Gene suppression can reduce cold-induced sweetening in potatoes
Preventing activity of a key enzyme in potatoes could help boost
potato quality by putting an end to cold-induced sweetening,
according to U.S. Department of Agriculture scientists. Cold-
induced sweetening, which occurs when potatoes are put in long-
term cold storage, causes flavor changes and unwanted dark
colors in fried and roasted potatoes. But long-term cold storage
is necessary to maintain an adequate supply of potatoes
throughout the year. Agricultural Research Service scientists
found that during cold storage, an enzyme called invertase
causes changes in potato sugars--more accumulation of sucrose
and a corresponding increase in the amount of glucose and
fructose in tubers stored at very low temperatures. At the ARS
Vegetable Crops Research Unit in Madison, Wis., plant
physiologist Paul Bethke, geneticist Shelley Jansky, and
technician Andy Hamernik used a recently developed technology to
show that decreasing the activity of invertase is