Gas chromatography–Olfactometry (GC–O)

The odor-active compounds were analyzed by OSME (Da Silva et al. 1994) using the SCDTI (time-intensity data collection system) data collection program (Da Silva 1999). The GC–FID was modified for the GC–O–OSME analysis according to Janzantti et al. (2012). Four trained and selected judges, 23–37 years old, were requested to appoint the intensity using the SCDTI scale and describe the odor of the passion fruit pulp from each stage of ripeness in triplicate. Data collected from the SCDTI software for each GC–O analysis session of each judge and each stage of ripeness were used to construct the individual aromagram, considering that peaks should be detected in at least two of three repetitions. Then, a consensual aromagram was constructed based on individual aromagrams, in which peaks should be detected by at least two of four judges. Description of each odor was established combining descriptions of all judges, and checked against literature (Acree and Arn 2004; Jordán et al. 2002; Janzantti et al. 2012; Janzantti and Monteiro 2014). Retention indices in the consensus aromagram were calculated to confirm that the chromatographic data and compounds identity were correctly related to the olfactometric data. The odoriferous intensity 4.0 or more, between terms “moderate” and “strong”, was of high importance, and those between 3.0 and 3.9, of moderate importance and between 0.1 and 2.9 of weak importance.