title: Determination of sugars, organic acids, aroma components, and carotenoids in grapefruit pulps.
abstract: The composition and content of sugars, organic acids, volatiles and carotenoids, in the pulps of six grapefruit cultivars, were examined by HPLC and GC-MS. The results showed that sucrose was the dominant sugar in grapefruit, making up 40.08-59.68% of the total sugars, and the ratio of fructose to glucose was almost 1:1. Citric acid was the major organic acid and represented 39.10-63.55% of the total organic acids, followed by quininic acid. The ratios of individual sugars and organic acids play an important role in grapefruit taste determination. Monoterpenes and sesquiterpenes were the predominant volatiles in grapefruit, in particular d-limonene and caryophyllene. Caryophyllene, α-humulene, humulen-(v1), β-linalool and tert-butyl 2-methylpropanoate are the characteristic aroma compounds of grapefruit. Although β-carotene is the primary carotenoid in grapefruit, the pulp color is mainly determined by the ratios of zeaxanthin, β-cryptoxanthin and lycopene. Our results provide the first complete chemical characterization of the taste, aroma and color of grapefruit.
authors.affiliation: College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400716, PR China.
authors.forename: Huiwen
authors.initials: H
authors.lastname: Zheng
authors.affiliation: College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400716, PR China.
authors.forename: Qiuyun
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Chongqing Nanshan Botanical Garden, Chongqing 400065, PR China.
authors.forename: Junping
authors.initials: J
authors.lastname: Quan
authors.affiliation: College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400716, PR China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zheng
authors.affiliation: College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400716, PR China; Key Laboratory of Horticulture Science for Southern Mountainous Regions, Ministry of Education, Chongqing 400715, PR China. Electronic address: xwp1999@zju.edu.cn.
authors.forename: Wanpeng
authors.initials: W
authors.lastname: Xi
mesh_terms: D000080462:Acyclic Monoterpenes; D002241:Carbohydrates / Q000032:analysis*; D002338:Carotenoids / Q000032:analysis*; D019343:Citric Acid / Q000032:analysis*; D032083:Citrus paradisi / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D000077276:Lycopene; D000081222:Monocyclic Sesquiterpenes; D039821:Monoterpenes / Q000032:analysis; D009812:Odorants / Q000032:analysis*; D012717:Sesquiterpenes / Q000032:analysis
chemical_list: D000080462:Acyclic Monoterpenes; D002241:Carbohydrates; D000081222:Monocyclic Sesquiterpenes; D039821:Monoterpenes; D012717:Sesquiterpenes; D019343:Citric Acid; D002338:Carotenoids; C042686:humulene; C018584:linalool; D000077276:Lycopene
keywords: Carotenoids; GC–MS; Grapefruit; HPLC; Organic acid; Sugar; Volatiles