Effect of genotype, raw-material storage time and cut type on native potato suitability for fresh-cut elaboration

The suitability for fresh-cut processing of three native colored-fleshed potatoes (i. e., Bruja, Michune roja and Michune azul) and one commercial non-colored-fleshed potato (i. e., Asterix) was investigated. The impact of the storage time of the raw material and the type of cut (i. e., cube and chip) was also examined. Fresh-cut potato from raw material stored 2 months at 12 degrees C and 90% relative humidity (RH) displayed 1 to 2.5 times higher respiration activity than potatoes stored 4 months under the same conditions. Lower CO2 emission was only observed when potatoes stored 4 months were used. Fresh-cut potato shelf life decreased (less than 23 d at 5 degrees C) due to microbial growth. Approximately 7 log cfu g (1) for mesophilic and psycrophilic bacteria and Enterobactericeae when potatoes stored 4 months were used. Microbial growth was higher in chips than cube. The native colored-fleshed potatoes were rich in polyphenols, and total antioxidant capacity is 1 to 2 times higher than that of commercial potato. Total polyphenol content was not affected by the storage time of the raw material and remained stable under storage at 5 degrees C. However, fresh-cut potato processed from raw material stored 2 months had 1.5 to 3 times more total antioxidant capacity than that processed from raw material stored 4 months. For both parameters, Bruja exhibited values approximately 60% higher. Although all the analyzed varieties were suitable for fresh-cut elaboration, Bruja and Michuoe roja displayed higher metabolic activity and susceptibility to microbial deterioration and browning. To guarantee fresh-cut potato quality, raw material should be maintained no longer than 4 months in storage. From this moment some quality parameters alterations, that limited the fresh-cut shelf life, begin to be observed. (C) 2017 Elsevier B. V. All rights reserved.