Thermal characterization of starch–water system by photopyroelectric technique and adiabatic scanning calorimetry

Autor: Alfredo Cruz-Orea, Jan Thoen, Peter Jamée, Mihai Chirtoc, El Hassane Bentefour, Guido Pitsi, Christ Glorieux
Rok vydání: 2003
Předmět:
Zdroj: Review of Scientific Instruments. 74:818-821
ISSN: 1089-7623
0034-6748
DOI: 10.1063/1.1519676
Popis: Starch is one of the most important carbohydrate sources in human nutrition. For the thermal analysis of starch, techniques such as differential scanning calorimetry have been extensively used. As an alternative, we have applied a photopyroelectric (PPE) configuration and adiabatic scanning calorimetry (ASC) to study the thermal properties of starch–water systems. For this study we used nixtamalized corn flour and potato starch with different quantities of distilled water, in order to obtain samples with different moisture content. By using PPE and ASC methods we have measured, for each technique separately, the heat capacity by unit volume (ρcp) at room temperature for a corn flour sample at 90% moisture. The obtained values agree within experimental uncertainty. By using these techniques we also studied the thermal behavior of potato starch, at 80% moisture, in the temperature range where phase transitions occur. In this case the PPE signal phase could be used as a sensitive and versatile monitor for ph...
Databáze: OpenAIRE