do Carmo Juliana Rodrigues, Corrêa Jefferson Luiz Gomes, Cruz Matheus de Souza, Martins Maria Júlia Neves, Sanches Marcio Augusto Ribeiro, Telis-Romero Javier
Department of Food Science, Federal University of Lavras, Lavras, Brazil.
Department of Food Engineering and Technology, São Paulo State University, São José do Rio Preto, Brazil.
J Sci Food Agric. 2025 Aug 26. doi: 10.1002/jsfa.70149.
Moisture sorption isotherms and thermodynamic parameters are essential for designing and optimizing food processing and storage systems. This study aimed to evaluate these characteristics in untreated and osmotically treated mango slices, using isomaltulose and sucrose as osmotic agents. Moisture sorption isotherms were determined at temperatures ranging from 313.15 to 353.15 K using the static gravimetric method. The net isosteric heat of sorption was calculated using the Clausius-Clapeyron equation, along with differential enthalpy, entropy, and Gibbs free energy.
The sorption isotherms exhibited type II and III behavior. Microbiological stability was maintained at equilibrium moisture content levels below 0.20, 0.15, and 0.20 kg water per kg dry matter for untreated mango and samples treated with sucrose and isomaltulose, respectively. In all cases, equilibrium moisture content decreased with increasing temperature. Among the models tested, the Guggenheim-Anderson-de Boer (GAB) model provided the best fit to the experimental data (R > 0.994, χ ≤ 6.9 × 10, RMSE ≤2.6 × 10). The isosteric heat and entropy values suggested that moisture-solid interactions resembled those of pure water at moisture levels above 0.35 kg water per kg dry matter. Gibbs free energy values indicated a non-spontaneous sorption process for untreated mango, whereas sorption in treated samples was spontaneous.
The enthalpy-entropy compensation analysis confirmed that sorption processes in all mango samples were enthalpy-driven. Isomaltulose-treated mango exhibited the highest affinity for water, as evidenced by the most pronounced thermodynamic property values, highlighting its potential as a functional osmotic agent in fruit dehydration. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
水分吸附等温线和热力学参数对于食品加工和储存系统的设计与优化至关重要。本研究旨在以异麦芽酮糖醇和蔗糖作为渗透剂，评估未处理和经渗透处理的芒果片的这些特性。采用静态重量法在313.15至353.15 K的温度范围内测定水分吸附等温线。使用克劳修斯 - 克拉佩龙方程计算吸附的净等量吸附热，以及微分焓、熵和吉布斯自由能。
吸附等温线呈现II型和III型行为。对于未处理的芒果以及用蔗糖和异麦芽酮糖醇处理的样品，微生物稳定性分别在水分含量低于每千克干物质0.20、0.15和0.20千克水时得以维持。在所有情况下，平衡水分含量均随温度升高而降低。在所测试的模型中， Guggenheim - Anderson - de Boer（GAB）模型对实验数据拟合最佳（R＞0.994，χ≤6.9×10，均方根误差≤2.6×10）。等量吸附热和熵值表明，在水分含量高于每千克干物质0.35千克水时，水分与固体的相互作用类似于纯水。吉布斯自由能值表明未处理的芒果吸附过程是非自发的，而处理后样品的吸附是自发的。
焓 - 熵补偿分析证实所有芒果样品中的吸附过程均由焓驱动。异麦芽酮糖醇处理的芒果对水表现出最高的亲和力，最显著的热力学性质值证明了这一点，突出了其作为水果脱水功能性渗透剂的潜力。©2025作者。由John Wiley & Sons Ltd代表化学工业协会出版的《食品与农业科学杂志》 。
