An integrated material science and kinetic approach towards understanding the aging of Common beans during postharvest storage

Legumes, including beans are a highly nutritious food widely consumed in developing countries (as a staple) and are a growing part of diets in developed countries, and with the predicted world population growth are likely to become even a greater part of diets. Their full utilisation is nonetheless hampered by the development of a physiological defect (hard-to-cook defect) during prolonged storage at high temperatures and humidity (typical of (sub)tropical countries where legumes are widely cultivated and dry stored at ambient temperature). Defective beans typically require longer cooking times (associated with loss of convenience and nutritional value) to attain desired texture, which reducing consumer acceptability and resulting in post-harvest losses. To date, the cause of development of hard-to-cook defect is not clearly understood, with different mechanisms involving distinct bean components (including cell wall material, starch, lipids, proteins, phytates and phenols) suggested to play a role. This research therefore aims to explore the physical state and (bio)chemical reactions in beans stored at different conditions for distinct periods towards determining the rate controlling reaction(s) during storage for beans. Through a stepwise build-up of structural complexity, the role of each bean substructure (seed coat or cotyledon or both) as well bean structural components (polymeric and small molecules) will be investigated.