Professional paper
https://doi.org/10.33128/pc.23.3-4.6
Application of physical pre-treatment of abrasion in the plum drying process
Tvrtko Jelačić
; Hrvatska agencija za poljoprivredu i hranu, Centar za voćarstvo i povrćarstvo, Zagreb, Hrvatska
Jana Šic Žlabur
; Agronomski fakultet Sveučilišta u Zagrebu, Zagreb, Hrvatska
Verica Dragović-Uzelac
; Prehrambeno-biotehnološki fakultet Sveučilišta u Zagrebu, Zagreb, Hrvatska
Martina Skendrović Babojelić
; Agronomski fakultet Sveučilišta u Zagrebu, Zagreb, Hrvatska
Ante Galić
; Agronomski fakultet Sveučilišta u Zagrebu, Zagreb, Hrvatska
Sandra Voća
; Agronomski fakultet Sveučilišta u Zagrebu, Zagreb, Hrvatska
Abstract
Wax coating from the surface of the plum fruit skin is a key barrier to water loss during the drying process and it is necessary to remove it. Therefore, the aim of this study was to examine the impact of the application of different pre-treatments, i.e. chemical (using alkali solution), physical (using abrasion) and thermal (heated distilled water) on the drying time of plum fruits cv. 'President'. Also, the key factors of each pre-treatment varied, such as the temperature of the solution in the thermal pre treatment (22 and 60 °C), the concentration (0.5, 1 and 1.5% v/v) and the temperature (22 and 60 °C) of the alkali solution (KOH) in the chemical and time duration of abrasion (5, 10 and 15 min) in the physical pretreatment, while the influence of each pre-treatment was researched. According to the obtained results, chemical pre-treatment with alkali solution concentration of 1 and 1.5% temperature of 60 °C was most effective in shortening the drying time of plums, lasted only 27 hours, while only 2 hours longer (29 h) lasted the drying of plums pre-treated by abrasion of 15 min. Based on all mentioned, it can be concluded that the physical pre-treatment by abrasion is extremely effective in removing the wax coating thus affecting shortening the drying time of plum fruits, and it should be emphasized that the application of abrasive pretreatment significantly affects the reduction of environmental pollution, but also human health, given that there are no chemical residues that after application should be adequately disposed of, which can affect humans and environment.
Keywords
drying time; KOH treatment; physical treatment; thermal treatment; 'President'
Hrčak ID:
243688
URI
Publication date:
4.9.2020.
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