Determine Migration in Food Packaging with Thermal Extraction

Knowledge about the interaction between food packaging and food is of great importance to the food industry. Both the possible transfer of food components to the packaging and the migration of unwanted compounds from the packaging to the food can have an effect on the taste or odor.

Analysis by Direct Thermal Extraction

A GERSTEL application note describes how this possible transfer can be determined for the packaging of cookies, crackers and sweets. For this purpose, a GERSTEL MultiPurpose Sampler (MPS) has been combined with a Thermal Desorption Unit (TDU) and a Cooled Injection System (CIS 4) PTV-type Inlet for an automated Direct Thermal Extraction (DTE) analysis. The results show that direct thermal extraction is a very good method for quantification and assessment of possible transfer of compounds between packaging and food products.

A small amount of the sample, typically 10-50 mg, is placed in an empty thermal desorption tube and then it is heated under a stream of inert gas in the thermal desorption unit to release volatile and semi-volatile compounds from the sample . The analytes are collected and then determined via a GC/MS system.

Benefits of Thermal Extraction

Direct thermal extraction requires little sample preparation and can be used for trace analysis of the packaging material. For example, this extraction revealed the compound benzaldehyde in one brand of candy packaging and found to be 79 ± 6 ng in 25 mg of the packaging.

The GERSTEL solution offers an analyst a large number of analytical options for chemical analysis. This allows the analyst to easily switch between liquid and high volume injection, solid phase microextraction (SPME) and static headspace analysis, depending on the analytical needs at the time.
The use of the TDU module enables thermal desorption, direct thermal extraction, Twister and Thin Film SPME analyses. Other options include Dynamic Headspace (DHS), another thermal extraction technique, and pyrolysis. Changing the modules is easy to adapt for a new analysis.

Would you like to know more about Thermal desorption or extraction? Then visit our stand B066 at WoTS in Hall 7 or download the application note.