VOLATILE AND SOME FRUIT QUALITY CHARACTERISTICS OF NEW PROMISING PEACH GENOTYPES

Peach breeding studies were initiated in 1998 to improve early cultivars for subtropical conditions and late cultivars for highland areas. 4 genotypes (RU-24, J-92, J- 28 and S-6) were selected and are currently in the process of being patented. The purpose of this paper was to evaluate these promising genotypes in terms of their volatile com- pounds using Headspace-Solid Phase Micro Extraction Mass Spectrometry (HS- SPME/GC/MS) techniques. Volatile compounds, especially esters, are the main contribu- tors to fruity and floral notes and pleasant fruit flavours. Esters comprised the majority of volatile compounds in all four peach genotypes, however the composition of volatile compounds differed among genotypes. J-92 contained the most esters, while Ru-24 con- tained the least. Ru-24, however, contained the highest levels of lactones, aldehydes, and total acids of the four genotypes tested. The S-6 genotype contained the most total alco- hols. Thus, the volatile composition and contents depended largely upon the peach genetic background. In addition to the volatile compounds, the highest fruit weight were detected in genotype Ru-24 and total soluble solids (TSS) was greatest in genotype S-6.