# Analysis of the Aroma Chemical Composition of Commonly Planted Kiwifruit Cultivars in China
## 1 Introduction  
Kiwifruit (_Actinidia chinensis_ Planch) is one of the most commercially valuable fruit species [1]. With the development of the kiwifruit industry and the progress of breeding technology based on Hayward and Hort16A, some countries have bred a number of new kiwifruit cultivars and promoted their cultivation. A large number of new cultivars of kiwifruit have been bred and widely cultivated also in China, the country of origin of kiwifruit, as a consequence of the rise in kiwifruit industry. Since 2000, the area and output of kiwifruit have been the largest in the world (Date from FAO: 1961-2018). The genus _Actinidia_ consists of more than 50 species. At present, _A. chinensis_ Planck, var. _chinensis_ (_A. chinensis_) and _A. chinensis_ var. _deliciosa_ A. Chevalier (_A. deliciosa_) are the most commercially valuable species [2, 3]. Currently, Chinese kiwifruit are mainly sold in the domestic market, and the prices are generally low. The price is usually one-fifth to one-third of imported kiwifruit. Additionally, there is still a large demand for kiwifruit imports in the domestic fresh fruit market, and the price is much higher than that of domestic kiwifruit. In addition, Chinese kiwifruit exports are also small compared to imports [4]. Chinese kiwifruit production accounted for 70% of the world's total production in 2019, but the import volume is still much higher than the export volume. In contrast, nearly 95% of kiwifruit produced in New Zealand are exported. Many factors have contributed to the above situation. Many factors have led to the above situation. One of the most important reasons is that the product characteristics of these new cultivars of kiwifruit, such as nutritional composition, are not clear, so the consumers' degree of understandingand trust is poor. Conversely, New Zealand's disclosure of the nutritional and functional properties of new commercial cultivars [5; 6; 7; 8] promoted its successful commercialization and increased consumer acceptance. Therefore, fully studying the product characteristics and other indicators of the new cultivars of kiwifruit bred in China will be expected to provide help for the commercialization of new kiwifruit cultivars in China and provide more resources for consumers to purchase kiwifruit. In recent years, new kiwifruit cultivars widely accepted by consumers have shown high-quality flavor characteristics, indicating that taste (sweetness and acidity) and aroma are the basic characteristics affecting the fruit market and consumer acceptance. Aroma characteristics are among the most important organoleptic characteristics for kiwifruit quality and are the main concern to consumers. Thus, research on the aroma of kiwifruit has gradually gained attention, and an increasing number of researchers have studied the aroma characteristics of kiwifruit. At present, research on the aroma characteristics and composition of kiwifruit is mainly based on GC-MS [9], E-nose [9], and GC-O (gas chromatography-olfactory) [10]. [PERSON] et al. [9] traced the internal quality and aroma of Hongyang during ripening by means of GC-MS and E-nose. The unique aroma components of different species of kiwifruit were summarized by studying the aromas of Cuiyu (_A. deliciousa_), Jintao (_A. chinensis_), and Tuguomaohua (_A. eriantha_) varieties, but with only one sample per species [11]. The aroma components of kiwifruit \"Jecy Green\" [12], the aromas of Hayward and Hort16A [13], and the aroma characteristics of four yellow-fleshed kiwifruits and two green-fleshed kiwifruits (both _A. chinensis_) [14] were also analyzed or reviewed. Overall, in these previous studies, the aroma of kiwifruit is understood in some detail, yet further research is still required.