Barley for Food and Health: Science, Technology, and Products

PASTA MADE WITH BARLEY FLOUR 165
Asian noodles. These barleys were roller-milled to produce fiber-rich fractions
with 22% β-glucans and average 34% TDF. The fractions consisted mostly of
irregularly shaped fragments of endosperm cell walls, which were porous in structure.
Noodle dough was prepared with 25% fiber-rich fraction and 75% wheat
flour. Inclusion of fiber-rich fractions increased all viscosity parameters of the
noodle dough, due partially to water-holding properties. Additional water was
required in doughs to attain proper consistency. All noodles with fiber-rich fractions
were darker than control wheat noodles and contained more brown specks.
Cooking time for both white and yellow noodles with fiber-rich fractions was
reduced by 50%. Cooked yellow noodles containing fiber-rich fractions had good
firmness and resistance to compression, whereas the white noodles with fiber-rich
fractions were less firm and less chewy. In vitro digestibility of barley noodle
starch indicated decreased glucose release, which suggests a low glycemic index
value. This same research group (Lagassé et al. 2006) investigated the Canadian
hulless barleys reported by Hatcher et al. (2005): genotypes with normal,
waxy, zero-amylose, and high-amylose starch. In the Lagassé study, barleys were
milled into flour and blended at 20 and 40% levels with wheat flour for preparation
of yellow alkaline noodles. All barley noodles processed normally, although
work input varied somewhat relative to barley starch type. As predicted, color
was affected negatively. The polyphenolic activity of the barley flours was measured
as a possible answer to color problems. All the barleys possessed higher
phenolic activity than that of the wheat flour. Barley may contain 1.2 to 1.5%
polyphenols, which cause discoloration in baked products (Quinde et al. 2004).
Texture of barley noodles was strongly affected by starch type. Noodles containing
high-amylose or normal starch had bite and chewiness equal to wheat
noodles, while waxy and zero-amylose types had lower texture quality. These
researchers concluded that white noodles made with 40% barley flour contained
over 2.0% β-glucan and offer a healthful choice to consumers. The color factor
represents another anomaly between health benefits and consumer preferences.
The presence of polyphenols provides additional health benefits, such as antioxidant
activity and prevention of cellular defects. Although there is a preference
for white color in noodles, health-conscious consumers may eventually accept a
darker color.
Although not a pasta, Chinese steamed bread is a popular food in Asia and
among immigrants in many parts of the world. As with other wheat-based products,
it contains less than desirable amounts of fiber. Newman et al. (1994)
prepared typical Chinese steam bread, substituting 10, 15, and 20% of the wheat
flour with barley flour. The flours were obtained by roller milling a hard white
winter wheat (MT 7811) and a waxy hulless spring barley (Merlin). The wheat
and barley flours contained 2.4 and 7.7% TDF and 13.2 and 10.3% protein,
respectively. When barley flour was substituted for wheat flour, farinograph
parameters were changed and the dough generally became weak, dough development
time became shorter, mixing tolerance index values increased, and dough
stability time became shorter. Water absorption time increased slightly with the
substitution of barley flour for wheat flour. Crumb texture and color decreased, but