Fat extraction from food is a necessary procedure in the food industry in terms of product formulation. This is because all food labels are required to report both the saturated and unsaturated fat content of their products. In addition, consumers would also intend to determine the contents of their food, especially in terms of fat.
In an industry with lots of quality control and that is increasingly becoming more consumer-driven, time becomes a critical factor. Food manufacturers are concerned with additional testing prior to product release, making speed of analysis a critical factor.
In this article, presented is the capability of EDGE®, with its patent pending Q-Cup Technology™, to extract total fat from hot dogs and potted meat in less than less than five minutes.
Total fat extraction is challenging because there is a risk of fat getting trapped within the matrix. A traditional method like Soxhlet is effective, but requires lots of time and solvent, in addition to being destructive to the sample. The food industry nowadays requires a method wherein fat content could be determined quicker and safer.
Apart from food labeling needs, it is also important to analyze food contaminants. In doing so, there is a need to further process a sample after fat extraction, but as most traditional methods would just destroy the sample after the process, doing additional analyses is not possible.
With EDGE, fat extraction from hot dogs and potted meat could be completed in less than five minutes. The EDGE process is non-destructive, enabling the extracted sample to be ready for further analysis. Included in the run time are the extraction, filtration, cooling, and system washing.
The EDGE uses the Q-Cup Technology that combines pressurized fluid extraction and dispersive solid phase extraction in a single instrument that produces rapid and efficient extraction. The easy-to-assemble Q-Cup™ sample holder boasts of a unique open cell concept that creates a dispersive effect and facilitate rapid extraction and filtration. The result is fast, simple, and efficient extractions.
It is easy to setup a sample preparation using the EDGE. A Q-Disc™ must be placed in the Q-Cup base, and the two parts must be screwed together. A sorbent or drying agent may be added along with wet or dry food samples not exceeding five grams.
Figure 1. The EDGE Process
The EDGE will utilize only 40 mL of solvent per extraction, which includes solvent for diffusive extraction and sample rinse. During system cleaning, the device may use up to an additional 30 mL of solvent. The rapid heating of the extraction chamber combined with diffusive action enables a temperature of up to 180°C to be achieved in less than two minutes.
Sample is Loaded
The Q-Cup is automatically loaded into the chamber by the auto sampler. The pressure cap then creates a pressurized seal on the top of the Q-Cup.
Solvent is Extracted
Solvent is first added through the bottom to fill the gap between the chamber and Q-Cup, aiding in heat transfer. The solvent is then added through the top of the Q-Cup to wet the sample.
As the chamber walls are heated, the pressure in the gap increases. This process overcomes the pressure inside the Q-Cup, forcing the solvent to disperse into the sample.
Extract is Collected
Once the sample reaches the target temperature, the solvent is dispensed through the Q-Disc, the cooling coil, and into a collection vial.
Procedure and Method
The hot dog and potted meat samples were homogenized in a grinder and then dried in an oven at 120°C for one hour. One gram samples of hot dog or potted meat were mixed with one gram of sand. They were then added to an assembled Q-Cup containing a Q-Disc. The Q-Cups were placed in the EDGE removable rack, each with a collection vial, and the rack was slid into place on the EDGE.
The One Touch Method™ for total fat was used. The extracts were transferred to pre-weighed centrifuge tubes and then dried using a Genevac EZ-2 Plus Evaporating System. The dried samples in the centrifuge tubes were weighed to determine total fat.
Nathan’s® Famous skinless beef franks and ARMOUR® Star potted meat were purchased from a local grocery store. Samples were mixed with sand from Sigma Aldrich. Samples were extracted using both the EDGE and Soxhlet, while petroleum ether was used as the extraction solvent. The system was washed with petroleum ether and water.
Results and Discussion
The EDGE, through its Q-Cup Technology, yielded comparable results to Soxhlet for the total fat extraction of hot dogs and potted meat in less than five minutes. Table 1 presents the recovery data, in comparison to Soxhlet, for the extraction of fat from hot dogs and potted meat. With EDGE, the total fat of hot dogs and potted meat was speedily determined using minimal solvent in a one-step simple process. As expected, the samples were not destroyed and could be further processed, if necessary.
Table 1. Recovery data for the extraction of fat of hot dogs and potted meat versus Soxhlet
|Sample||% Recovery versus Soxhlet|
This information has been sourced, reviewed and adapted from materials provided by CEM Corporation – Analytical.
For more information on this source, please visit CEM Corporation – Analytical.