Estimated shelf life of pupunha and tucumã flours

This study aimed to estimate the shelf life of pupunha (Bactris gasipaes Kunth) and tucumã (Astrocaryum vulgare Mart.) flours from family farming in northeastern Pará state, Brazil, by monitoring their physicochemical characteristics using the Accelerated Shelf-Life Test (ASLT) methodology. The pupunha and tucumã flours were subjected to controlled temperature (25, 35, and 45 °C) and humidity (80%) conditions. Moisture content (MC), water activity (Aw), total color difference (ΔE), and total carotenoid content (TC) were determined monthly over a period of 91 days. The pupunha and tucumã flours showed respective MC values of 9.86 ± 0.12% and 4.86 ± 0.15%; Aw values of 0.59 and 0.33; and TC values of 104.95 ± 4.78 and 346.45 ± 16.67 μg of β-carotene/g (dry-weight basis). The ΔE data indicate a significant increase between 33 and 61 days, with values greater than 5. Moisture remained within legal limits, while the other parameters varied significantly. Only the Aw and TC data fit the kinetic regression models, following zero-order and first-order kinetics, respectively. According to the models, water activity is the first parameter to impact the stability of the flours, exhibiting the lowest activation energy (Ea) values, whereas TC is more influenced by temperature increases, showing higher Ea values. It is estimated, therefore, that pupunha and tucumã flours can maintain their functional appeal as a source of carotenoids for approximately 172 and 287 days, respectively, when stored at 25 °C and 80% humidity.