Tsopwo Zena C, Jiokap Nono Y
Department of Process Engineering, National Advanced School of Agro-industrial Sciences, ENSAI, Ngaoundere University, P.O. Box 455, Ngaoundere, Cameroon.
Department of Chemical Engineering and Environment, UIT, Ngaoundere University, P.O. Box 455, Ngaoundere, Cameroon.
Heliyon. 2024 Oct 15;10(20):e39389. doi: 10.1016/j.heliyon.2024.e39389. eCollection 2024 Oct 30.
This work aims to investigate the dynamics of water loss (WL) and solute gain (SG) during dehydration impregnation by immersion (D2I) and intermittent immersion (D3I). WL and SG of mango slices, 4 1 1 cm in size, during dehydration immersion impregnation (D2I) and dehydration impregnation by intermittent immersion (D3I) were determined at 35, 45 and 55 °C for 270 min. Mango slices were immersed in a hypertonic sucrose solution of (61.6 ± 0.2) °Brix at a ratio of 6 mL of hypertonic solution per gram of fruit. Five semi-empirical models, two of which have been modified, were used to study mass transfer during D2I and D3I, namely the Azura, Weibull, Crank, Modified Crank I, and Modified Crank II models. The equilibrium water loss ( ), the equilibrium solute gain ( ), the diffusion coefficient, and activation energy were determined using the Modified Crank II model which was the best of all the tested models. Equilibrium water loss during D2I decreased with increasing temperature, while during D3I it increased with temperature. The during D2I and D3I increases with temperature but was higher in D2I than in D3I. The average water diffusion coefficients were (6.02 ± 2.62) × 10 m s for D2I and (4.89 ± 0.55) × 10 m s for D3I and the average solute diffusion coefficients were (4.45 ± 0.53) × 10 m s for D2I and (8.33 ± 0.79) × 10 m s for D3I. The activation energies for WL in D2I and D3I were respectively 38789 J mol and 9503 J mol. The respective values for SG were 9037 J mol and 7327 J mol. This work demonstrates that mass transfers in D3I are better than those in D2I, and it highlights that, unlike the D2I process, the D3I process is less sensitive to temperature variations, making it particularly advantageous for processing products with high nutritional value.
本研究旨在探究浸没式脱水浸渍（D2I）和间歇浸没式脱水浸渍（D3I）过程中的水分损失（WL）和溶质增益（SG）动态变化。对尺寸为4×1×1厘米的芒果片，在35、45和55℃下进行270分钟的脱水浸渍（D2I）和间歇浸没式脱水浸渍（D3I），测定其WL和SG。将芒果片以每克果实6毫升高渗溶液的比例浸入（61.6±0.2）°Bx的高渗蔗糖溶液中。使用五个半经验模型（其中两个已修改）来研究D2I和D3I过程中的传质，即阿祖拉模型、威布尔模型、克兰克模型、修正克兰克I模型和修正克兰克II模型。使用所有测试模型中表现最佳的修正克兰克II模型来确定平衡水分损失（ ）、平衡溶质增益（ ）、扩散系数和活化能。D2I过程中的平衡水分损失随温度升高而降低，而D3I过程中的平衡水分损失随温度升高而增加。D2I和D3I过程中的 随温度升高而增加，但D2I中的 高于D3I中的 。D2I的平均水分扩散系数为（6.02±2.62）×10 米²/秒，D3I的平均水分扩散系数为（4.89±0.55）×10 米²/秒；D2I的平均溶质扩散系数为（4.45±0.53）×10 米²/秒，D3I的平均溶质扩散系数为（8.33±0.79）×10 米²/秒。D2I和D3I过程中WL的活化能分别为38789焦/摩尔和9503焦/摩尔。SG的相应值分别为9037焦/摩尔和7327焦/摩尔。本研究表明，D3I过程中的传质优于D2I过程，并且强调，与D2I过程不同，D3I过程对温度变化不太敏感，这使其在加工高营养价值产品时特别具有优势。
