%0 Journal Article %J J Agric Food Chem %D 2006 %T Seasonal and Variety Effects on Stable Isotope Profiling to Determine Geographic Growing Origin of Pistachios %A Kim A Anderson %A Brian W Smith %K Carbon Isotopes %K Iran %K Isotopes %K Nitrogen Isotopes %K Pistacia %K Seasons %K Species Specificity %K Turkey %K United States %X

The objectives of this study were to demonstrate if seasonal or variety differences affected the feasibility of stable isotope profiling methods to differentiate the geographical growing regions of pistachios (Pistachia vera). Bulk carbon and nitrogen isotope analyses of approximately 150 pistachios samples were performed. Isotope ratios were determined using a stable isotope mass spectrometer. The pistachio samples analyzed were from the three major pistachio-growing regions: Turkey, Iran, and the United States (California). Geographic regions were well separated on the basis of isotope ratios. Seasonal effects were found to affect some isotopes for some regions. Pistachio varieties within specified geographic regions were not found to affect the discriminating power of stable isotopes, for the varieties tested. This paper reports the development of a simple chemical profiling method using bulk stable isotope ratios that may be widely applied to the determination of the geographic origin of foods.

%B J Agric Food Chem %V 54 %P 1747-52 %8 03/2006 %G eng %N 5 %1 http://www.ncbi.nlm.nih.gov/pubmed/16506828?dopt=Abstract %R 10.1021/jf052928m %0 Journal Article %J J Agric Food Chem %D 2006 %T Stable isotope and trace element profiling combined with classification models to differentiate geographic growing origin for three fruits: effects of subregion and variety. %A Perez, Angela L %A Brian W Smith %A Kim A Anderson %K Argentina %K Blueberry Plant %K Chile %K Environment %K Fragaria %K Fruit %K Isotopes %K Mexico %K Oregon %K Pyrus %K Trace Elements %X

Classifications of geographic growing origin of three fresh fruits combining elemental profiles with various modeling approaches were determined. Elemental analysis (Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, V, and Zn) of strawberry, blueberry, and pear samples was performed using inductively coupled plasma argon atomic emission spectrometer. Bulk stable carbon and nitrogen isotope analyses in pear were performed using mass spectrometry as an alternative fingerprinting technique. Each fruit, strawberry (Fragaria x ananassa), blueberry (Vaccinium caesariense/corymbosum), and pear (Pyrus communis), was analyzed from two growing regions: Oregon vs Mexico, Chile, and Argentina, respectively. Principal component analysis and canonical discriminant analysis were used for data visualization. The data were modeled using linear discriminant function, quadratic discriminant function, neural network, genetic neural network, and hierarchical tree models with successful classification ranging from 70 to 100% depending on commodity and model. Effects of Oregon subregional and variety classification were investigated with similar success rates.

%B J Agric Food Chem %V 54 %P 4506-16 %8 06/2006 %G eng %N 13 %1 http://www.ncbi.nlm.nih.gov/pubmed/16786991?dopt=Abstract %R 10.1021/jf0600455