ISHS Acta Horticulturae 318: II International Symposium on Specialty and Exotic Vegetable Crops
POSTHARVEST HANDLING AND STORAGE OF JICAMA ROOTS |
| Authors: | M. Cantwell, W. Orozco, V. Rubatzky, L. Hernández |
| Abstract:
Most of the jicama root (Pachyrrhizus erosus (L.) Urban) marketed in the U.S. originates in Mexico. Physical damage (scuffs, abrasions, cuts, cracks), decay (on physically damaged and weakened areas), and internal discoloration are common defects observed on roots at retail markets. These latter two defects are due to the chilling sensitive nature of the roots, which are often handled at low temperatures for short periods in mixed load shipments and storages. The objective of this study was to evaluate changes in jicama quality in relation to time and temperature of storage. Medium-sized roots were selected a commercial planting in Nayarit Mexico, and transported by air to the Mann Lab. After trimming, they were stored in nonhumidified chambers at 0, 5, 10, 12.5 and 20C for up to 1 month. Other roots stored at these temperatures were transferred to 20C after 1, 2, 3 and 4 weeks. Roots were evaluated for respiration and ethylene production rates, internal and external visual quality, decay incidence, and ionic conductivity of tissue discs. Roots could tolerate less than 1 week at 0C, 1–2 weeks at 5C, and more than 2 but less than 3 weeks at 10C before chilling symptoms appeared (decay, internal discoloration being the principal visual symptoms). Roots stored at 12.5C more than 4 weeks remained in excellent condition. Increases in respiration rates during storage and after transfer, and ionic conductivity measurements corroborated the visual quality and decay assessments. Upon transfer to 20C, chill-damaged roots showed an increase in respiration that did not subsequently decline to normal low levels (5–7 ml CO2/kg-h at 20C). | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
