Page Banner

United States Department of Agriculture

Agricultural Research Service


Location: Quality and Safety Assessment Research Unit

2007 Annual Report

1a.Objectives (from AD-416)
The goal of this project is to develop and compare rapid, accurate, improved (non-destructive) and environmentally benign spectral methods to replace invasive, less accurate and less rapid current methods of analysis to determine the quality and functional end product use of agricultural commodities and food products and to assist regulatory agencies in objectively measuring and predicting quality and functionality. Specifically this involves sub-objectives to:.
1)Develop an accurate method for determining starch amylose/amylopectin ratios as a measurement of grain quality to facilitate its genetic development/functionality for foods, biobased products, and biofuels..
2)Facilitate compliance with the Nutrition Labeling and Education Act (NLEA) by the development of rapid, accurate and environmentally benign spectroscopic methods for: total dietary fiber in mixed foods; for rapid analysis of fats in cereal and snack foods; and rapid analysis of trans-fatty acids in snack foods..
3)Develop methods for cotton to detect stickiness and identify trash, factors that adversely affect quality..
4)Develop methods to determine the fiber content of the standing flax plant to predict proper harvesting time and for the assessment of retted flax that provides a measurement of shive (trash) content. .
5)Determine the relationships among sensory, physical, and chemical properties of poultry meat that result from non-traditional processing, such as applications that hasten the onset of rigor or air-chilling to reduce water use..
6)Determine the relationships among sensory, physical, and chemical properties of poultry meat that result from further-processing treatments, such as marination to increase yield and improve sensory quality.

1b.Approach (from AD-416)
This project has multiple approaches for the objectives:.
1)Proton high-resolution magic-angle-spinning (HR MAS) nuclear magnetic resonance (NMR) will be employed to measure the branching in grain starch based on the ratio of the areas of the anomeric protons (1-4/1-6). The data so obtained will serve as reference data for use in chemometric calibrations for vibrational spectroscopic techniques (near-infrared [NIR], mid-infrared [MIR] and Raman) to provide more accurate rapid analysis methods..
2)Analysis of dietary fiber in mixed meals will be conducted by homogenizing the samples and analyzing sub-samples for total dietary fiber (TDF) by Association of Official Analytical Chemists (AOAC) Method 991.43 as the reference method. Off-the-shelf cereal and snack foods will be milled and analyzed for total fat using AOAC Method 996.01 as the reference method. Fatty acids will be extracted and analyzed for the proportion of trans-fatty acids by gas chromatography (GC) as the reference method. Samples will be scanned with diffuse refection NIR and/or MIR spectrometers. Chemometric models will be developed to relate spectra to reference data and used to predict: dietary fiber; total, saturated, and trans-fat in test mixed meals; cereal products; and snack food samples..
3)Obtain stickiness values on cotton fiber samples by mini-card system as reference values. Scan samples with high-resolution NIR spectrometers. Develop spectroscopically based classification models. Export model to a field analysis based system. Integrate the system with remediation technologies..
4)Collect samples of all anticipated foreign matter (trash) that could potentially be present in cotton. Scan samples using attenuated total reflectance/Fourier transform-infrared (ATR/FT-IR). Build database of spectra. Validate with known samples and test the database using unknown samples. Identify unknown foreign matter in cotton. Develop a set of samples prepared from physically separated pure fiber and shive of flax. Grind and prepare weighed mixtures of components. Scan these samples using laboratory based NIR spectrometers. Develop a chemometric calibration for fiber and shive content of the samples. Use this calibration to predict the fiber and shive content of as-is and retted flax..
5)Develop comprehensive profiles of the measurable sensory attributes of foods and food products and relate these profiles to the food's physical and chemical properties in order to enhance product development and accurately predict end-use quality. Develop indexes, methods, or strategies to predict, evaluate, modify, and control end-use quality based on data-relationships..
6)The overall framework of the research involves six steps; (a) Develop specific sensory objectives relating to the commodity problem; (b) Select the range of characteristics encompassed by the problem that will be tested; (c) Develop the appropriate databases of sensory, chemical, physical properties; (d) Pre-process the data using multivariate methods; (e) Develop and test models to explain and predict sensory quality; (f) Test selected variables in more stringent experimental designs.

