Determination of Chlorate in Agar Samples using Ion Chromatography
The European Food Safety Authority (EFSA) reported chlorate as a risk to human health, with possible adverse effects on iodine metabolism in the case of chronic exposure. The source of the chlorate contamination can be water used for cleaning purposes (food and work surfaces) during the food processing and production process and water used for irrigation of plants during the growing season. Chlorate, a byproduct, is formed during water treatment with chlorine, chlorine dioxide, or hypochlorite.
In June 2020, the European Commission set chlorate limits for various foods, including algae. This limit is 0.05 mg/kg for algae and other foods. Food manufacturers must ensure that their products comply with EU food regulations and, therefore, must collect data and find and evaluate chlorate sources in their production processes.
Agar is produced from red algae, e.g., Gracilaria and Gelidium, which are types of seaweed rich in agarose. Industry applies agar as a laxative, as an appetite suppressant, a vegan substitute for gelatin, a thickener for soups, ice cream, and other desserts, in fruit preserves, as a clarifying agent in brewing, for sizing paper and fabrics, and in microbiological work as a solid substrate to contain culture media.The extraction process is laborious due to the complex composition of the natural product and the presence of impurities. The seaweed extract is washed and bleached with chlorine-containing additives. Consequently, the final product needs to be controlled for the presence and concentration of chlorate.
This presentation describes a straightforward method to determine chlorate in seaweed-derived agar products. A sample preparation adapted to the matrix circumvents unwanted gelation, thus avoiding clogging capillaries and columns. Our approach is suitable for analyzing chlorate in process water or raw materials for products where the final agar content does not exceed 0.5 - 1.0 %. We simplified and automated the computation and reporting of the analytical figures of merit with the "International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use" (ICH) templates of the Thermo Scientific Dionex™ Chromeleon Chromatography Data System (CDS). Calculation and report generation within the CDS eliminates data transfer to external spreadsheet programs and transfer errors.
Presenter: Dr. Flavio Zanetti (Scientific Consultant, Biopplife Srl, Italy)
Flavio Zanetti graduated in Chemistry in 1985 with a thesis on the rheological characterization of polysaccharides. Macromolecules of natural origin have been the focus of studies undertaken in the following years, with a preference for analytical techniques used for their characterization. In particular, High Performance Size Exclusion Chromatography coupled with Low Angle Light Scattering (HPSEC-LALS) and Wide Angle Light Scattering (HPSEC-MALS) has been the focus of many years of research conducted for some pharmaceutical companies. He then gained experience in the field of safety in chemical laboratories and worked as a trainer in the field of environmental safety.
As a scientific consultant he has followed some projects on the development of advanced analytical techniques such as Ion Chromatography for the determination of contaminants in extracts of algal origin.
During recent years he has been responsible for scientific projects regarding the use of polysaccharides as support materials for microencapsulation of active ingredients. The technique is applied for the controlled release of drugs and probiotics, the masking of taste and for the manipulation and protection of cells.
