Texture and structure of glucose-infused melon

Microscopic features, mechanical and thermal properties of osmotically dehydrated guavas

“…The microscopy techniques, such as light microscopy and scanning and transmission electron microscopy, have been successfully used to describe the structural changes caused by the processing of fruits and vegetables, showing good agreement with the texture characteristics of the products (Mastrá ngelo et al, 2000;Muntada et al, 1998;Sormani et al, 1999;Vidales, Castro, & Alzamora, 1998). However, as structural alterations are frequently associated with changes in the cell wall of plant tissues, an evaluation of the rheological properties and thermal characteristics of the cell wall material could also be used to improve the technology employed in fruit and vegetable processing and to produce products with better properties (Kunzek, Kabbert, & Gloyna, 1999).…”

“…These phenomena provoke changes in the structural characteristics of the vegetable tissue depending on the process conditions and product characteristics, reflecting in the textural properties of the product (Mastrá ngelo, Rojas, Castro, Gerschenson, & Alzamora, 2000;Muntada, Gerschenson, Alzamora, & Castro, 1998;Sormani et al, 1999).…”

“…Cell turgidity loss, deformation and/or cell wall rupture, splitting and degradation of the middle lamella, membrane lysis (plasmalemma and tonoplast), cellular collapse, plasmolysis and tissue shrinkage have been pointed out as the main effects of osmotic dehydration on the cellular structure of plant tissues (Alzamora, Gerschenson, Vidales, & Nieto, 1997;Lewicki & Porzecka-Pawlak, 2005;Mastrá ngelo et al, 2000;Nieto, Salvatori, Castro, & Alzamora, 2004;Quiles et al, 2004).…”

“…Microscopic studies have revealed an enhancement of cell cohesion and turgidity and an increase in cell wall integrity due to the application of calcium salts to osmotically dehydrated fruits, resulting in products with better texture characteristics (Mastrá ngelo et al, 2000;Pereira, Carmello-Guerreiro, Bolini, Cunha, & Hubinger, 2007). The action of calcium on the cellular structure can be explained by its effect on the pectin matrix present in the cell wall of plant tissues.…”

Mass transfer in osmotically dehydrated apple stored at temperatures above zero

“…An increase in temperature or concentration, under otherwise similar conditions, results in an increase in osmotic pressure gradient, resulting in an increased mass transfer and thereby higher values of effective diffusion coefficients (Mastrantonio, Pereira, & Hubinger, 2006;Mayor, Moreira, Chenlo, & Sereno, 2006;Rastogi, Raghavarao, & Niranjan, 1997;Sereno, Moreira, & Martinez, 2001). Influence of the main process variables, such as concentration and composition of the osmotic solution, temperature, immersion time, pre-treatment procedures, agitation, nature of food and its geometry, solution/sample ratio on the mass transfer mechanism and the product quality have been studied extensively (Aktas, Fujii, Kawano, & Yamamoto, 2006;Beristain, Azuara, Cortes, & Garcia, 1990;Contreras & Smyrl, 1981;Islam & Flink, 1982;Mastrángelo, Rojas, Castro, Gerschenson, & Alzamora, 2000;Mavroudis, Gekas, & Sjö holm, 1998;Pereira et al, 2004;Rastogi & Raghavarao, 1994). The models based on the Fick's second law do not necessarily simulate the osmotic dehydration process.…”