|Barton Ii, Franklin|
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 16, 1996
Publication Date: N/A
Interpretive Summary: To aid consumers in selecting a healthy diet, the United States Nutritional Labeling and Education Act (NLEA) requires that the amount of total dietary fiber be included on food labels. The method currently used for dietary fiber analysis in the U.S.A. is time consuming and personnel intensive. Near-infrared reflectance spectroscopy (NIRS), which measures the amount of light energy reflected by a substance, represents a very rapid and accurate method of measuring constituents of materials without requiring extensive sample preparation, nor creating chemical pollutants. Very little is known about the potential of NIRS technology to determine total dietary fiber in foods. This study determined that NIRS can be used to accurately determine the total dietary fiber content of ground breakfast cereals, crackers, brans, and flours containing less than 10% fat and less than 20% sugar. Our development of NIRS technology for total dietary fiber analysis will provide cereal industries with tools to meet regulatory mandates for food composition, thus allowing compliance with the NLEA. Our results will also provide regulatory agencies with quick, simple, and efficient methods for monitoring compliance.
Technical Abstract: This study investigated the use of near-infrared reflectance spectroscopy for the prediction of total dietary fiber content of cereal products. Cereal and grain products, including breakfast cereals, flours, brans, crackers, and commercial oat fibers were selected for analysis. Products (n=91) were dry milled and total dietary fiber measured by the AOAC (991.43) enzymatic-gravimetric method. Total dietary fiber values ranged from <1 to 52% of dry weight. Milled cereal products (n=91) were scanned from 1100 to 2498 nm with a NIRSystems 6500 monochromator. Using ISI software for scanning and data analysis, a dietary fiber calibration was obtained with partial least squares as the regression method. The standard error of cross validation and multiple coefficient of determination (R**2) were 1.58% and 0.99, respectively. For equation validation an independent group of cereal products (n=31) was dry milled and total dietary fiber determined. The samples were scanned and total dietary fiber predicted by near-infrared reflectance spectroscopy. Samples were predicted with a standard error of performance of 1.51%, coefficient of determination (r**2) of 0.99, bias of -0.38, and slope of 1.06. This study shows that near-infrared reflectance spectroscopy can be used to predict, rapidly and accurately, total dietary fiber content in a wide range of cereal products.