Phase Transitions in the Starch−Water System Studied by Adiabatic Scanning Calorimetry

Abstract

We report high-precision measurements of phase transitions in the starch-water system by using for the first time adiabatic scanning calorimetry (ASC). Potato starch and nixtamalized corn flours were studied by this technique as a function of the moisture content. We calculated the percentage of gelatinized starch granules, as a function of the temperature, for both flours. For bi-phasic behavior in potato starch, at intermediate water contents, we propose an explanation based on previous hypotheses and on the experimental behavior as deduced from ASC measurements. ASC results suggest, in the case of nixtamalized corn flour, that uniform moisture is present in corn starch granules for all the considered moistures. A shift to higher temperatures of the peak temperature is observed when comparing the c(p)(T) curves with the classical DSC endotherms as measured for this flour. For both flours we estimated from the ASC results the melting temperatures of the starch granules, at zero moisture content, by using Flory's equation.

Monitoring cake baking by studying different ingredient interactions: From a model system to a real system

“…The gelatinization temperature depends upon the botanical origin of starch and on the amount of water present, pH, and types and concentrations of salt, sugar, fat and protein in the recipe. In addition, the degree of cross-linking of the amylopectin, the amount of damaged starch granules, amylose and amylopectin contents, as well as the derivatization technology used, can play a role (Cruz-Orea, Pitsi, Jam ee, & Thoen, 2002;Fredriksson, Silverio, Andemon, Eliasson & Aman, 1998;Hermansson & Svegmark, 1996;Ubwa, Abah, Asemave & Shambe, 2012). A study of the effect of moisture content on the thermomechanical behavior of concentrated waxy cornstarch/water preparations was carried out by Rol ee, Chiotelli, and Le Meste (2002).…”

Structural modifications and thermal transitions of standard maize starch after DIC hydrothermal treatment

“…Due to the semicrystalline structure of starch, two phase transitions are likely to occur during the thermal treatment of starch-water systems: the glass transition that concerns the amorphous phase (mainly the branching regions of the amylopectin and most of the amylose chains) and the melting of crystallites (formed by adjacent short chains of amylopectin intertwined into double helices). The melting of crystallites can be detected by X-ray diffraction patterns, and differential scanning calorimetry (Donovan, 1979, Biliaderis, Maurice & Vose, 1980Hoseney, Zeleznak & Lai, 1986;Garcia, Colonna, Lourdin, Buléon, Bizot & Ollivon, 1996;Cruz-Orea, Pitsi, Jamee & Thoen, 2002;Ratnayake & Jackson, 2007). The melting temperatures (T m ) of starch-water system strongly depend on the water content.…”

REVIEW: Molecular Interactions in Starch‐Water Systems: Effect of Increasing Starch Concentration

“…1). A single sharp endotherm is observed during heating at 25-100°C (Blanshard 1987;Tester and Morrison 1990;Garcia et al 1996;Jang and Pyun 1996;Sahai and Jackson 1999;Maruuf et al 2001;Cruz-Orea et al 2002;Spigno and Faveri 2004;Koroteeva et al 2007) and occurs at ≈60-70°C when starch is heated at water concentration of ≥170% db. This first peak is generally referred to as the G endotherm.…”

“…This first peak is generally referred to as the G endotherm. The G endotherm, if present, occurs at a constant temperature regardless of the amount of water present in the system (Blanshard 1987;Tester et al 1990;Garcia et al 1996;Jang and Pyun 1996;Sahai and Jackson 1999;Maruuf et al 2001;Cruz-Orea et al 2002;Spigno and Faveri 2004;Baks et al 2007). For the same starch, ΔH generally increases with increasing water content.…”