portable nir (2)

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 This paper reports the results of an international cooperative research project to address potential food fraud issues related to rice supplies in China, India, Vietnam and Ghana, and as rice fraud manifests differently in each country, tailored solutions were required. A portable NIR (Near Infra-Red) instrument with chemometrics calibrated to the authentic rice, was used as a fingerprint screening method. Non-conforming or suspicious samples were analysed in a second stage (confirmatory test) using laboratory-based gas chromatograph-mass spectrometry (GC-MS) fingerprinting methods, which were developed to differentiate between: high value Basmati rice varieties and their potential adulterants; six Geographic Indicated protected rice varieties from specific regions of China; various qualities of rice in Ghana and Vietnam; as well locally produced and imported rice in Ghana. In addition, an inductively coupled plasma-mass spectrometry (ICPMS) method was developed to support the Chinese rice varieties methods, as well as a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOFMS) method for quality differentiation in Vietnam. This two stage approach permits a much higher level of on-site screening of rice samples followed by the laboratory corroborating mass spectrometry analysis to assist decision making in accepting rice supplies. 

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New NIR Method for Organic Milk

This study aimed to evaluate portable near infrared spectroscopy (NIRS) in combination with chemometrics to distinguish organic milk from other types of milk, and compare its performance with benchtop NIRS and fatty acid profiling by gas chromatography. The sample set included 37 organic retail milks and 50 non-organic retail milks (of which 36 conventional and 14 green ‘pasture’ milks). Partial least squares discriminant analysis was performed to build classification models and kernel density estimation (KDE) functions were calculated to generate non-parametric distributions for samples’ class probabilities. These distributions showed that portable NIRS was successful to distinguish organic milks from conventional milks, and so were benchtop NIRS and fatty acid profiling procedures. 

However, it was less successful when ‘pasture’ milks were considered too, since their patterns occasionally resembled those of the organic milk group. Fatty acid profiling was capable of distinguishing organic milks from both non-organic milks, even including the ‘pasture’ milks. This comparative study revealed that the classification performance of the portable NIRS for this application was similar to that of the benchtop NIRS.

                                                                                                        

                 Read the abstract at: NIR Method for Organic Milk

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