Cold-induced sweetening development in Indian potato (Solanum tuberosum L.) varieties

Developing cold sweetening resistant processing varieties is one of the frontal areas of research all over the world. In India, first potato processing variety was released in the year 1998 and till 2005 three varieties have been developed. But, there is no information available regarding sugar accumulation response of Indian varieties to low temperature storage. Therefore, it is imperative to generate basic information on cold sweetening development in Indian processing varieties for the use of potato breeders. Development of cold-induced sweetening and its relation to phenolic content of the tuber was studied in three Indian potato varieties viz., Kufri Chipsona-1, Kufri Chipsona-3 and Kufri Jyoti. The reducing sugars decreased in initial phase of storage, followed by continuous increase to unacceptably higher levels after around two weeks of storage. The increase in reducing sugar contents took place subsequent to increase in sucrose content. The changes in phenol content were not in a fixed trend. The degree or number of folds increase in reducing sugar content was relatively less in Kufri Jyoti which contained highest phenol content among the three varieties investigated. It is suggested that development of processing varieties with higher anti-oxidant content and lower invertase activity may provide better cold-induced sweetening resistance.