Abstract:

【Objective】The objective of this study is to enrich the evaluation index of the fruit quality of Chinese jujube, establish an identically standardized evaluating method for the fresh eating jujube and other fruits, and serve the production and research.【Method】In this paper, TA.XT plus texture analyser was used to perform the puncture test with the whole fruit of Dongzao. Through the texture detecting of Dongzao from different sources, the editing of the Macro program in the Texture Exponent 32 and the factor variance analysis of the outputing data, a suitable detecting method system of puncture test for Dongzao was established.【Result】The main method was: two points at the equatorial face of the fruit wall of a whole Dongzao fruit were selected to perform the experiment and more than 20 fruits were required to fulfill a sample test. The test conditions were listed as follows: a needle like probe (P/2n, diameter: 2 mm) was used to perform the puncture test, the speed before the test was 5 mm•s-1, the speed in the test was 1 mm•s-1, the speed after the test was 5 mm•s-1, the trigger force was 5 g, the threshold force was 2 g and the puncture distance should be less than the thickness of the flesh; After the enactment of the Macro program, the parameters could be received in the illustration curve as follows: pericarp break force (g), pericarp break distance (mm), pericarp brittleness (g•s-1), pericarp toughness (g×s), maximal flesh firmness (g), mean flesh firmness (g) and the number of peaks.【Conclusion】The detecting method could detect distinct texture of Dongzao with different water contents, storage periods or growing orchards accurately and expediently. In the same time, this method could also be applied in the texture detecting of other fresh eating jujube and other small fruits.

Key words: Zizyphus jujuba Mill. ‘Dongzao’, fruit texture, puncture test, texture analyser, detecting method