3.Progress Report
The prototype field portable NIR developed in 2006 was taken to the field and used to detect sticky cotton in cotton modules at a large cotton gin operation. Corn starch was evaluated by NMR for its branching composition. A commercial hand-held NIR was calibrated and used successfully to predict the shive content of ground flax samples. Because of this a commercial producer is considering adopting the technology. An attenuated total reflection infrared technique was developed to determine trans-fatty acids without extraction of the oil from foods that reduces the analysis time for trans-fats to 60 sec. A rapid NIR analysis was developed and transferred to another laboratory for both whole kernels and ground barley for 6 chemical components. This eliminates many hours of wet chemical analysis in the analysis of grains as sources of bio-fuels. Sensory descriptive flavor and texture profile and instrumental data were collected on chicken broiler breast fillets from air chilled versus water chilled carcasses to investigate the relative attributes of each method. Sensory quantitative descriptive analysis and instrumental methods were used to validate a new cooking method (combi oven) for sensory sample preparation. Work was begun on developing an instrumental method to predict the juiciness (sensory) of chicken meat. Development of a rapid fluorescence method for the detection of pathogens in foods was continued and improved. Work was begun on infrared and Raman mapping of bran tissues in order to specifically locate phenolics for isolation as co-products from bio-fuel processes.

Subordinate Projects:

SCA #58-6612-4-0252: A new semi-portable NIR instrument was developed by adapting an existing mid-infrared instrument. This was used to scan cotton modules for sticky cotton at a large ginning operation. In addition modules were scanned with a small fluorescence device that was developed. The PI, with the assistance of a Ph.D. student, additional search algorithms were to more efficiently search our cotton trash data base. New smaller instruments are being sought for development for multiple spectral regions.

NFCA #58-6612-5-0258: A consumer panel results showed that taster status has only limited impact on consumption of the selected foods prepared with artificial sweeteners. Descriptive sensory profiles are now being developed on reformulated cupcakes and cookies prepared with artificial sweeteners.

SCA #58-6612-2-203 was closed out on 12/26/06. This work showed that: near-infrared reflectance spectroscopy provides a rapid and environmentally benign technique for prediction of total fat for the food industry and monitoring agencies. It was also shown that NIR spectroscopy can be a tool for the prediction of lipid classes in processed cereal products.

All SCAs were monitored by observing and directing students in our laboratory, bi-weekly visits by the PI, plus e-mail correspondence between SYs concerned and the PIs.

Spectroscopic determination of trans-fat in processed cereal products. Traditional methods of trans-fat analysis of foods are time consuming and solvent based. An attenuated total reflectance infrared method was developed for the rapid and environmentally benign analysis of total trans-fat in ground, processed cereal products. The method facilitates compliance with the U.S. N.L.E.A. and supports improved human health. This relates to milestones sub-objective 2.3, milestone 5 and component 1 of the National Program Action Plan: Quality, Characterization and Preservation under NP306, and specifically problem areas 1a & 1b.

5.Significant Activities that Support Special Target Populations
Significant activities that support target populations None.

6.Technology Transfer

Number of non-peer reviewed presentations and proceedings20

Review Publications
Himmelsbach, D.S., Hellgeth, J.W., Mcalister III,D.D. 2006. Development and use of an attenuated total reflectance transform infrared (ATR/FT-IR) spectral database to identify foreign matter in cotton. Journal of Agricultural and Food Chemistry. 54(20):7405-7412.

Kim, Y., Himmelsbach, D.S., Kays, S.E. 2007. ATR-fourier-transform mid-infrared spectroscopy for determination of trans fatty acids in ground cereal products without oil extraction. Journal of Agricultural and Food Chemistry. volume 55. pages 4327-6333. 2007.

Kim, Y., Singh, M., Kays, S.E. 2007. Near-infrared Spectroscopic Analysis of Macronutrients and Energy in Homogenized Meals. Food Chemistry. Volume 105: pages 1248-1255, 2007.

Last Modified: 8/19/2014
Footer Content Back to Top of Page