Moisture sorption isotherms of fresh and blanched pumpkin (Cucurbita moschata)

Author(s)

Molina Filho, Lucidio ^[1] ; Rebes Goncalves, Ana Karla ^[1] ; Mauro, Maria Aparecida ^[1] ; Frascareli, Elen Cristina ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Dept Food Engn & Technol, Inst Biosci Language & Phys Sci IBILCE, BR-15054000 Sao Jose Do Rio Preto, SP - Brazil

• Document type: Journal article
• Source: FOOD SCIENCE AND TECHNOLOGY; v. 31, n. 3, p. 714-722, JUL-SEP 2011.
• Web of Science Citations: 7

Abstract

Moisture desorption isotherms of fresh and heat blanched pumpkins ( Cucurbita moschata) were determined at three temperatures ( 30, 50 and 70 degrees C), using the standard, static-gravimetric method. The GAB, Oswin, BET, Halsey, and Henderson models were tested and, with the exception of the Henderson model, showed satisfactory fits to the experimental data. The GAB model was used to analyze the fitting ability to describe the isotherm type. The shape of the desorption isotherms of fresh and blanched pumpkin at 30 and 50 degrees C was intermediate to types II and III, and at 70 degrees C it was of type II for the blanched pumpkin and close to type II for the fresh sample. The influence of blanching on the decrease in equilibrium moisture was very small compared to the fresh samples and it was related to the loss of soluble solids during the pre-treatment. The isosteric heat of sorption measures indicated that a larger amount of heat was required to remove the water from the fresh samples than from the blanched ones. (AU)

• FAPESP's process: 07/00809-3 - Pretreatment effects on drying and physicochemical and sensory properties of pumpkin snacks
• Grantee: Ana Karla Rebes Gonçalves
• Support type: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 07/07586-0 - Evaluation of combined methods to obtain dehydrated papaya and pumpkin
• Grantee: Maria Aparecida Mauro
• Support type: Regular Research Grants