Cold sweetening diversity in Andean potato germplasm from Argentina

Abstract

BACKGROUND: Cold-induced sweetening (CIS) is the accumulation of sucrose and reducing sugars in potato tubers at low temperatures. This process is central for the potato processing industry. During potato chip and French fry production, reducing sugars participate in the Maillard reaction to produce dark pigmented products not acceptable to consumers. Andean potatoes (Solanum tuberosum Group Andigena) constitute an enormous wealth of potato germplasm that can contribute to increase genetic diversity in breeding programs of many traits, including CIS. RESULTS: We analyzed reducing sugar content and chip quality in freshly harvested and cold-stored tubers from 48 native accessions. Andean accessions showed high variation in reducing sugar content and were classified in three types of CIS responses: type I, reducing sugar content before and after 4°C storage was lower than the value required by industry; type II, reducing sugar content before storage was acceptable, but after 4°C storage incremented up to non-acceptable levels; and type III, reducing sugar content was unacceptable before and after storage. CONCLUSION: Five Andean accessions presented acceptable reducing sugar content and good chip quality before and after 4°C storage in a consistent manner throughout several experiments. These features make them a useful source for improving the potato industry.