Oven drying and hot water cooking processes decrease HCN contents of cassava leaves.

Area of Science:

• Food Science and Technology
• Toxicology
• Agricultural Science

Background:

• Cassava leaves are a vital food source in many regions, but contain toxic hydrocyanic acid (HCN).
• Processing methods are crucial for reducing HCN levels and ensuring food safety.
• Understanding thermal degradation kinetics of HCN is essential for effective detoxification.

Purpose of the Study:

• To investigate the impact of oven drying and hot water cooking on hydrocyanic acid (HCN) degradation in cassava leaves.
• To determine the optimal temperature and time for HCN removal during processing.
• To contribute to the development of safe cassava-based food products.

Main Methods:

• Physicochemical characterization of nine cassava leaf varieties from Brazil.
• Quantification of total and free hydrocyanic acid (HCN) content.
• Thermal degradation studies using oven drying and hot water cooking at various time intervals.

Main Results:

• Cassava leaves exhibited significant variations in total HCN (90.6–560.9 mg/kg) and free HCN (16.6–59.2 mg/kg).
• Both oven drying and hot water cooking effectively reduced total HCN after 180 minutes.
• Boiling showed a rapid decrease in HCN after 20 minutes, while drying was more effective for free HCN removal (74.1%-92.2% degradation).

Conclusions:

• Thermal processing, specifically oven drying and hot water cooking, significantly degrades HCN in cassava leaves.
• Processing parameters (time and temperature) influence the extent of HCN detoxification.
• These findings support the safe consumption of processed cassava leaves, particularly in regions where they are a staple food.