Discrimination of Inner Injury of Korla Fragrant Pear Based on Multi-Electrical Parameters

Abstract

Inner-injury fragrant pears are easily prone to rot during storage. Discriminating inner injury in the Korla fragrant pear from the normal pear is difficult as the flesh may be injured while the peel of the fruit remains intact. This study demonstrated the recognition of inner-injury pears based on their electric characteristics to pick out the inner-injury pears before storage. The electrical parameters parallel equivalent capacitance, quality factor, parallel equivalent inductance, parallel equivalent resistance, complex impedance, and phase angle were measured using the fruit electrical characteristic detection instrument. Principal component analysis and correlation analysis were used to determine the characteristic parameters, connected with the qualitative value of the fragrant pear to establish three discrimination models. When the measurement frequency was 100 kHz, compared with the Naïve Bayes and K-nearest neighbor models, the Support Vector Machine model with the characteristic parameters of quality factor, parallel equivalent resistance, and phase angle performed best. The recognition accuracy of the test set was 92.00%, the precision was 92.41%, the recall was 97.33%, and the F1 score was 0.95. Therefore, the electrical characteristic technique effectively detected the inner injury of fragrant pears and provided a new way to distinguish the inner injury of fruits.

Construction of Color Prediction Model for Damaged Korla Pears during Storage Period

“…The Korla fragrant pear belongs to the white pear system, which is a characteristic fruit and main cultivar in Xinjiang, China, and has a planting history of over 1400 years. The fruit has promising markets in China and overseas due to its dark green color, crisp and sweet taste, rich juice, thick fragrance, and high nutrient values [1,2]. However, Korla fragrant pears can be easily affected by mechanical damages at harvest, transport, classification, and packaging due to the thin pericarp and crisp pulp.…”