Effect of thermal treatment on phytochemical constituents and anti-nutrients in herbal tea production from Coccinia cordifolia L.

This research was performed to evaluate the effect of thermal pretreatments including blanching (100°C, 5 s), microwaving (600 W, 5 min), steaming (100°C, 5 s); thermal treatments like sun drying (35 ± 0.5°C in 12 h), hot air drying (55 ± 0.5°C in 4 h), roasting (155 ± 0.5°C in 15 min) to the phytochemical compositions (total phenolic content, total flavonoid content, and total antioxidant capacity) and anti-nutrients (phytic acid content and tannin content). The dried herbal tea was sampled in two-day interval to monitor the retention of bioactive constituens, degradation of anti-nutrients and overall acceptance. Results showed that steaming (100°C, 5 s) and sun drying (35 ± 0.5°C in 12 h) were suitable for herbal tea production from Coccinia cordifolia leaf. This dried herbal tea was also stable for 6 months of storage.