四川地区琯溪蜜柚及其芽变品种的果实品质

为明确四川蜜柚风味物质组成和含量特征,了解其营养品质状况,为四川蜜柚果实评价与深加工提供参考依据,以四川地区主栽的琯溪蜜柚Citrus maxima(Burm.)Merrill]及其4个芽变品种(红肉蜜柚、三红蜜柚、红绵蜜柚和黄金蜜柚)为试验材料,测定蜜柚果实基本生理指标,利用高效液相色谱(high performance liquid chromatography,HPLC)技术测定糖酸、酚类物质和类胡萝卜素的组成和含量,并采用1,1-二苯基-2-苦基苯肼自由基清除能力(1,1-diphenyl-2-picrylhydrazy,DPPH)、铁离子还原力(ferric reducing/antioxidant power,FRAP)和2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸二铵盐清除能力(2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonic acid diammonium salt,ABTS)3种方法测定抗氧化能力,运用主成分分析对果实品质进行评价。结果表明,柠檬酸和蔗糖是琯溪蜜柚主要的有机酸和可溶性糖,没食子酸和柚皮苷是琯溪蜜柚主要的酚酸和类黄酮,番茄红素和β-胡萝卜素分别是红肉型蜜柚和黄肉型蜜柚的主要呈色色素。其中,三红蜜柚的色泽表现最好,其总黄酮含量为13.34 mg·g^-1,约为琯溪蜜柚的1.6倍,柚皮苷的贡献最大,为807.47 μg·g^-1,显著高于其他品种,抗氧化能力在5个品种中最强,DPPH和ABTS分别达133.04和5.92 μmol·g^-1,显著高于其他品种,主成分分析排名第1。黄金蜜柚的总糖含量最高,为10.20%,可滴定酸含量最低,仅为7.5 g·L^-1,与其他品种呈显著性差异;但黄金蜜柚汁胞粒化现象较为严重,且抗氧化能力最弱,主成分分析排名第2。综合比较评价结果显示,三红蜜柚和黄金蜜柚在四川产区综合品质较好,可为下一步品种选择与果实加工开发提供参考依据。

Fruit quality of Citrus maxima (Burm.) Merrill and its bud mutants varieties in Sichuan area

In order to characterize the quality of pummelo fruits in Sichuan area, and provide useful information for exploitation and utilization of these pummelo, composition and content of flavor compounds were analyzed. The basic physiology indexes of pummelo fruits were measured and evaluated. High performance liquid chromatography (HPLC) was employed to detect and analyze the sugars, organic acids and volatile compounds of five pummelo cultivars. In addition, 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH), ferric reducing antioxidant power (FRAP) and 2,2'-azino-bis (3-ethylebnzthiozoline-6)-sulphonic aciddiammonium salt (ABTS) methods were used to evaluate the antioxidant activities. The results showed that citric acid, sucrose, gallic acid and naringin were the major organic acid, sugar, phenolic acid and flavonoid of Guanxi Miyou, respectively. Lycopene and β-carotene were the main color of red-fleshed and yellow-fleshed pummelo. Among them, SanhongMiyou had the best color performance, its total flavonoid content was 13.34 mg·g^-1, which was about 1.6 times that of Guanxi Miyou, and the contribution of naringin was the largest, which was 807.47 μg·g^-1, significantly higher than other cultivars. SanhongMiyou had the highest score of principal component analysis (PCA), which had the highest content of total flavonoids than other cultivars,and had the strongest antioxidant capacity, the values of DPPH and ABTS were 133.04 μmol·g^-1 and 5.92 μmol·g^-1, respectively. HuangjinMiyou was rich in the content of total sugar (10.20%), its total acids content (7.5 g·L^-1) was lower than other four cultivars. However, it showed the more serious of granulation phenomenon and the weakest of the antioxidant capacity,andits score of PCA was the second. Comprehensivequality of SanhongMiyou and HuangjinMiyou in Sichuan areawere better than other three cultivars, which could be used as materials for the variety selection and functional processing of pummelo in Sichuan area.