Innovative food science & emerging technologies
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Keywords:
03 Chemical Sciences, 06 Biological Sciences, 09 Engineering, Food Science, 31 Biological sciences, 34 Chemical sciences, 40 Engineering
Abstract:
The inactivation kinetics of polygalacturonase (PG) in tomato juice was studied during thermal and high-pressure/thermal processing. In the temperature range of 55–70 °C the thermal inactivation of polygalacturonase in tomato juice followed a fractional conversion model, with a thermostable fraction of approximately 14%. Under conditions of combined high-pressure/thermal processing, 200–550 MPa/5–50 °C, PG inactivation presented first order kinetics. A mathematical model to describe the inactivation rate constant as a function of pressure and temperature was formulated. Industrial relevance: Polygalacturonase is responsible for the decrease of viscosity in tomato-based products. However, little research on thermal and high pressure/thermal inactivation kinetics of tomato Polygalacturonase has been reported. This research clearly shows that it is possible to selectively inactivate PG by high pressure/thermal processing without applying high temperatures. This leads to tomato-based products with improved functional properties while other quality attributes (color, flavor, nutritional value) are maintained.