February 15-18, 2009 Washington State Convention Center Seattle ...

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THE USE OF FOURIER TRANSFORM INFRARED SPECTROSCOPY TO PREDICT
OVARIAN ATRESIAAND CAVIAR QUALITY IN WHITE STURGEON (Acipenser
transmontanus)
Xiaonan Lu and Barbara Rasco
School of Food Science
Washington State University
Pullman, WA 99163 USA
xiaonan_lu@wsu.edu
Fourier Transform Infrared Spectroscopy (FT-IR, 4000-400 cm -1 ) spectral features of white sturgeon (Acipenser transmontanus)
(N=11) plasma and roe were determined over a nine month period to predict when fish entered atresia. The objective was
to determine whether changes in spectral features could be used to predict caviar quality. FT-IR spectra of plasma changed at
various maturity levels. Differences in plasma biochemical composition in the sex steroids region (around 3000 cm -1 ) were
detected along with changes in the concentration of plasma vitellogenin (around 1080 cm -1 ). By using Principal Component
Analysis (PCA), it was possible to clearly segregate fish by maturity stage due to differences in spectral features of the plasma.
The stage of maturity (late vitellogenesis vs. early atresia) could be predicted ~ 70% of the time using Soft Independent
Modeling of Class Analogy (SIMCA) models. Also, a rigorous Partial Least Squares (PLS) model was established to predict
Polarization Index (PI) values between 0.1 and 0.3 (R=0.98, SEP=1.01%) based upon differences in plasma spectral features
(Fig.1). FT-IR spectra of fish plasma may provide a useful tool for assessing sexual maturity in female sturgeon. Few changes
were observed in spectral features of the roe recovered during late vitellogenesis or early atresia. This technique may reduce
the need for traditional invasive and stressful surgical biopsy methods for PI determination currently used to predict the timing
of roe harvest.
Figure 1. Comparison between actual and predicted PI values
(range: 0.1 and 0.3) for sturgeon females