Assessing the impact of different cooking methods on nutrients, phytochemicals and antioxidant activity of traditional food plants

Abstract

Indigenous communities rely on various nutrient-dense traditional food plants (TFPs) to make traditional ethnic foods. The dietary potential of the nutrient-dense and healthy TFPs needs to be fully explored. This work investigates the proximate components, minerals, phytochemicals, and antioxidant activity of raw and cooked samples of five TFPs consumed by local communities in Kerala, India. The results show that Boerhavia diffusa possessed the highest fat (9.02 %) and fibre (3.61 %), whereas Ipomoea batatas recorded the highest protein (9.47 %), vitamin C (8.58 µM/g) and polyphenol (120.36 mg GAE/gDW) content. Amaranthus viridis showed an abundance of Mn (48.4 mg/100 g), Mg (2404.37 mg/100 g), and Zn (248.27 mg/100 g). The highest antioxidant activity was observed in A. viridis (IC50 = 0.426 mg/mL) and I. batatas (IC50 = 1.30 mg/mL) in the ABTS and DPPH assays, respectively. Boiling was the most effective cooking method for preserving protein, carbohydrate and fat stability in all TFPs. The TFPs showed a minimal reduction in minerals after being subjected to cooking. Microwaving had the least deleterious effect on phytochemicals in all TFPs. The research highlights the capacity of these TFPs to improve nutrition and promote consumer well-being with minimal environmental impact.