## 1 Introduction  
Fruits contain various bioactive compounds, such as flavonoids, phenolic acids, carotenoids, vitamins and phytoestrogens, which endow fruits with strong antioxidant activity, reduce symptoms of metabolic syndrome and improve heart disease [1]. Fruits are commonly eaten fresh, while many fruits needed to be processed to extend their shelf life. At present, the main types of processed fruit products are wines, vinegas, dried fruits, canned fruits, jams and juices [2]. Juice is an important element of a healthy diet, supplying essential nutrients [3]. The common types of juices on the market mainly include concentrated fruit juice, water extract fruit juice, dehydrated fruit juice, fermented fruit juices, powdered fruit juice, and not from concentrated (NFC) juice [4]. NFC juices are products that are obtained by pressing fruit, separating the pulp and debris to the required level, and then sterilizing and packaging it into containers for consumer use [5]. Among these juices, NFC juice is the most popular among consumers due to its natural fresh appearance,texture, lack of food additives and flavor [6]. However, the main sources of NFC juices were only apples, grapes and oranges [5], which caused difficulties in meeting the increasing demands of consumers. Therefore, NFC juices for other fruits need to be developed.  
Pomelos, also known as pummelo (_Citrus grandis_ ([PERSON]), are one of the three original species of citrus in the _Aurantioideae_ subfamily under the _Rutaceae_ family. It originated in Southeast Asia and has been cultivated in China for over 3000 years [7]. Pomelos are rich in bioactive substances, with antioxidant capacities, inflammatory, anticancer and antibacterial properties and preventative abilities regarding cardiovascular disease and diabetes [8]. It had been reported that native pomelo cultivars include _cv._ Deep Red, _cv._ [PERSON], _cv._ [PERSON], _cv._ [PERSON], _cv._ [PERSON], _cv._ [PERSON], _cv._ [PERSON], _cv._ [PERSON], etc. [9]. According to previous research, the cultivars of fruits have a great influence on their physicochemical properties [10]; [PERSON] [11] found that the aroma-active compounds of fresh watermelon juice in five cultivars were significantly different. However, there are few studies about the effect of pomelo's cultivars on its physicochemical characteristics [12].  
Pomelo fruits are often consumed fresh or processed into juice, candy, jam, wine, and essential oils [13]. As an important value-added product, fruit juice is valued by consumers around the world. Among these fruit juices, grapefruit juice is one of the most common processed products of pomelo fruit, and is preferred by consumers because of its rich nutrients and unique taste [14], while other cultivars of pomelo juice are not commonly available on the market. It is well known that the active ingredients [10] and volatile compounds [15] are significantly varied with different fruit cultivars. [PERSON] et al. [16] also found that a significant difference in phenolic content was observed among seven different cultivars of strawberry juices. However, most studies of pomelo juice mainly focus on extending the storage life of pomelo juice by using sterilization technology [17] and debitering pomelo juice to increase its acceptability [18]. The effect of the pomelo cultivar on the quality of pomelo juice has been less reported [19]. In addition, the pulp content of juice also had a great influence on its quality [20]. [PERSON] et al. [21] suggest that the fig pulp content affects the antioxidant capacities of fig juices. Therefore, the aim of study was to evaluate the differences in physicochemical properties, functional characteristics, and volatile compounds in low pulp and high pulp pomelo juices of six cultivars.