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Titre :
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Fractionation of high-amylose maize starches by differential alcohol precipitation and chromatography of the fractions
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Auteurs :
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J. Klucinec ;
D. Thompson
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Type de document :
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article/chapitre/communication
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Année de publication :
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1998
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Format :
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p. 887-896
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Langues:
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= Anglais
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Catégories :
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DOSAGE ET ANALYSE PHYSICO-CHIMIQUE
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Mots-clés:
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AMIDON DE MAIS
;
FRACTIONNEMENT
;
ANALYSE CHIMIQUE
;
ALCOOL
;
PRECIPITATION
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Résumé :
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Three high-amylose maize starches (HAS) and a common corn starch (CCS) were subjected to differential alcohol precipitation using isoamyl alcohol and l-butanol to obtain fractions designated as amylose (AM), amylopectin (AP), and intermediate material (IM). For each starch, IM had a blue value and an iodine binding wavelength maximum (lambda(max)) between the lambda(max) of the respective AM and AP. Size-exclusion chromatography (SEC) showed similarities in the AM from CCS and HAS. HAS AP had higher blue values and iodine binding lambda(max) values than CCS AP. SEC of the intact HAS AP and IM both showed large proportions of material eluting after the void volume (45-85%) when compared to CCS AP and IM. Chain length (CL) distributions of debranched AP and IM indicated that these fractions from each starch were highly branched, and that AP had a shorter average chain length than IM. Consequently, the differential precipitation behavior of the HAS AP and IM appears dependent on general branching structure rather than size.
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Source :
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Cereal Chemistry, vol.75, n°6
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