Buckwheat starch: structure, functionality and enzyme in vitro susceptibility upon the roasting process.
Starch of dehulled buckwheat grains with a moisture content of 14.5% before and after thermal treatment (160 degrees C/30 min) was used in this study. The crystal structure of buckwheat starch was of the A-type. The thermal process applied elicited slight changes both in infrared spectra and relative crystallinity on X-ray diffraction patterns. The scanning electron microscopy studies demonstrated polygonal and irregular shape of starch granules. After the thermal treatment, some breakings or conglomerates were noticed on the granules. The roasting process also affected a decrease in the swelling power and solubility. The release of glucose and changes in resistant starch after partial hydrolysis by pancreatic alpha-amylase and other intestinal enzymes were analysed as well. The scanning electron microscopy visualization indicated significant susceptibility of buckwheat starch at the beginning (0.5 h) and during 6 h in vitro amylolysis.
Christa
Karolina
K
Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, Division of Food Science, Department of Functional Properties of Food, Olsztyn, Poland. karolina@pan.olsztyn.pl
Soral-Smietana
Maria
M
Lewandowicz
Grazyna
G
D000688:Amylose / Q000032:analysis; D055598:Chemical Phenomena; D055050:Diet, Gluten-Free; D004043:Dietary Fiber / Q000032:analysis; D004044:Dietary Proteins / Q000032:analysis; D019612:Fagopyrum / Q000737:chemistry*; D005511:Food Handling; D055951:Functional Food / Q000032:analysis; D005947:Glucose / Q000032:analysis / Q000378:metabolism; D006358:Hot Temperature; D006868:Hydrolysis; D008855:Microscopy, Electron, Scanning; D055292:Pancreatic alpha-Amylases / Q000378:metabolism; D010938:Plant Oils / Q000032:analysis; D012639:Seeds / Q000737:chemistry*; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013213:Starch / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000648:ultrastructure; D000074242:Sunflower Oil; D014867:Water / Q000032:analysis; D014961:X-Ray Diffraction
D004043:Dietary Fiber; D004044:Dietary Proteins; D010938:Plant Oils; D000074242:Sunflower Oil; D014867:Water; D013213:Starch; D000688:Amylose; D055292:Pancreatic alpha-Amylases; D005947:Glucose