TITLE:
Estimation of Thermodynamic Parameters for Better Conservation of Fresh Tomato (Lycopersicum esculentum)
AUTHORS:
Clément Ahouannou, Codjo Goudjinou, Sibiath G. Osséni, Julien Adounkpe, Waliou Amoussa Hounkpatin, Basile Kounouhewa
KEYWORDS:
Tomato, Isotherms, Theoretical Trend Model, Thermodynamic Properties, Heat of Sorption
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.13 No.2,
April
21,
2023
ABSTRACT: Knowledge of the state of water balance of agro-food
products is an essential step in drying or
storage operations for preservation. Our study made it possible to
determine the thermodynamic parameters which influence the storage conditions
of fresh tomatoes grown in the south of Benin; and to predict its hygroscopic
behavior during post-harvest storage. The desorption isotherms obtained at 40℃,
50℃ and 60℃, by the static gravimetric method using saturated saline
solutions, are compared with those of the theoretical models of Brunauer, Emmet
and Teller (BET), SMITH, PELEG and Guggenheim-Anderson-Boer (GAB). An adjustment of the experimental
points, on the theoretical models, was made thanks to the numerical method
which exploits the fminsearch algorithm
under the MATLAB software, version R2018a. The GAB model at 50℃ faithfully reproduces the experimental desorption curves for water activities
from 5.5% to
82.3%. The net isosteric heat of sorption was determined using the
Clausius-Clapeyron equation, it increases when the degree of dehydration of the
product increases. The applied isokinetic theory and enthalpy-entropy
compensation are consistent.