Effect of hot-air drying on drying characteristics and quality of tiger nut.

BACKGROUND

The delayed drying of newly harvested tiger nuts can lead to mold and rancidity. Timely drying is therefore important. However, few studies have analyzed the impact of hot-air drying on the quality of tiger-nut oil and starch, making it essential to establish optimal drying conditions.

RESULTS

The results showed that the drying temperature was the most important factor affecting the drying speed, followed by drying airflow rate and loading capacity. A logarithmic model can describe the hot-air drying process of tiger nuts. The oil yield of tiger nut was highest after drying at 60 °C, reaching 22.40%. Meanwhile, the starch extracted from after drying at 60 °C had the highest solubility and expansion rate, 4.77% and 9.74%, respectively. Starch has the highest viscosity after drying at 70 °C, and it forms gel easily after aging.

CONCLUSION

High-quality tiger nuts should be produced under optimal conditions: a hot-air drying temperature of 60 °C, an airflow rate of 1.0 m s, and a loading capacity of 100 g. The results of this study have practical implications for the effective drying of tiger nuts. © 2024 Society of Chemical Industry.