Effects of Different Pretreatments on Hot Air Drying Characteristics, Nutrition, and Antioxidant Capacity of Tartary Buckwheat Sprouts

Abstract

In order to enhance the quality of hot air drying for Tartary buckwheat sprouts and minimize the loss of active substances, this research explored the impact of Color Protection(CP), Osmosis(OM), Blanching (BC), β-cyclodextrin (β-CD), and Ultrasound (US) in conjunction with hot air drying on the color, nutritional value, antioxidant properties, and other attributes of Tartary buckwheat sprouts. The findings revealed that as the drying temperature increased from 50 °C to 70 °C, the drying duration for Tartary buckwheat sprouts decreased across all treatment groups, leading to a higher dehydration rate. Treatments involving CP, US, and BC effectively reduced the drying time of Tartary buckwheat sprouts. Sprouts subjected to CP, β-CD, and US treatments exhibited elevated L* values and decreased a* values and displayed a more vibrant green color. When exposed to a hot air setting of 60 °C, the total flavonoid content in the CP, OM, β-CD, and US groups increased by 8.76%, 6.76%, 12.34%, and 4.25%, respectively, compared to the Control Group (CK). The application of the CP, OM, β-CD, and US treatments enhanced the sprouts’ ability to combat ABTS and DPPH free radicals. Notably, under hot air conditions of 60 °C, the β-CD treatment demonstrated the most effective quality preservation during the hot air drying process for sprouts. This study provides valuable insights into the drying behavior of Tartary buckwheat sprouts and offers guidance for optimizing the drying procedures in industrial settings. Tartary buckwheat sprouts contain a variety of polyphenols and have a high water content. The study of changes in active components such as polyphenols and their alteration mechanisms in Tartary buckwheat sprouts under different processing methods is particularly important for the development of sprout processing.