文档介绍：Starch granule size distribution and HMW-GS accumulation and their regulatory approaches in wheat grain
Jiang Dong
College of Agriculture
Nanjing Agricultural University
Outlines
Introduction to wheat quality
Starch granule size distribution
HMW-GS accumulation
Definition adopted from the Cereal Knowledge Bank (IRRI & CIMMYT
The quality of a wheat class is its suitability for a specific final product.
Attributes of the inherent quality :
position or quality (dough mixing tolerance, handling properties)
Starch properties (pasting viscosity, food texture)
Grain hardness
I Introduction to wheat quality
Specialty: strong gluten wheat
Hard endosperm
Strong gluten with good extensibility
High water absorption
Panned breads, Flat breads
Specialty: middle-gluten wheat
Medium hard endosperm
Medium gluten content and mellow gluten; very versatile in a wide variety of applications
Steam breads、Dumplings 、Noodles
Specialty: weak gluten wheat
Soft endosperm
Weak gluten
Low moisture, low impurity level
Pastries, cakes, cookies
Wheat kernel
Endosperm
makes up 83% of the kernel
Bran
makes up 14% of the kernel
Germ
makes up 14% of the kernel
Starch granule
Gluten protein
Water soluble
Gluten
Starch
Ratio of granule
size A and B
A:B 100:0
A:B 70:30
A:B 40:60
A:B 0:100
BEST
Special wheat flour
(11-13% protein, 14% water )
II. Starch granule size distribution
Multi-modal distribution of starch granule sizes in wheat vs. single-peak distribution in other crops
A-Wheat B-Barley
C-Potato D-Corn
Starch granule size in wheat grain
Concerns:
Different sizes of starch granules in relation to starch quality
Formation of starch granule size distribution
Starch granule size distribution as regulated by genotype and environment