Improving potato varieties for better potato chips

Potato tubers used to manufacture potato chips and fries must meet strict quality control guidelines. One of the most important of these is a requirement that fried products are uniformly light coloured after cooking.

Storing potatoes at low temperatures results in an accumulation of sugars. These sugars undergo chemical reactions during cooking that give rise to dark-coloured chips and fries that may contain a high amount of a compound found in carbohydrate-rich foods cooked at high temperatures. Health concerns have been raised about the consumption of this compound, called acrylamide.

According to scientists at the Inner Mongolian University, University of Wisconsin - Madison, and the USDA Agricultural Research Service, reducing the activity of a single protein allowed for low-temperature storage of potato tubers without an accumulation of sugars. This approach was used successfully with four potato varieties currently in commercial production. The research was funded by Hatch funds to J.J. L.W. and was partially supported by the Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China and National Key Technology R&D Program to R.F.Z.

In each case, when the targeted protein’s activity was greatly reduced, tuber quality after low-temperature storage was improved. This data defines a specific genetic target for improvement of potatoes that will benefit consumers and producers by improving tuber quality and healthiness of potato products.

Furthermore, spoilage-related potato waste will likely be reduced since the modified tubers could be stored at cooler temperatures than those from conventional potato varieties.

Greenhouse and field evaluations have indicated that this method does not have negative effects on plant growth and yield. However, large-scale field trials will be necessary to validate these initial observations, according to UW-Madison scientist Jiming Jiang.

Full results from this study can be found in the 2011 May-June issue of the journal Crop Science.