Thermal properties of barley starch and its relation to starch characteristics.
Amylopectin fine structure and starch gelatinization and retrogradation were studied in 10 different barley cultivars/breeding lines. Clusters and building blocks were isolated from the amylopectin by α-amylase from Bacillus amyloliquefaciens and their structure was characterized. Gelatinization was studied at a starch:water ratio of 1:3, and retrogradation was studied on gelatinized starch at starch:water ratio of 1:2, by differential scanning calorimetry. Three barley cultivars/breeding lines possessed the amo1 mutation, and they all had a lower molar proportion of chains of DP ≥38 and more of large building blocks. The amo1 mutation also resulted in a higher gelatinization temperature and a broader temperature interval during gelatinization. Overall, small clusters with a dense structure resulted in a higher gelatinization temperature while retrogradation was promoted by short chains in the amylopectin and many large building blocks.
Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden.
Anna
A
Källman
Food Science Department, University of Guelph, Guelph, ON N1G 2W1, Canada.
Varatharajan
V
Vamadevan
Food Science Department, University of Guelph, Guelph, ON N1G 2W1, Canada.
Eric
E
Bertoft
Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden.
Kristine
K
Koch
Food Science Department, University of Guelph, Guelph, ON N1G 2W1, Canada.
Koushik
K
Seetharaman
Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden.
Per
P
Åman
Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden. Electronic address: Roger.Andersson@slu.se.
Roger
R
Andersson
D000687:Amylopectin / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D001467:Hordeum / Q000737:chemistry*; D013213:Starch / Q000737:chemistry* / Q000302:isolation & purification; D013696:Temperature; D000516:alpha-Amylases / Q000737:chemistry
D013213:Starch; D000687:Amylopectin; D000516:alpha-Amylases
Amylopectin structure; Barley; Gelatinization; Retrogradation; Starch