Effects of Thermal and High-Pressure Processing on the Antinutritive Constituents and Antioxidant Content of Trichosanthes lobata Roxb. (Cucurbitaceae)

Abstract

This study examined the effects of thermal and high-pressure processing (HPP) on the antinutritive constituents and antioxidant content of Trichosanthes lobata Roxb. Thermal treatment at 80°C and 90°C significantly (P ≤ 0.05) increased oxalate levels, while 100°C caused a significant reduction compared to the control. Tannins, cyanide, phytate, and saponins decreased significantly across all thermal treatments. HPP reduced all antinutrients (oxalates, tannins, cyanide, phytate, and saponins) more effectively than thermal processing. Antioxidant content declined with heat: lycopene dropped from 19.52 mg/100 g (control) to 13.08, 10.37, and 10.13 mg/100 g at 80°C, 90°C, and 100°C, respectively, while β-carotene and FRAP followed similar declines. Conversely, HPP preserved and enhanced antioxidant properties: lycopene increased slightly, β-carotene rose significantly at 300 and 350 MPa, and FRAP improved significantly across all HPP groups. Overall, thermal processing reduced antinutrients but compromised antioxidants, whereas HPP simultaneously lowered antinutrients and enhanced antioxidant activity, demonstrating its superiority for preserving the nutritional and functional quality of T. lobata.