Free Amino Acids and Sugars in 15 Sweetpotato Genotypes: Effects of Curing and Storage on Acrylamide Formation in Fried Chips

The effects of curing and storage on sweetpotato composition and fried chip acrylamide content were investigated in 15 genotypes. Curing increased sugar contents, which altered chip color but did not increase acrylamide formation. After 2 months of storage, acrylamide increased in some genotypes; however, acrylamide formation in chips plateaued or decreased with extended sweetpotato storage. Free asparagine was most correlated with acrylamide content, accounting for 68% of the variation, while reducing sugars were in excess. In atypical sweetpotato genotypes with low reducing sugars, both reducing sugar and free asparagine contents were needed for acrylamide predictions. The sum of non-asparagine amino acids did not improve acrylamide predictions. However, individual amino acids were predictive, with serine, tyrosine, aspartic acid, and glutamine being positive predictors and glutamic acid, glycine, and alanine as negative predictors of acrylamide formation, suggesting that non-asparagine amino acids also impacted acrylamide formation. This provides targets for reducing sweetpotato acrylamide formation potential.