Abstract:

A kinetic investigation of quality variations in fresh cherry tomato juice was conducted after thermal
pasteurization (85 ℃ for 15 min) and ultrasonic sterilization (200 W and 40 ℃ for 30 min). For this purpose, changes in
color, vitamin C and total plate count were measured at intervals during subsequent storage at 0, 4, 10, 15 or 20 ℃. The
results indicated that the color changed obviously with increasing storage time and temperature for both types of processing.
Based on the variation of vitamin C, the shelf life of pasteurized cherry tomato juice was 3.8–4 days longer than that of
ultrasonic sterilized juice at low storage temperatures (0–10 ℃). There was no obvious difference in shelf life based on total
plate count. The shelf life of cherry tomato juice at storage temperatures of 0–20 ℃ could be precisely predicted by the first
order reaction kinetic model describing the changes in total plate count. At low storage temperatures (0–10 ℃), 6–9 days
were proposed as the shelf life of ultrasonic sterilized cherry tomato juice, while 6–8 days were proposed as the shelf life of
thermally pasteurized juice.

Key words: kinetics, cherry tomato juice, pasteurization, ultrasonic sterilization, shelf life