Development of volatile compounds fingerprints by headspace‐gas chromatography‐ion mobility spectrometry in concentrated tomato paste and distillate during evaporation processing

Abstract

SummaryVolatile profiles of fresh tomato pulp, concentrated pastes and distillates during evaporation were analysed by headspace‐gas chromatography‐ion mobility spectrometry (HS‐GC‐IMS), and volatile fingerprints were established. Topographic plots showed ninety signal peaks, forty‐two peaks (monomers and dimers) for twenty‐five compounds were identified, including four alcohols, ten aldehydes, eight ketones, two esters and a furan. The fingerprints showed clear differences. After evaporation, phenylacetaldehyde, pentanal, 2‐pentanone, 3‐methylbutanal and benzaldehyde were newly detected in the concentrated pastes and distillates, while 2‐heptanol, octanal, isopropyl acetate and 2‐pentylfuran were no longer detectable. Prolonged evaporation caused volatile components in both pastes and distillates to decrease; most were evaporated into distillates, including all alcohols and esters, most aldehydes and some ketones. The fresh pulp, concentrated pastes and distillates were clearly distinguished by principal component analysis and hierarchical clustering analysis. This work provides a theoretical reference for tomato paste processing and the utilisation of distillate discarded.