POTATO GENETICS, CYTOGENETICS, DISEASE RESISTANCE, AND PRE-BREEDING UTILIZING WILD AND CULTIVATED SPECIES
Location: Vegetable Crops Research Unit
Title: Light-colored, Low Acrylamide Potato Chips
Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: March 19, 2010
Publication Date: February 1, 2011
Citation: Pudota, B., Wi, L., Bethke, P.C., Jiang, J. 2011. Light-colored, Low Acrylamide Potato Chips [abstract]. American Journal of Potato Research. 88:62-63.
Potato tubers are stored at cold temperatures to prevent sprouting, minimize disease losses and increase the marketing window. Cold storage also causes an accumulation of reducing sugars, a phenomenon referred to as cold-induced sweetening. Unacceptable, dark colored chips and fries are formed during high-temperature frying when reducing sugars in cold-stored tubers react with amino acids in a non-enzymatic Maillard reaction. These fried products also accumulate acrylamide, a toxin and potential carcinogen. The mechanisms regulating sugar accumulation in the cold are, therefore, of commercial interest, but remain poorly understood. Vacuolar acid invertase converts sucrose into reducing sugars during cold storage. We hypothesized that by suppressing invertase gene expression we could address simultaneously the cold-induced sweetening and acrylamide problems. An RNAi-based silencing approach was used to develop lines in which invertase gene expression was silenced either partially or completely. RNAi lines grown in the field or in greenhouses did not have obvious phenotypic abnormalities or negative effects associated with silencing of the invertase gene. Chipping experiments performed on RNAi lines stored for up to six months at 4 °C produced dramatically light-colored, industry acceptable potato chips after deep-frying. Potato chips from some lines had 15-20 fold less acrylamide than potato chips processed from control tubers after two weeks of cold storage.