Abstract
The antioxidant activity (AA) and color degradation were monitored in tomato quarters (Rio Grande) during hot air drying in a cabinet drier at five temperatures (60, 70, 80, 90 and 100°C) at an airflow rate of 0.2 m/s and 20% relative humidity. AA values of fresh tomatoes determined by total phenolic content (TPC), FRAP and DPPH assays were 85.3 mg GAE, 26.2 µmol TE and 31.3 µmol TE/100g dm, respectively. Increasing drying temperature resulted in a reduction in Hunter Lab and a/b color values of tomatoes as well as their AA values. During hot air drying, the degradation of AA and color values of tomatoes followed a first-order reaction. Activation energy values for AA degradation determined by TPC, FRAP and DPPH assays were 24.36, 22.91 and 23.67 kJ/mol, respectively. High correlations were found among the TPC, DPPH and FRAP values and lycopene and β-carotene contents of tomatoes during hot air drying. Degradation kinetic data revealed that color values and tomatoes AA are susceptible to drying temperature.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have