Premium
Physicochemical Properties of Rice Starch Modified by Hydrothermal Treatments
Author(s) -
Shih F.,
King J.,
Daigle K.,
An H.J.,
Ali R.
Publication year - 2007
Publication title -
cereal chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.558
H-Index - 100
eISSN - 1943-3638
pISSN - 0009-0352
DOI - 10.1094/cchem-84-5-0527
Subject(s) - starch , differential scanning calorimetry , chemistry , hydrothermal circulation , swelling , food science , moisture , water content , viscosity , cultivar , amorphous solid , agronomy , chemical engineering , crystallography , materials science , organic chemistry , composite material , physics , geotechnical engineering , biology , engineering , thermodynamics
Rice starches of long grain and waxy cultivars were annealed (ANN) in excess water at 50°C for 4 hr. They were also modified under heat‐moisture treatment (HMT) conditions at 110°C with various moisture contents (20, 30, and 40%) for 8 hr. The modified products were analyzed by rapid‐viscosity analysis (RVA), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD). Generally, these hydrothermal treatments altered the pasting and gelling properties of rice starch, resulting in lower viscosity peak heights, lower setbacks, and greater swelling consistency. The modified starch showed increased gelatinization temperatures and narrower gelatinization temperature ranges on ANN or broader ones on HMT. The effects were more pronounced for HMT than for ANN. Also, the typical A‐type XRD pattern for rice starch remained unchanged after ANN or HMT at low moisture contents, and the amorphous content increased after HMT at 40% moisture content.