Now, potatoes with low sugar content and longer shelf life

The Central Potato Research Institute (CPRI) in Shimla, the country’s only premier potato research institute, has evolved a new technology to prevent conversion of starch into glucose in low temperature conditions, like cold storages. Glucose level in potatoes increases substantially in low temperature, reducing its shelf life and rendering it inedible for diabetic patients.

The CPRI said sugar or glucose levels in potatoes will not rise with the use of this technology. The institute is also getting a patent for this technology, CPRI director Bir Pal Singh told Deccan Herald on Monday. The breakthrough, Singh said, has been evolved purely for commercial. Low-sugar potatoes with a longer shelf life was otherwise not possible, with sugar level rising in cold storages.

The technology raises the hope for potatoes sans sugar being available in markets, something which may bring smile on the faces of the potato-loving diabetic patients. Once the technology is implemented commercially, diabetics with a sweet tooth will possibly find sugar-free potatoes in the nearby vegetable store.  

CPRI sources say potatoes contain starch which turns into glucose. In freshly harvested potatoes, the starch content is low at about 1 per cent, but the level of glucose rises beyond 6 per cent in low temperatures. 

Singh said: “This is the first such technology in the country. This will be a boon for the processing industry. Starch in potatoes turns into sugar and this process is accelerated by an enzyme called invertase. We have silenced this process, in fact stopped it, so that the sugar levels don’t increase in potatoes.” 

The technology has “great cold chipping attributes,” which controls the rise of sugar level in potatoes. “Transgenic potatoes have reduced expression of the vacuolar and invertase gene resulting in cold induce sweetening resistant potato which is desirable for the processing industry. The breakthrough is an outcome of teamwork and five years of research,” Singh added.