Aroma Characteristics of Cold/Hot Tomato Paste and Their Relationships with Non-volatile Components

Tomato paste is an important condiment, which is popular among consumers due to its unique taste and flavor. In this paper, headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) technology was used to measure the composition and relative content of volatile flavor compounds in eight kinds of tomato paste produced by cold break (CB) and hot break (HB) methods. The odor activity value (OAV) was calculated to determine odor active compounds. The relationship between the odor active compounds and the contents of reducing sugars, organic acids, ascorbic acid and pectin were analyzed by principal component analysis (PCA) and correlation analysis. The results showed that there were significant (P<0.05) differences in the composition and relative contents of flavor compounds in CB and HB tomato pastes. A total of 61 volatile compounds were identified in 8 samples, including aldehydes, alcohols and ketones, and 22 compounds belonged to odor active compounds (OAV≥1). The composition and relative contents of volatile compounds in CB tomato paste were significantly higher than that in HB tomato paste. At the same time, CB treatment was beneficial to keep high reducing sugars and organic acids content in tomato paste but would lead to the decrease of pectin concentration. Notably, the CB and HB tomato pastes could be distinguished by PCA of odor active compounds. Pearson correlation analysis suggested that β-cyclocitral, phenylacetaldehyde, linalool, α-terpineol, damascenone, 2-pentylfuran, 2-isobutylthiazole showed strong correlation with non-volatile components, so it was speculated that there might be interactions between them.