Turgor Pressure Effects on Textural Behavior of Honeydew Melon

Melon samples were equilibrated with solutions of increasing mannitol concentration in the range 0.00 to 0.80 M for the purpose of evaluating turgor pressure through volume change measurement. Melon compression and relaxation behaviors were evaluated with an Instron Testing machine, and structural characteristics were observed through microscopy. Immersion in mannitol solutions affected tissue firmness, reducing its value in all studied cases. After plasmolysis and plasmotypsis, samples became less elastic and more viscous, and firmness reduced more than 50%. Textural parameters obtained and microscopy results indicated that, in general, fracture might be associated with cell-wall integrity, and residual relaxation force might be associated with tissue turgor pressure.