Effect of dynamic high-pressure microfluidization and thermal processing on quality and volatile components of NFC tomato juice

In this study, tomato juice was processed using both dynamic high-pressure microfluidization (DHPM) and thermal processing (TP) to investigate their effects on the quality and volatile components of not-from-concentrate (NFC) tomato juice. Both DHPM (400 MPa, 25 ℃) and TP (95 ℃, 3 min) achieved sterilization and improved the brightness of the juice. TP resulted in severe loss of ascorbic acid with only 49 % retention. Significant color change after TP (ΔE = 1.62), and severe browning. DHPM treatment and TP reduced the acidity of tomato juice by 26.67 % and 22.67 %, respectively. DHPM improved tomato juice stability, and the D [3,4] and turbidity of the tomato juice decreased from 98.1 to 21.2 μm and from 55.64 to 24.58 nephelometric turbidity units (NTU), respectively. The identification of volatile components in tomato juice by gas chromatography-ion mobility spectrometry (GC-IMS) showed that the content of 37 volatile components in tomato juice increased after DHPM treatment. The contents of 2-furanmethanol and 2-ethylpyrazine, the off-flavor compounds of the cooking flavor, increased more after TP. The characteristic aroma of tomato, 2-phenylacetaldehyde, increased after processing. The study results provide basic theoretical data for tomato juice processing.