Armazenagem refrigerada de umbu (Spondias tuberosa Arruda Câmara): alterações das características físicas e químicas de diferentes estádios de maturação.

Abstract

In this work the physical and chemical alterations of half-ripe and ripe umbu were studied, during the storage under refrigeration of 5, 10 and 15°C and relative humidity varying from 90 to 95%, with the objective of verifying the time of useful life of the fruit during the storage period. The study of the storage was accomplished in two stages: 1) next to Juazeirinho-PB half-ripe and ripe fruits, they were selected, agreements with hipoclorito of sodium (20ppm) and conditioned in polystyrene recipients and covered by plastic films of PVC. Later on stored in cameras of refrigeration controlled to the temperatures of 5, 10 and 15°C (90-95% U.R.). They were made determinations of the diameters, volume, sphericity and specific mass of the half-ripe and ripe umbus in the beginning of the storage and to each 15 and 30 days; 2) The fruits picked in São Vicente do Seridó-PB were submitted to all the operations described previously, except the wash operation, that was accomplished with the fungicide product benomyl (lg/1). The storage periods in which determined the pH, acidity, total soluble solids, consistency and loss of weight of the fruits were: 0, 3, 6, 9, 12 and 15 days for the ripe umbu; and 0, 6, 12, 18, 24 and 30 days for the half-ripe umbu. The determinations of the total and reducing sugars were made in the beginning of the storage and at each 7, 14, 21, 28 and 35 days for the half-ripe umbu and 4, 8, 12 and 16 days for the ripe umbu. In agreement with the obtained results one can concluded that: a) The half-ripe and ripe umbus, conserved at temperature of 5,10 and 15°C, had a reduction in its medium diameter and in the volume, during the storage period. Due to this fact, alterations were observed in the sphericity and in the specific mass of the umbus; b) The largest weight losses and of consistency of the halfripe and ripe umbus, during the storage period, they were observed when conserved at temperature of 15°C; c) The coloration of the half-ripe fruits stored to the temperature of 10 and 15°C was altered in the first 15 days of storage, and to the temperature of 5°C the coloration was irregular indicating injury caused by the cold. The ripe fruits had small alterations in its colour, when submitted to the temperatures of 5, 10 and 15°C; d) The levels of pH, totals soluble solids and non-reducing sugars of the half-ripe and ripe umbus tend to decrease, and the levels of acidity of those fruits tend to increase, during storage period, for all the studied temperature; e) The sugars reducing of the half-ripe umbu increase to the 7 days of storage, and later of that period tend to stay constant, and in the ripe fruits tend to increase to the 8 days, decreasing soon after; f) The total sugars of the of half-ripe and ripe umbus tend to increase until the 14 and 8 days, respectively, decreasing soon after; g) The half-ripe umbus are conserved better to the temperature of 10°C, by a period of 30 days; h) The ripe umbus are conserved better of 5°C, with conservation possibility for a period of 15 days; i) The kinds of fungus identified in the of half-ripe and ripe umbus, during the storage period, were Colletrotichum, Cladosporium, Sphaceloma and Aspergillus, and the largest incidence of fungus happened at temperature of 15°C.