Evaluation of inverse configurations in plum dehydration ovens.

Abstract

Plum drying is usually carried out in gas dehydrators. There are two typical operations; parallel flow (PF) and counterflow (CF), being the second option the most common in Argentina. The objective of this study was to compare both operation methods under the same functioning conditions to analyze whether the change in logistics is justified. For this, residence times of the fruit within the dehydrator and temperature and humidity among the fruit were determined. The desired final weight reduction was achieved in equivalent times in both operations methods; therefore, an operation change would not be justified. In CF system there is a continuous increase of temperature and a continuous decrease of humidity among the fruit. While in PF, different stages or pulses can be observed in which the temperature is initially high and drops abruptly with the entry of a new car into the system, which also increases the humidity. The effect of variations of temperature and humidity within the system must be complemented with quality studies of the final product.