INFLUENCE OF STORAGE TEMPERATURE OF POTATOES ON ACRYLAMIDE FORMATION IN ROASTED DISHES

The reduction of Swiss consumers’ exposure to acrylamide due to its transformation in potato dishes is one of the most important challenges for the whole potato chain supply, agricultural research and food authorities. To prevent potential health risks for consumers, it is important to gain their confidence and to maintain the considerable value of potatoes in the human diet now and in the future. Suitable raw material for roasting and frying for the catering trade and households is a requirement. In Switzerland, ware potatoes (potatoes intended for consumption, rather than seed) are generally stored long-term at 4 to 5°C. Storage temperature strongly influences reducing sugars, identified as the most important precursors for acrylamide formation. We examined five varieties for the development of reducing sugars in tubers during storage and consequential acrylamide content in standardized prepared hash browns. Tubers from three locations were stored at 4 and 7°C from November to May with or without Chlorpropham (CIPC) application, respectively. On average, tubers of all varieties stored at 4°C contained 5 g reducing sugars per kg fresh weight, whereas sugar content of tubers stored at 7°C varied from 1 g per kg FW (+CIPC) to 1.4 g per kg FW (without CIPC). Désirée tubers contained four times more reducing sugars than Victoria tubers. Mean acrylamide concentration in hash browns, prepared with 4°C-stored tubers, was 1300 µg/kg compared to 324 µg/kg with 7°C-stored tubers. Hash browns of Désirée tubers contained three times more acrylamide than hash browns prepared from Victoria and Agria tubers. Results indicate that the varieties Agria and Victoria are well adapted for warmer long-term storage. These experiments may provide essential information for companies with storehouses, and for retailers, the catering trade, and consumers. Food authorities may recognize the effect of higher storage temperatures on acrylamide formation during frying. Recommendations on potato storage in households and for food preparation are important for consumer information campaigns. Supplying the catering trade and households with 7°C-stored ware potatoes is an efficient measure to reduce consumer exposure to potentially harmful acrylamide. Since October 2004, Swiss retailers have offered ware potatoes stored at higher temperatures. Food authorities have appreciated this adaptation in storage of ware potatoes.