Submitted to: Food Chemistry
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/17/2007
Publication Date: 11/27/2007
Citation: Robinson, J.E., Singh, R., Kays, S.E. 2007. Evaluation of an automated hydrolysis and extraction method for quantification of total fat and lipid classess in cereal products.. Food Chemistry, Vol. 107, pages 1144-1150. Interpretive Summary: To obtain accurate information on the fat content of various foods accurate and repeatable methods are required for the analysis of total fat and lipid classes in foods. AOAC 996.01 is a universally accepted method for the determination of total, saturated, polyunsaturated, and monounsaturated fat in cereal-based products and has sufficient accuracy and repeatability to satisfy current nutrition labeling regulations. A modification of AOAC 996.01 can be used for measurement of trans fatty acids. Although accurate and repeatable, AOAC Method 996.01 and similar methods are laborious, time-consuming and use large volumes of organic solvents, which are hazardous, flammable and require specific disposal. An automated hydrolysis and extraction (AHE) system available commercially, offers an alternative to AOAC Method 996.01. Because the AHE system is automated and closed it is safer for the operator, takes less of the operator’s time and uses less solvent. The objective of this study was to evaluate the AHE system for the determination of total fat gravimetrically and for the extraction of fat for capillary GC determination of total fat, lipid classes and trans fat in cereal products. A diverse range of cereal products was used for the study and the results were evaluated against those using AOAC Method 996.01 as the standard. For gravimetric and gas chromatographic evaluations the AHE system results were equivalent to those using the standard AOAC method, indicating that the AHE system can be used to measure total, saturated, polyunsaturated, monounsaturated and trans fat with sufficient accuracy for nutrition labeling purposes while having the advantages of reduced use of solvent, operator exposure to solvent, operator time and operator error.
Technical Abstract: The utility of an automated acid hydrolysis-extraction (AHE) system was evaluated for extraction of fat for the quantification of total, saturated, polyunsaturated, monounsaturated, and trans fat in cereal products. Oil extracted by the AHE system was assessed for total fat gravimetrically and by capillary gas chromatography (GC) for total fat, lipid classes, and trans fat. All AHE system results were compared with parallel determinations using the standard AOAC Method 996.01. For gravimetric and gas chromatographic evaluations the AHE system results were equivalent to those using the standard AOAC method ('=0.01), indicating that the AHE system can be used to measure total, saturated, polyunsaturated, monounsaturated and trans fat with sufficient accuracy for nutrition labeling purposes, while having the advantages of reduced use of solvent, operator exposure to solvent, operator time and operator error.