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United States Department of Agriculture

Agricultural Research Service

Research Project: Host-Specific Molecular Genetic Tools for Development of Disease-Resistant Crops

Location: Crop Improvement and Genetics Research

Title: Dark side of reducing sugars. Sugar isn’t always desirable, at least not in potato processing

Authors
item McCue, Kent
item Novy, Richard

Submitted to: Spudman
Publication Type: Trade Journal
Publication Acceptance Date: June 14, 2013
Publication Date: July 26, 2013
Citation: Mc Cue, K.F., Novy, R.G. 2013. Dark side of reducing sugars. Sugar isn’t always desirable, at least not in potato processing. Spudman. July/August:30-31.

Interpretive Summary: The amount and types of sugars found in potatoes at harvest and after storage affect their processing quality. Undesirable darkening of chips or fries occurs when high sugar potatoes are processed. Low levels of reducing sugars and/or free asparagine in tubers also reduce acrylamide in processed potato products. Scientists in the Physiology and the Genetics and Breeding sections of The Potato Association of America, many of whom work for the Agricultural Research Service, have developed methods to reduce sugar accumulation and the resulting product darkening and acrylamide formation. These advances will mitigate the rejection of up to 15% potatoes at processing plants and ensure that levels of acrylamides in processed products remain below levels of potential concern for consumers.

Technical Abstract: Tools from basic research allow the application of precise breeding to tackle the problem of cold-induced sweetening (CIS). Reduction in reducing sugars has been achieved by inhibiting a number of the genes that have been found to be involved in sugar release. Indeed suppression of the vacuolar invertase, starch-related RI (a glucan, water dikinase), and the phosphorylase L genes by Potato Association of America (PAA) scientists and their colleagues have each been shown to reduce CIS. Similarly, inhibition of the genes involved in CIS has been found to positively correlate with reduced acrylamide formation. Potatoes that suppress genes involved in CIS with demonstrated reductions in acrylamide production are being introduced by the J.R. Simplot Company. PAA scientists in the Physiology and Breeding and Genetics Sections continue to seek ways to further improve CIS resistance and its associated benefits in the future.

Last Modified: 11/23/2014
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