Iran, USA, Turkey, Syria, Italy, Tunisia, and Greece are the main pistachio producers in the world. In Iran, pistachio is the most important commercial agricultural product cultivated and the export provides the highest financial income among Iran’s non-petroleum export products, making Iran one of the world’s largest pistachio exporters. Over the past 50 years, Iranian pistachio production has grown dramatically, with currently around 380,000 hectares for an annual production of 350,000 tons. The number of pistachio trees in Iran is estimated at more than 80 million that include 17 major cultivars.
Kerman province, producing 90% of the pistachios in Iran, with 270,000 hectares, is the most important region for growing pistachio in Iran and in the world. Although Iran is one of the main centers for pistachio diversity in the world, Iran’s pistachio industry relies mainly on a limited number of cultivars, including Ohadi, Ahmad-Aghaei, Fandoghi, Akbari, and Kalle-Ghouchi, which cover more than 95% of the cultivated area.
Scientists at the University of Zanjan (Iran) have determined by gas chromatography the fatty acid profiles [palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0), oleic (C18:1), linoleic (C18:2), linolenic (C18:3), arachidic (C20:0), and gondoic (C20:1) acid] of five main commercial pistachio cultivars, including Ahmad-Aghaei, Akbari, Chrok, Kalle-Ghouchi, and Ohadi, to classify the different cultivars in Iran in terms of quality index, oxidative stability and shelf-life.
"The quality index, based on the oleic to linoleic acid (O/L) ratio, for these five cultivars resulted: Ohadi (2.40) < Ahmad-Aghaei (2.60) < Kale-Ghouchi (2.94) < Chrok (3.05) < Akbari (3.66). The study has demonstrated the potential of GC as method for the traceability and classification of Iranian pistachio nuts based on their fatty acid composition - the scientists explain - A classification model with high sensitivity was constructed to predict the cultivars of the samples, which were then evaluated by cross-validation and additionally by the external test set. The outcome for this classification approach is very satisfying: the cultivars of the validation samples were classified correctly by LDA modeling in more than 98% of cases. The models are very sensitive and highly specific for authenticating the provenance of pistachio nuts. The high predictive power for the prediction set shows the ability to indicate the cultivar of an unknown sample based on its fatty acid chromatographic fingerprint".
Source: Mahnaz Esteki, Parvin Ahmadi, Yvan Vander Heyden and Jesus Simal-Gandara, 'Fatty Acids-Based Quality Index to Differentiate Worldwide Commercial Pistachio Cultivars', 2019, Molecules, 24, 58; doi:10.3390/molecules24010058.