MOLECULAR-STRUCTURES OF SOME WHEAT STARCHES

Molecular structures of amyloses and amylopectins from three varieties of Japanese wheat, Chihoku, Horoshiri, and Norin-61, and two wheat cl asses, Australian standard white (ASW) and Western white (WW), were ch aracterized. WW amylose was the largest (number-average degree of poly merization ($$$) over bar dp(n), 1570) and Chihoku amylose was the sma llest (dp(n) 830). ASW and Chihoku amyloses had higher amounts of bran ched molecules (similar to 42% by mole) with lower average numbers of chains (($$$) over bar nc similar to 13), than those of others (simila r to 28% by mole, ($$$) over bar nc similar to 19). The structural fea tures of amylopectins by iodine affinity and chain-length distribution were also characterized by varieties and classes. The amylose content s of the starches were in the range of 21.7.27.4% for ASW and WW, resp ectively. A lower amylose content and a higher amount of the branched amylose molecule with a lower ($$$) over bar nc may produce better qua lity Japanese-type noodle.