|Barton Ii, Franklin|
Submitted to: Near Infrared Spectroscopy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 27, 1998
Publication Date: N/A
Interpretive Summary: The soluble and insoluble fractions of dietary fiber have different human physiological effects and their presence in foods is of interest to consumers, the medical community, and the cereal product industry. As with total dietary fiber, the methods available for measurement of soluble and insoluble fiber are laborious and time consuming. 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 waste. Previous studies demonstrated that NIRS can be used to build a mathematical model to predict total dietary fiber content in a wide variety of cereal and grain products. The present study demonstrates that NIRS can be used to predict the insoluble fraction of dietary fiber, in a wide range of ground cereal and grain products rapidly and accurately. Use of the insoluble dietary fiber model has the potential to reduce the time required for insoluble dietary fiber analysis from 2 days to several minute and has utility for the cereal product industry.
Technical Abstract: The insoluble and soluble fractions of dietary fiber have different human physiological effects and their presence in foods is of interest to consumers, the medical community, and the cereal product industry. The development of a model, using near-infrared (NIR) reflectance spectroscopy to predict insoluble dietary fiber in a wide range of dry-milled cereal products and grains is described. The products included breakfast cereals crackers, brans, pastas, and flours. Insoluble dietary fiber was measured by the AOAC enzymatic-gravimetric procedure (AOAC 991.43). The range in insoluble dietary fiber was 0-48%. Near-infrared reflectance spectra were obtained with a scanning monochromator and data analyzed with a commercial analysis program. A calibration (n=90) was developed for prediction of insoluble dietary fiber using preprocessed spectra and modified partial least squares regression. The standard error of performance and coefficient of determination were 1.13% insoluble dietary fiber and 0.99, respectively. The results show that NIT spectroscopy can be used to predict the insoluble dietary fiber content in a wide variety of processed and unprocessed cereal products.