Effect of low-temperature storage time on rejected green banana for flour production

Banana (Musa sp.) crops have one of the greatest economic impacts in Colombia, with an estimated production of 2.2 million tons in 2019. The aim of this study was to evaluate the effect of three antibrowning solutions: S1 (citric acid), S2 (citric acid + ascorbic acid), and S3 (citric acid + ascorbic acid + sodium metabisulfite) on the color, moisture, aw, pH, and acidity characteristics of flour from rejected green bananas. No significant differences were found (P>0.05). The values of a* and b* in all samples were in the grey zone. L* and WI presented values close to 50, which could be defined as a flour in a medium range of clarity. The citric acid anti-browning solution was selected based on criteria such as cost and availability. The second part of the study assessed the effect of the storage time (1, 3, 5, 7, 9 and 11 days) at 7 °C on the color and texture of fresh bananas; and pH, instrumental, and sensory color of banana flour. There were differences noticeable for the human eye in the color (ΔE) of the peel from day 3 compared to day 1; while in the pulp, these changes were observed from day 7. Statistically significant differences in instrumental and sensory color properties of banana flour were observed after day 7 (P<0.05). The maximum storage time at 7 °C of fresh green bananas to produce banana flour should not exceed 7 days because color may be affected.