Spectral Library Searching: Mid-Infrared Versus Near-Infrared Spectra for Classification of Powdered Food Ingredient
Abstract:The objective of this study was to determine the potential of using mid- or near-infrared diffuse reflectance spectra to construct food ingredient spectral libraries for product identification and checking. Samples (106) consisting of buttermilk, dehydrated onion, cheese and milk-egg powders, wheat flours, and two powdered seasonings were scanned "as is" (not diluted with KBr using diffuse reflectance) at 4 and 16 cm-1 resolution in the mid-infrared on a Digilab FTS-60 and a Perkin-Elmer Model 2000 and in the near-infrared on an FTS-60 (4 and 16 cm-1 resolution) and NIRSystems Model 6500 scanning monochromator (10 nm bandwidth). A custom-made sample transport device was used on the FTS-60, a rotating sample cup on the NIRSystems 6500, and a stationary cell for the Perkin-Elmer 2000. Every third sample of each group was used as a test sample and searched against a library containing the remaining samples. Results showed that only full spectrum based searches with the use of Euclidian distance or correlation (with or without a first derivative) were useful. All unknowns were correctly classified by using near-infrared spectra generated on either the scanning monochromator or the FTS-60 (4 cm-1 resolution) or by using any of the mid-infrared spectra. Results demonstrated that near- or mid-infrared spectral libraries of powdered food ingredients can be used for product identification and checking.
Document Type: Research Article
Publication date: July 1, 1999
More about this publication?
- The Society publishes the internationally recognized, peer reviewed journal, Applied Spectroscopy, which is available both in print and online. Subscriptions are included with membership or can be purchased by institutional or corporate organizations. Abstracts may be viewed free of charge. Previously published as Bulletin (Society for Applied Spectroscopy)
- Editorial Board
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Request copyrighted SAS materials
- Spectroscopic Nomenclature
- Focal Point (Open Access)
- ingentaconnect is not responsible for the content or availability of external websites