Overcoming Sample Preparation Challenges

Jeffrey Abels has more than 40 years of experience in lot sampling, inspection, grading and testing of dried fruits, tree nuts, peanuts, spices, edible seed, pulses, fruit concentrates, green coffee, and cocoa. He attended Rutgers University for undergraduate and graduate studies in food science and entomology. Abels has conducted inspections of processing facilities throughout the Middle East and Asia, and has expertise in the investigation of stored product insect infestations, insect identification, and microanalytical entomology. He is the owner of the Foreign Trade Service Corporation, with offices in Houston, TX, and ISO 17025 accredited laboratories in Newark, NJ and Chesapeake, VA. Abels is the Chairman of the Food Science Section of the American Council of Independent Laboratories.

Q: There seems to be an increasing awareness on food safety and consumers wanting to know what exactly is in their food products. Can you comment on the overall importance of proper sample preparation within food testing specifically?

A: You cannot separate the importance of unbiased sampling and proper sample preparation from the analysis. A laboratory might have the finest scientists, state-of-the-art scientific instruments, and validated methods with very low detection limits. However, if the sample is not representative of the lot or if it has not been properly prepared, the test data is irrelative.

Q: What are some of the common challenges encountered with sample preparation methods? Do you face any unique obstacles specific to your work?

A: At FTS Laboratories our goal is to become a much “greener” laboratory— one that uses fewer hazardous reagents and smaller volumes. As a laboratory that primarily serves importers and processors of tree nuts, peanuts, and edible seed, we run a high volume of indicator tests for rancidity. Standard methods for sample preparation involve isolation of the lipids by Soxhlet extraction. This takes considerable time and uses more solvent than we would like.

Q: How do you overcome these challenges? What type of instrumentation are you using to ensure proper sample prep practices?

A: We were introduced to the CEM Edge at a trade show, and requested a demonstration at our laboratory. The Edge extracts the oil from the sample in a very short amount of time using a very small volume of solvent. The Edge system then goes through a programmed clean-up procedure. The total process usually takes about 12-15 minutes. We then use a nitrogen evaporator to remove the residual solvent, and that takes about 40 minutes. In contrast, the Soxhlet method takes many hours. We have also found in our laboratory that the extracted portion is much cleaner.

Q: How has the introduction of automated sample prep affected prep practices?

A: In an age when your thumbs can instantly connect you to the world via your smart phone, clients expect test results yesterday. Any technology that can prepare samples and test samples faster is indispensable in the modern laboratory. The CEM Edge is now an integral part of our sample preparation procedures. We can also use the Edge to prepare samples for pesticide residue testing and other analyses.

Q: Any advice for those who find sample prep complicated or overwhelming?

A: Consider implementing innovative instruments into your lab. FTS Laboratories is in the business of testing food, but the Edge is used in environmental, pharmaceutical, and other types of laboratories.