Click on “Download PDF” for the PDF version or on the title for the HTML version. If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options. The glass transition temperature of frozen foods and its influence on stability during frozen storage: analysis in starch sugar systemsPublished by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: Paper number 026181, 2002 ASAE Annual Meeting . (doi: 10.13031/2013.9793) @2002Authors: Dr. FERRERO CRISTINA, Dr. ZARITZKY NOEMI Keywords: Glass transition temperature, starch-sugar systems, rheology, hydrocolloids
During frozen storage, food systems based on gelatinized starch undergo syneresis and texture changes
related to amylose and amylopectin retrogradation; these recrystallization processes can turn food products
unacceptable. By applying concepts derived from physico-chemistry of polymers to food systems, many diffusioncontrolled
deteriorative phenomena have been related to the glass transition temperature. More specifically, the glass
transition temperature of the unfreezable matrix, which contains maximum solute concentration (Tg), determines the
stability of frozen systems. Maintaining the storage temperature below Tg the diffusional deteriorative processes are
minimized because the frozen matrix is in the glassy state. The objective of the present work was to analyze the
influence of the simultaneous addition of sucrose and different hydrocolloids (1% xanthan gum, guar gum or sodium
alginate) on Tg, correlating microstructural changes to rheological behavior. Differential Scanning Calorimetry
determinations showed that sucrose leads to Tg values below 22oC.
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