ARS | Publication request: THE USE OF RAMAN SPECTROSCOPY TO MEASURE PROTEIN AND AMYLOSE IN RICE

Submitted to: International Conference on Fourier Transform Spectroscopy Proceedings
Publication Type: Proceedings
Publication Acceptance Date: August 23, 1999
Publication Date: N/A

Technical Abstract: Near-infrared Fourier transform Raman (NIR-FT/Raman) spectroscopy was investigated as a method to provide a rigorous spectroscopic method by which to analyze rice flour for protein and apparent amylose content. Ninety rice samples from a 1996 collection of short, medium and long grain rices grown in 4 states of the United States, Taiwan, Korea and Australia were investigated. Milled rice flour samples were scanned in rotating cup with a 1064 nm NIR laser at 500mW of power. Raman scatter was collected and focused on a Ge (LN2) detector. Data over the shift range of 200-3600 cm**-1 was utilized in the study. The spectral data was preprocessed by two methods: [1] 1st derivative or [2] baseling correction with normalization. Nearly equivalent result were obtained using either preprocessing method with PLS1 models. Models using baseline correction were slightly better and thus were selected for use. The model for protein n(n=86) with 7 factors gave r**2=-0.998 with SECV=0.157% and bias=-0.0003%. The model for apparent amylose (n=86) with 12 factors gave r**2=0.982 with SECV=1.09% and bias=0.026%.