Location: Vegetable Crops Research Unit
Title: Starch granule amylose content is associated with resistance to cold-induced sweetening in potato Authors
|Fajardo, Diego -|
Submitted to: Journal of Food Science and Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 21, 2014
Publication Date: N/A
Interpretive Summary: When potatoes are stored at cold temperatures, they produce dark colored fries and chips. Breeders have developed varieties with the ability to produce light fry products when stored at cold temperatures. These varieties are said to be resistant to cold-induced sweetening. Breeders have focused on changing genes for enzymes that lead to the accumulation of sugars in the cold, the cause of the dark color. We have demonstrated that the composition of the starch is also associated with resistance to cold-induced sweetening. This can be another target of breeders aiming to improve resistance.
Technical Abstract: Cold induced sweetening (CIS) is the accumulation of reducing sugars in potato tubers due to cold storage. It is undesirable because it results in dark fry products. Potato varieties vary in resistance to CIS. Research efforts have focused on enzymes that contribute to the accumulation of reducing sugars. Our study evaluated the relationship between CIS and the source of reducing sugars, the starch granule. We found that that the amylose content in four CIS resistant clones was higher than that of five susceptible clones. Amylose content was influenced not only by variety but also storage, production year and field location. Environment interactions were not detected. In contrast, interactions among main effects (variety, location, and year) were observed for starch granule size. Starch granule size did not change during storage. No relationship was observed between CIS resistance and starch granule size.