Sensory qualities and digestibility of traditional Chinese dried sweet potato prepared with different cultivars and the relationship with starch characteristics

Abstract

This study investigated the sensory qualities and digestibility of traditional Chinese dried sweet potatoes (Gān Shŭ Gān) and identified the impact factors. Dried sweet potatoes prepared with orange-fleshed cultivars, particularly cultivars Pushu32 and Yanshu25, were preferred for their reddish hue compared to those prepared with the yellow-fleshed reference cultivar Zheshu33. The dried sweet potato made of those cultivars also provided better sensory experience mainly due to their higher chewiness. The estimated glycemic indexes (eGI) of dried sweet potato samples ranged from 78.50 − 99.49, with the sample prepared with Pushu32 exhibiting the lowest value. Correlation analysis and principal component analysis based on starch characteristics indicated that higher amylose content resulted in better sensory experience and more amylopectin longer chains (DP ≥ 25) contributed to lower digestibility. Both of amylose and amylopectin longer chains in sweet potato starch favored the stability of the paste. Additionally, larger starch granules in sweet potato were also conducive to lowering the eGI in dried products. These findings provided helpful insights for selecting raw materials in dried sweet potato processing.

Keywords

• Dried sweet potato
• Starch characteristic
• Sensory evaluation
• Estimated glycemic index