ARS | Publication request: Accelerated solvent extraction of alkylresorcinols in food products containing uncooked and cooked wheat

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 24, 2012
Publication Date: May 24, 2012
Citation: Holt, M.D., Moreau, R.A., Dermarderosian, A., Mckeown, N., Jacques, P.F. 2012. Accelerated solvent extraction of alkylresorcinols in food products containing uncooked and cooked wheat. Journal of Agricultural and Food Chemistry. 60:4799-4802.

Interpretive Summary: Alkylresorcinols are a group of phytonutrients that are found in wheat, rye and other gluten-containing cereals. Alkylresorcinols appear to function as antioxidants but their exact physiological function in plants and their nutritive value is not known. Alkylresorcinols have been shown to be potential markers for the consumption of whole grain foods that contain rye and wheat. The levels of alkylresorcinols measured in blood and urine samples have been shown to be proportional to the amounts of whole grains that are eaten. Because the traditional way to extract alkylresorcinols is very tedious and labor-intensive, the study described in this paper was undertaken to try to identify a more convenient automated method for the extraction of alkylresorcinols in foods. Fortunately, this new method, which employs an instrument called an Accelerated Solvent Extractor, was shown to be a more convenient way to extract alkylresorcinols. This study showed that the levels of alkylresorcinols extracted with the traditional method and the Accelerated Solvent Extractor were nearly identical, so the new method should be an attractive alternative to the traditional method.

Technical Abstract: This research focuses on the overall extraction process of alkylresorcinols (ARs) from uncooked grains and baked products that have been processed with wheat, corn, rice, and white flour. Previously established extraction methods developed by Ross and colleagues, as well as a semi-automated method involving Accelerated Solvent Extraction (ASE) were applied to extract ARs within freshly ground samples. For extraction of alkylresorcinols, non-polar solvents such as ethyl acetate have been recommended for the extraction of uncooked foods and polar solvents such as 1-propanol: water (3:1 v/v) have been recommended for the extraction of baked foods that contain rye, wheat, or other starch-rich grains. Comparison of AR extraction methods have been investigated with the application of gas chromatography and a flame ionization detector (GC: FID) to quantify AR content. The goal of this research was to compare the rapid accelerated solvent extraction of alkylresorcinols (ASE-AR) method to the previous manual AR extraction methods. Results for this study as well as the investigation of the overall efficiency of ASE-AR extraction with the use of a spiking study indicated that it can be comparable to current extraction methods but with less time required. Furthermore, the extraction time for ASE (approx. 40 minutes) is much more convenient and less tedious and time-consuming than previously established methods, which range from 5 hours for processed foods to 24 hours for raw grains.