Understanding starch gelatinization: The phase diagram approach

作者：Carlstedt Jonas; Wojtasz Joanna; Fyhr Peter; Kocherbitov Vitaly^*

来源：Carbohydrate Polymers, 2015, 129: 62-69.

DOI：10.1016/j.carbpol.2015.04.045

• Starch
• Gelatinization
• Microscopy
• Synchrotron X-ray scattering
• Calorimetry
• Phase diagram

By constructing a detailed phase diagram for the potato starch water system based on data from optical microscopy, synchrotron X-ray scattering and differential scanning calorimetry, we show that gelatinization can be interpreted in analogy with a eutectic transition. The phase rule explains why the temperature of the gelatinization transition (G) is independent on water content. Furthermore, the melting (M1) endotherm observed in DSC represents a liquidus line; the temperature for this event increases with increasing starch concentration. Both the lamellar spacing and the inter-helix distance were observed to decrease with increasing starch content for starch concentrations between approximately 65 wt% and 75 wt%, while the inter-helix distance continued decreasing upon further dehydration. Understanding starch gelatinization has been a longstanding challenge. The novel approach presented here shows interpretation of this phenomenon from a phase equilibria perspective.

• 出版日期2015-9-20