Water Content-Water Activity-Glass Transition Temperature Relationships of Spray-Dried Borojo as Related to Changes in Color and Mechanical Properties

作者：Hicela Mosquera Luz; Moraga Gemma; Fernandez de Cordoba Pedro; Martinez Navarrete Nuria^*

来源：Food Biophysics, 2011, 6(3): 397-406.

DOI：10.1007/s11483-011-9215-2

• Powdered borojo
• Maltodextrin
• Sorption isotherms
• Glass transition
• Compression test
• CIEL*a*b* coordinates

The water content-water activity-glass transition temperature relationships of commercial spray-dried boroj powder, with and without maltodextrin, have been studied as related to changes in color and mechanical properties. The GAB and Gordon and Taylor models were well fitted to the sorption and glass transition data, respectively. The Boltzman equation adequately described the evolution of the mechanical parameter characterized in the samples with the difference between the experimental temperature and the glass transition temperature (T (g)) of the sample. The color of the samples showed a sigmoid change with water activity. The changes in the mechanical properties of boroj powder related to collapse development started when the sample moved to the rubbery state and began to be significant at about 10 A degrees C above T (g). The increase in the molecular mobility from this point on also favors browning reactions. Maltodextrin presence slows the caking kinetics but induces color changes to spray-dried boroj powder.

• 出版日期2011-9