Water sorption, glass transition, and microstructures of refractance window- and freeze-dried mango (Philippine “Carabao” var.) powder

• Author(s) / Creator(s)

  • Caparino, O. A.
  • Sablani, Shyam S.
  • Tang, Juming
  • Syamaladevi, Roopesh M.
  • Nindo, C. I.

• Water sorption isotherms, glass transition, and microstructures of Refractance Window (RW)– and freeze-dried Philippine “Carabao” mango powders were investigated. Water sorption isotherms were developed by the isopiestic method, while thermal transition of the powders, at various water activities (a w = 0.11–0.86), was determined using differential scanning calorimetry (DSC). The sorption isotherms of RW- and freeze-dried (FD) mango powders exhibited a type III sigmoidal curve, showing higher and lower adsorption capacities above and below 0.5 a w , respectively. A significant difference (p < 0.05) in water content of RW- and freeze-dried mango powders for equivalent water activities was obtained above 0.5 a w . The onset glass transition temperature (T gi ) of RW- and freeze-dried mango powder solids decreased as the water content increased. There were no significant differences (p ≥ 0.05) in T gi of RW- and freeze-dried mango powder solids at constant water activities, except for a w = 0.86. Microscopic examination of mango powders indicated that freeze-dried mango powders exhibited greater surface area and porosity in comparison to RW-dried mango powders.

• Date created

  2013-01-01

• Subjects / Keywords

  • Scanning Electron Microscopy
  • Glass Transition Temperature
  • Freeze Drying
  • Water Adsorption
  • Mango Powder
  • Refractance Window Drying

• Type of Item

  Article (Draft / Submitted)

• DOI

  https://doi.org/10.7939/r3-q8tf-ca18

• License

  © 2013 Taylor & Francis Group. This is an Accepted Manuscript of an article published by Taylor & Francis in Drying Technology on 18 Nov 2013, available online: http://www.tandfonline.com/doi/abs/10.1080/07373937.2013.805143