## 2 Results and Discussion
### Sensory Evaluation of Celery Samples
Throughout these experiments, these genotypes have represented the most significantly different genotypes for all sensory attributes as well as behaved consistently in terms of their volatile profile when grown in different geographical locations and across multiple years. For this reason, they were recommended as \"stable\" genotypes for fresh produce growers [9; 12; 13]. Genotypes 12, 22 and 12x22 were mostly associated with flavour and odour attributes including fresh fennel, coriander, and parsley and with most of the volatile compounds. Hybrid 25x12 expressed lower associations with these flavour attributes due to its lower relative abundance of monoterenes, sesquiterpenes and phthalides and low scoring by the trained panel (Tables 1 and 2). The grass odour observed in the hybrid 12x22 was inherited from its female parent genotype 12, both expressing high relative abundance in (\(Z\))- and (\(E\))-3-hexenol, (\(Z\))-3-hexenyl butanoate and (\(E\),\(Z\))-3,6-nonadienol acetate, compounds observed to express a fresh, grass-like odour. Whereas the fresh parsley odour observed in hybrid 22x12 was inherited from the female parent genotype 22, both expressing a high relative abundance of monoterene compounds also identified in fresh parsley including \(\alpha\)-pinene, camphene, \(p\)-mentha-2,8-diene and \(\beta\)-pinene [5; 42] (Table 2). Along with this, genotype 12 was positively correlated with soapy flavour and the associations to flavour and odour attributes, combined with the high abundance of many volatile compounds (Table 1) confirms that genotype 12 is very aromatic. On the other hand, genotype 25 expresses no close association with any of the flavour and odour attributes confirming the previous statement that this genotype is not aromatic compared to genotype 12 or 22. Similar odour and flavour characteristics of genotype 25 were displayed in hybrid 25x12 (Figure 2, Table 2). Figure 2: Principal component analysis of six celery samples showing correlations with volatile compounds and sensory profiling: (**A**) projection of the samples; (**B**) distribution of variables, sensory attributes are highlighted in red; (**C**) compound codes as appear in plot (**B**). In terms of the sensory attributes, grass odour and flavour and parsley flavour were positively correlated with genotype 12, 22 and their hybrids. Alcohols (A3, A4), monoterenes (M6, M11), sesquiterpenes (S13, S14) and phthalides (P3, P4) also displayed positive correlation with these samples and attributes. Fresh parsley odour and flavour that was scored highly in genotype 22 and hybrid 22x12 expressed a positive relationship with each other accompanied by; esters (E1, E2), monoterenes (M1-M4, M6, M8, M10, M12, M14, M20, M23-27), sesquiterpenes (S7-S9, S11, S13) and phthalides (P2, P3) (Figure 2). Many compounds displayed a positive correlation with fresh parsley which was expected due to similarities between the celery and parsley aroma composition. Genotype 25 and hybrid 25x12 displayed the lowest scores of fresh parsley aroma and flavour due to the lower relative abundance of these compounds that were identified (Table 1). The results presented in Tables 1 and 2 showed significant differences in the aroma composition and sensory characteristics between the parental genotypes and hybrids and inherited characteristics were observed between parents and their offspring. Whether these celery hybrids meet the desires of the consumer, if there is a more preferred hybrid and what are the drivers of preference in celery was determined through the completion of a consumer trial, whereby the consumer acceptability of these hybrids and parental genotypes was investigated.