Evolution of the characteristics of the hackberry (Celtis australis L.) fresh flesh stored under refrigeration conditions

Abstract

The characteristics of the hackberry (Celtis australis L.) fresh flesh stored under refrigeration conditions during ten weeks have been investigated. The hackberries were harvested at maturity (October) in Moratalla (Spain). The flesh was obtained using a pilot scale rotational sieve. Sterile plastic containers of 150 grams were fully filled with the hackberry fresh flesh and stored at 5ºC. Three containers were sampled at time intervals (initial, 1, 2, 4, 6, 8 and 10 weeks). The following parameters were analysed in the samples of hackberry fresh flesh: physicochemical characteristics (pH, soluble solids, titratable acidity, colour, moisture and water activity) and the microbiology (bacteria, yeasts and moulds). The results indicated that the pH decreased from 6.7 (initial) to 5.1 (10 weeks) and the titratable acidity increased from 0.48 g ACA/100 g (initial) to 1.26 g ACA/100 g (10 weeks), while the other physicochemical characteristics were constants during the ten weeks of refrigerated storage. The microorganisms were the key factor to stablish the acceptability of the fresh flesh. There was only the growth of the aerobic mesophilic from 9.0 x 105 cfu/g (initial) to 3.5 x 107 (8 weeks) and 2.8 x 107 (10 weeks of refrigerated storage). These results are to be considered for the use of the refrigerated hackberry fresh flesh as a natural ingredient at both domestic and industrial level.