Changes in apple tissue with storage time: Rheological, textural and microstructural analyses

Abstract In this study, two varieties of apples with different textural characteristics—“Granny Smith” and “Golden Delicious”—were chosen to evaluate the efficacy of rheological and textural analyses. Dynamic rheological measurements (using a controlled stress rheometer), large deformation texture analysis (uniaxial compression and penetration, using a TAXTplus) and cryo-scanning electron microscopy were used to study the macro- and microscopic changes in apple tissue structure during 14 days of storage at 20 °C. The results obtained showed that both dynamic small deformation and static large deformation tests may be used to monitor mechanical changes in apple tissues. Observation of apple flesh microstructure revealed many changes that could be related to macroscopic changes in texture and rheology. All samples with low storage modulus and Young’s modulus values had microstructural characteristics with some component of the textural unity (middle lamella, cell wall or cell membrane) affected, resulting in effects such as exudation, loss of cell material and cell separation.

[1]  Andrew M. Taylor,et al.  Dynamic measurement of tissue rigidity during freezing and cooking of vegetablesa , 1992 .

[2]  C. Wright,et al.  Measurement of firmness in carrot tissue during cooking using dynamic, static and sensory tests , 1992 .

[3]  Milly,et al.  Determination of Minimum Inhibitory Concentrations of Liquid Smoke Fractions , 2005 .

[4]  L. Gerschenson,et al.  Effects of processing on kiwi fruit dynamic rheological behaviour and tissue structure , 2001 .

[5]  H. Goff,et al.  Osmodehydrofreezing of apples: structural and textural effects , 1996 .

[6]  M. A. Rao,et al.  Review: Dynamic Rheological Behavior of Heated Potatoes , 2002 .

[7]  S. Alzamora,et al.  Viscoelastic behavior of melon tissue as influenced by blanching and osmotic dehydration , 2005 .

[8]  E. Llorca,et al.  The effect of calcium and cellular permeabilization on the structure of the parenchyma of osmotic dehydrated ‘Granny Smith’ apple , 2004 .

[9]  O. Martín‐Belloso,et al.  Evaluation of Textural Properties and Microstructure During Storage of Minimally Processed Apples , 2003 .

[10]  J. Valle,et al.  Effects of blanching and calcium infiltration on PPO activity, texture, microstructure and kinetics of osmotic dehydration of apple tissue , 1998 .

[11]  H. Kunzek,et al.  Aspects of material science in food processing: changes in plant cell walls of fruits and vegetables , 1999 .

[12]  J. Abbott,et al.  Consumer evaluation and quality measurement of fresh-cut slices of ‘Fuji,’ ‘Golden Delicious,’ ‘GoldRush,’ and ‘Granny Smith’ apples , 2004 .

[13]  E. Costell,et al.  Perception of mealiness in apples: a comparison of consumers and trained assessors , 1998 .