This paper develops a rapid method for discriminating the geographical origins and age of roasted Torreya grandis seeds by near infrared (NIR) spectroscopic analysis and pattern recognition. 337 samples were collected from three main producing areas and produced in the last two years. The objective of geographical origins analysis is to discriminate the seeds from Fengqiao with a protected geographical indication (PGI) from those of another two provinces. Age classification is aimed to detect the old seeds produced in the last year from the freshly produced ones. Partial least squares discriminant analysis (PLSDA) was used to develop classification models, and the influence of data preprocessing methods on classification performance was also investigated. Taking second-order derivatives of the raw spectra proves to be the most proper and effective preprocessing method, which can remove baselines and backgrounds and reduce model complexity. With second derivative spectra, the sensitivity and specificity were 0.939 and 0.871 for age discrimination, respectively. Perfect classification was obtained, and both sensitivity and specificity were 1 for discrimination of geographical origins. 1. Introduction Chinese Torreya (T. grandis), a species of conifer in the Cephalotaxaceae family, is a rare cash crop tree endemic to southern and eastern China [1, 2]. The plant has been extensively used to cure cough, rheumatism, and intestine verminosis as a potent folk medicine. Various chemical components have been identified in T. grandis with an extensive spectrum of biological and medical activities, including anti-inflammatory, antihelmintic, antitussive, carminative, laxative, antifungal, antibacterial, and antitumor activities [3–7]. Its seeds are rich in proteins, fatty acids, carbohydrates, calcium, phosphorus, and iron [8]. Due to the high nutritional value, T. grandis seeds are served as a high-quality nut, and cakes, biscuits, and candies made from the seed kernels are also very popular. The seeds have an oil content of 54.62%–61.47% [8], and the oil is bright yellow with pleasant fruit flavors. The oil contains a very high level of unsaturated fatty acids, which accounts for 79.41% of the total fatty acids [8]. T. grandis seed oil is valued as a healthy and functional edible oil, and investigations have demonstrated its effects in modifying lipid metabolism, lowering triacylglycerol and cholesterol levels, and preventing atherosclerosis [9–13]. T. grandis seeds are sold in the form of a roasted nut, and the oil is often extracted by expressing the roasted
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