the near infrared spectroscopy for a rapid ... - eiranet
TRANSCRIPT
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THE NEAR INFRARED SPECTROSCOPY FOR
A RAPID ASSESSMENT OF NUTRITIONAL
QUALITY AND SAFETY
OF CEREAL GRAIN
21th FOSS Grain Network Meeting-March 18th -20th 2015, Milan
CRA-QCE
Council for Agricultural Research
and Economics
Research Unit for Cereal Quality
Rome
Department of Chemistry
University «La Sapienza»
Rome
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Quantitative analysis of cereal bioactive compounds and
mycotoxins (Deoxynivalenol, DON) by NIRS reflectance
FOSS NIR-system model 6500
400-2500 nm-2 nm
Chemical measurements
Statistically predictive equation(s)
Spectra collection
Reference data
Chemometric
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Quantitative analysis of cereal bioactive compounds
by NIRS reflectance
ARABINOXYLANS (AX)
ALKYLRESORCINOLS (AR)
Durum wheat
β-GLUCANS
Oat
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CHEMICAL MEASUREMENTS: β-glucans were measured by using the
enzymatic β-glucan assay kit (Megazyme) McCleary and Codd (1991); Åman and Graham (1987); Lee et al. (1997)
SOLUBLE β-GLUCANS TOTAL β-GLUCANS
Oat products are important sources of dietary fibre, β-glucans, proteins,
vitamins and other components, which are demonstrated to be
beneficial for human health
β-glucans improve growth, viability and colonization of probiotic
microorganisms
In general, as components of soluble fibres reduce the risk of coronary
heart disease and type 2 diabetes
Quantitative analysis of oat β-glucans by NIRS reflectance
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Quantitative analysis of oat β-glucans by NIRS reflectance
Husked and naked oat genotypes (from different European countries-
AVEQ Project):
300 genotypes (TRAINING SET) for calibration development
50 genotypes (TEST SET) for validation
NIR calibration models developed with PLS regression methods
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The VIP values, computed for each wavelength, evidence
the regions contributing the most to the regression model
for β-glucan are those between 400 and 700 nm, around
1150 nm and between 1900 and 2300 nm
Variables Importance on PLS projections (VIP)
Quantitative analysis of oat β-glucans by NIRS reflectance
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Quantitative analysis of durum wheat arabinoxylans (AX) by
NIRS reflectance
AX are one of the most important dietary fiber components in the
cereal kernels. An interesting property of AX is their ability to
form highly viscous water solutions and this peculiarity affects
the technological characteristics of flours and determines a
positive physiological influence on human health
WATER EXTRACTABLE AX (WEAX)
TOTAL AX (TOAX)
CHEMICAL MEASUREMENTS: TOAX and WEAX were determined by
GC-FID (Ciccoritti et al., 2011)
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Quantitative analysis of durum wheat arabinoxylans by
NIRS reflectance
The dataset comprised durum wheat samples (n=100/200 spectra)
grown in different Italian regions during three crop years (2012-2014)
Spectra pretreatment+PLS
AX
fractions on milled grain
Mean value
(% as is)
RMSEC RMSECV RMSEP R2
TOAX 4.11±0.27 0.159 0.205 0.266 0.659
WEAX 0.54±0.23 0.176 0.192 0.192 0.309
TOAX
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Quantitative analysis of durum wheat 5-n-alkylresorcinols
(AR) by NIRS reflectance
AR have been reported to have antioxidant, antimutagenic, anticancer (in
colon), antimicrobial, antiparasitic and antifungal activities
In plant they are thought to serve important roles as "PHYTOANTICIPINS"
CHEMICAL MEASUREMENTS: AR were measured by using the colorimetric
method FAST BLUE RR
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Quantitative analysis of 5-n-alkylresorcinols on durum wheat
milled grain by NIRS reflectance
To have a broad variability, the dataset comprised a durum wheat F6 progeny
(n=135/270 spectra) from the cross Ardente X Mohawk, showing contrasting AR
content (Mean 130 µg/g as is; range of variability 19-268 µg/g as is)
90 samples (TRAINING SET) for calibration development
45 samples (TEST SET) for validation
Spectra pretreatment + PLS regression
LV RMSE R2 Bias
Calibration
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31 0.86 0
Cross-validation 41 0.74 -1
Prediction 42 0.72 3
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NIR-based approach for quantification and/or assessment of the
contamination status. Deoxynivalenol (DON) in durum wheat
DON is one of the several mycotoxins produced by some Fusarium species
DON affects human and animal health causing acute temporary nausea,
vomiting, diarrhea, abdominal pain, headache, dizziness and fever
EU limit of 1750 ppb for wheat grain to be considered contaminated
CHEMICAL MEASUREMENTS: DON was determined by using using test
ELISA -RIDASCREEN® DON (R-BIOPHARM). [DON]=ppb
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Quantitative analysis of DON on durum wheat milled
grain by NIRS reflectance
The dataset comprised more than 200 durum wheat samples (range 750-
12350 ppb)
170 durum wheat samples (TRAINING SET)
45 samples left aside as independent test set (TEST SET)
Pre-treatment LV RMSEC RMSECV RMSEP
MSC 9 15.99 18.25 21.30
MSC+ II der. 4 14.79 19.45 20.76
oTraining set x Test set
NIR calibration model developed with PLS regression methods
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The VIP values, computed for each wavelength, evidence
the regions contributing the most to the regression
model for DON are those between 400 and 700 nm,
around 1350-1460 nm and between 2000 and 2150 nm
Quantitative analysis of DON in durum wheat by NIRS reflectance
Variables Importance on PLS projections (VIP)
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Classification analysis of durum wheat grain (sound and unsound)
by NIRS reflectance
Chemometric method of classification (SIMCA-Soft Independent
Modeling of Class Analogy) to discriminate samples on the basis
of their DON content just above (UNSOUND) and below
(SOUND) the limit set by UE regulation for durum wheat flour
(1750 ppb).
Pretreat. Class Sensitivity Specificity
Cal CV Pred Cal CV Pred
MSC SOUND 100 84.62 55.56 81.73 82.21 91.43
UNSOUND 97.11 90.38 71.43 76.93 49.22 66.67
MSC+d2 SOUND 96.15 88.46 66.67 76.81 79.90 85.71
UNSOUND 97.11 92.31 51.43 76.92 50 66.67
CONCLUSIONS
NIRS allows the rapid and accurate quantification of
different health-relevant compounds of cereals. This
results in the possibility of speeding up the overall
quality control of the samples and make breeding
programmes easier
NIR spectroscopy could be used to monitor DON
contamination in wheat, however an increase of the
dataset and robust multivariate calibrations are needed
to improve our predictive model
21th FOSS Grain Network Meeting-March 18th-20th 2015, Milan
D. Sgrulletta
R. Ciccoritti
V. Del Frate
F. Nocente