Overview
Kowaluk and colleagues tested deep eutectic solvents with ultrasound as a green alternative to acid digestion for extracting elements and antioxidants from gingerbread. They used two products, one uniced and one iced, from a Polish confectionery company. Table 2 compares solvent extracts with a microwave acid digestion, measured by ICP-MS. Cadmium was below the detection limit in every digest and extract.
Key numbers
- Cadmium: below LOD in uniced and iced gingerbread after microwave digestion and in all solvent extracts (Table 2, p. 10).
- Microwave digestion, uniced and iced: iron 12.32 ± 0.01 and 11.55 ± 0.40 mg/kg; zinc 5.63 ± 0.20 and 5.01 ± 0.10 mg/kg; copper 0.58 and 0.48 mg/kg (Table 2, p. 10).
Methods (brief)
Powdered cookies were digested by microwave-assisted acid digestion, or extracted with three acidic deep eutectic solvents in an ultrasound bath, then analyzed on an Agilent 7800 ICP-MS with helium collision gas. INCT-PVTL-6 tobacco leaves reference material was used for recovery. The cadmium detection limit is not printed. Each value is the mean of two preparations.
Evidence Fitness
A methods paper with only two products from one maker, so it gives a single cadmium non-detect rather than an occurrence estimate, and the unstated detection limit limits its use. Lead and arsenic were not measured. Only the total-digestion values are recorded, because the solvent extracts measure partial extraction. Gingerbread is a baked-sweet proxy for blueberry-muffin, doughnut and white-cake; those pages are not linked.