Cooking Treatment Effects on Sugar Profile and Sweetness of Eleven-Released Sweet Potato Varieties

Abstract

Cooking can significantly alter sugar content of sweet potato roots. Sweet potato roots were processed using three different cooking treatments, with the aim of investigating the effects of these methods on sugar profile and sweetness levels. Significant contribution of the cooking treatment and genotype, and their interaction on levels of the sugars were also determined. Moreover, sugar values were converted to relative sweetness per sucrose equivalent. The results revealed that cooking treatment produced the highest effect on sugar except fructose. Variability due to the interactions was significant and ranged from 2.60% to 11.74%. Whilst sucrose was the predominant in the raw form, maltose increased dramatically during cooking. Sweetness level increased substantially upon cooking and was highly dependent on initial sugar content, amylase activity and cooking treatment. Thus, evaluation of sweetness levels in sweet potato clones should not only be on the uncooked samples but should take into account the cooking methods employed.