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ARS Home » Midwest Area » Madison, Wisconsin » Vegetable Crops Research » Research » Publications at this Location » Publication #343977

Research Project: Cranberry Field Research

Location: Vegetable Crops Research

Title: Reduce darkening of chips and fries

item Bethke, Paul

Submitted to: Common Tater
Publication Type: Trade Journal
Publication Acceptance Date: 8/1/2017
Publication Date: 9/1/2017
Citation: Bethke, P. 2017. Reduce darkening of chips and fries. Common Tater. 69(9):40-44.

Interpretive Summary:

Technical Abstract: Senescent sweetening is a genetically programmed, developmental response of potatoes that results in an accumulation of sucrose, glucose and fructose during the late storage period. Senescent sweetening is inevitable and irreversible, and thus limits the duration of storage for chip and fry processing potatoes. Research on senescent sweetening that used several cultivated varieties and genetically modified lines with reduced expression of the vacuolar invertase gene has increased our understanding of this economically important process. This research has confirmed earlier finding showing that senescent sweetening is strongly dependent on tuber concentrations of glucose and fructose. Tuber sucrose has a dual role, as a predictor of increased reducing sugar contents, and as a direct contributor to chip color darkening. Senescent sweetening was delayed but not prevented in lines of potato in which reducing sugar accumulation was significantly decreased by silencing of the vacuolar invertase gene using RNA-interference. These finding provide guidance to storage managers on how to anticipate senescent sweetening in chip and fry processing potatoes targeted for long-term storage.