Abstract:

Objective: To study the relationship between the composition and contents of high-molecular-weight glutenin
subunits (HMW-GS) and the dough rheological properties of steamed-bread flour. Methods: The HMW-GS composition
and contents of 16 kinds of steam-bread flour were determined by SDS-PAGE and gel imaging scanning, and the dough
rheological properties were measured by farinograph and extensograph. Results: The HMW-GS composition was 1, 7+8, 2,
7+9, 8, 5+10, and 2+12, as well as 8 combinations including (1, 7+8, 5+10), (7+8, 2, 5+10), (1, 7+8, 2, 5+10), (7+8, 2+12),
(7+9, 5+10), (1, 7+9, 5+10), (1, 7+9, 8, 5+10), and (1, 7+9, 8, 2, 5+10). An obvious positive correlation between the types
and contents of HMW-GS and dough farinograph and extension properties was observed, and the two dough properties
were influenced in decreasing order by (5+10), (7+8) and (7+9). In addition, the most significant positive correlation
existed between (2+12) content and dough extension properties. The presence of HMW-GS 1, 2 and 8 and combinations of
HMW-GS 2 with (5+10), 8 or (7+9) were better for both dough properties. Conclusion: The dough rheological properties of
steamed-bread flour are influenced by the kinds, contents and combinations of HMW-GS.

Key words: steamed-bread flour, high-molecular-weight glutenin subunits, HMW-GS composition and contents , HMW-GS combination, dough rheological properties