 1999; Anastassiades, 2021
GC-MS	Treatment with NaCl/H2SO4, ethyl acetate extraction	EO + 2-CE	External calibration	Pepper (black, white, green), peppercorn	0.020 (LoD) 0.100 (LoQ)	Tateo and Bononi 2006
GC-MS	Treatment with NaCl/H2SO4, ethyl acetate extraction	EO + 2-CE	External calibration	Herbs, spices & dried vegetables	0.010 (LoD) 0.050 (LoQ)	Bononi et al. 2014
GC-MS	Solid-phase microextraction (SPME)	EO	External calibration	Grain, oilseeds, nuts, dried fruits	0.001 (LoQ)	Du et al. 2019
GC-MS/MS	QuEChERS and/or QuOil extractions	EO + 2-CE	Matrix-matched or external calibrations (isotope dilution)	Dried foods	0.050 (LoQ)	EURL SRM 2020
GC-MS/MS	Treatment with NaCl/H2SO4, QuEChERS extraction	EO + 2-CE	External calibration (isotope dilution)	Ice cream	0.010 (LoQ)	This study

Figure 1. GC-MS/MS chromatogram of 2-CE in an ice cream sample containing 0.017 mg/kg of EO (2-CE = 0.032 mg/kg) and its internal standard fortified at 0.020 mg/kg 2-CE

Table 2. Performance of the GC-MS/MS method for the quantitative determination of 2-CE in ice cream by isotope dilution

	Amount of 2-CE (mg/kg)^a
	0.02 (0.011)	0.04 (0.022)	0.10 (0.055)
Recovery (%)	95	87	104
RSDIR (%)	28.0	6.3	0.1

^aEO equivalent in parenthesis (mg/kg)

Figure 2. GC-HRMS chromatograms of a chemical standard of 2-CE (top) and an ice cream extract contaminated with 2-CE (bottom). Two chlorine atom-derived fragment ions at m/z 78.9945 (from ³⁵Cl) and m/z 80.9916 (from ³⁷Cl) are shown as well as the ion at m/z 31.0178

Figure 3. Correlation of EO levels measured by two independent laboratories (n = 23). Note, some data points (n = 7) are superimposed at the origin (below LoQ)

Figure 4. Fate of EO and 2-CE under different thermal conditions. Ice cream was fortified at 0.5 mg/kg EO or 1 mg/kg 2-CE before heat treatment and analysis. Results are expressed in EO equivalent (n = 3 independent determinations)

Figure 5. EO levels determined with or without conversion of EO to 2-CE during extraction in n = 32 ice cream samples. Levels are expressed in EO equivalent

Figure 6. Possible chemical and biological pathways to EO and 2-CE from ethylene

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