Identification of headspace volatile compounds from different pear (Pyrus communis L.) varieties.
Suwanagul, A.; Richardson, D. G.;
Acta Horticulturae Year: 1998 Issue: No. 475 Pages: 605-623 Ref: 30 ref.
1998
บทคัดย่อ
Eight pear cultivars - Bartlett [Williams' Bon Chretien], Packham's Triumph, Anjou [Beurre d'Anjou], Comice [Doyenne du Comice], Bosc, Seckel, Vicar of Winkfield and Forelle - were ripened optimally and volatile compounds from the dynamic headspace were collected and identified by GC/MS. Among 112 compounds identified from all cultivars, 47 compounds are reported the first time in pears. The volatile profiles of these 8 cultivars were characterized by compounds in groups of esters, alcohols, hydrocarbons, aldehydes and ketones. Esters of short- to medium-chain alcohols and their corresponding acids, with or without some degree of unsaturation, were present as a major group in all cultivars. Esters comprised 60-98% of total volatiles. Hexyl acetate represented the major ester in all cultivars except Bosc and Vicar of Winkfield, which produced butyl acetate as a major ester, and Seckel, which produced ethyl-2,4-decadienoate as the major ester. Decadienoate esters were detected in all cultivars, bu
t varied in amount and isomerization characteristics. Straight-chain alcohols with 2-8 carbons were present as the second largest group in the profile. Two isomeric forms (E,E and E,Z) of the sesquiterpene hydrocarbon, alpha -farnesene, were always present in the profiles but varied considerably in amount. A small number of aldehydes and ketones were also found in some cultivars but present in very small amounts. Among the cultivars studied, Comice had the highest rate of volatile production at 42 micro g/kg per 100 litres of air while Seckel produced the lowest at 0.7 micro g/kg per 100 litres of air.