title: Non-additive response of blends of rice and potato starch during heating at intermediate water contents: A differential scanning calorimetry and proton nuclear magnetic resonance study.
abstract: The impact of different hydration levels, on gelatinization of potato starch (PS), rice starch (RS) and a 1:1 blend thereof, was investigated by differential scanning calorimetry and related to nuclear magnetic resonance proton distributions of hydrated samples, before and after heating. At 20% or 30% hydration, the visual appearance of all samples was that of a wet powder, and limited, if any, gelatinization occurred upon heating. At 30% hydration, changes in proton distributions were observed and related to plasticization of amorphous regions in the granules. At 50% hydration, the PS-RS blend appeared more liquid-like than other hydrated samples and showed more pronounced gelatinization than expected based on additive behavior of pure starches. This was due to an additional mobile water fraction in the unheated PS-RS blend, originating from differences in water distribution due to altered stacking of granules and/or altered hydration of PS due to presence of cations in RS.
authors: Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, Box 2463, B-3001 Heverlee, Belgium. Electronic address: geertrui.bosmans@biw.kuleuven.be.
authors: Geertrui M
authors: GM
authors: Bosmans
authors: Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, Box 2463, B-3001 Heverlee, Belgium.
authors: Bram
authors: B
authors: Pareyt
authors: Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, Box 2463, B-3001 Heverlee, Belgium.
authors: Jan A
authors: JA
authors: Delcour
mesh_terms: D002152:Calorimetry, Differential Scanning / Q000379:methods*; D006361:Heating; D008279:Magnetic Resonance Imaging / Q000379:methods*; D012275:Oryza / Q000737:chemistry*; D011198:Solanum tuberosum / Q000737:chemistry*; D013213:Starch / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D013213:Starch
keywords: Blends; Gelatinization; Potato starch; Proton mobility; Proton nuclear magnetic resonance; Rice starch