2. INTRODUCTION
ļ¶ Barley is one of the worldās oldest domesticated
crops .
ļ¶ BARLEY ā HORDEUM VULGARE
ļ¶ It is the world ās FOURTH most important cereal
after rice , wheat , and maize.
ļ¶ Barley is one excellent source of B ā COMPELX
VITAMINS and MINERALS.
ļ¶ It is nutritionally poor due to low content of essential
amino acids like lysine and threonine
3. ļ¶ Barley genotypes have been classified as
hull less and hulled ones.
ļ¶ hulled barley contains 3-7 percent beta
glucans
ļ¶ hull less contains 16 percent beta glucans
CLASSIFICATION
o order ā Poales
o family -Poaceae
o genus āHordeum
o species - vulgare
5. ļ¶ In India , production is largely confined
to utter pradesh,punjab ,and Haryana.
ļ¶ In Haryana , barley crops cover 58000
hectares of land area and total yield is
160,000 tones.
6. Objectives of milling:
1.Absence of sprouting.
2.Absence of discoloration due to
weathering.
3.Freedom from fungal attack and insect
infestation and damage.
4.Soundness of appearance.
5.Absence of undesirable aroma or flavor.
7. ā¢ The harder types of barley is best for
milling purpose because the hull and bran
can easily be removed from endosperm by
superficial abrasion
ā¢ particle will retain the shape of the whole
grain.
ā¢ The softer grains are not better because
they would tend and fragments, leading to
a reduction in the yield of first quality
products.
9. 1.CLEANING
ā¢ Machines similar to those used for wheat cleaning,
ā¢ The process of cleaning barley depends on the load of
foreign materials that it contains.
ā¢ This operation aims to remove foreign materiel (sand,
stones, metal, insects,.).
ā¢ If the impurities are not eliminated, the quality of the
product will be affected. It is to note that the metallic
particles can damage machines.
ā¢ magnetic device, separator classifier, destoner, indented
separator, scourer with an aspiration channel, dust
collectors as filters
11. BLOCKING AND PEARLING
ļ§ The hull of the barley is strongly attached to the
pericarp.
ļ§ Both are abrasive process differing in the degree of
removal of superficial layers.
ļ§ Blocking: Removal of the weakest part of the husk from
the grain.
ļ§ Pearling: Removal of remaining of the husk and the
separation of the endosperm.
12. ā¢ The hull and aleurone layer of the barley is removed by
rubbing with mill stone or emery.
ā¢ Dehusked barley is pearled .
ā¢ After third pearling bran is almost removed along with the
aleurone layer.
ā¢ This product is graded and sold as āpot barleyā or āblocked
barleyā .
ā¢ After 5-6 pearling the resulted pearl barley is small round
and white .
ā¢ Pearled barley is usually used in soup making.
15. 4.ASPIRATION
ā¢ Aspiration of the pearled grain to removes the abraded
portion and cutting of the blocked barley into grits.
ā¢ The blocked barley is first cut into grits and the grits are
graded by size and then rounded in pearling machines.
5.BLEACHING
ā¢ Removal of aleurone layer ,it gives bluish color.
ā¢ Bleached with moisture and Sulphur dioxide.
ā¢ Blocked barley is fed into a vertical earthenware
cylinder. Into which steam and Sulphur dioxide are
injected.
16. ā¢ The quantities used are 1-2%of moisture
and0.04% of Sulphur dioxide
ā¢ Solution of sulphurous acid ,sodium
disulphide
ā¢ Optimum time is 20-30min .
ā¢ Barley is binned for 12-24 hours for
effective bleaching .
ā¢ Excessive quantities of Sulphur residue in
the final product should be avoided.
17. 6.POLISHING:
The pearl barley is polished on
machines similar to those used for pearling
but equipped with stones made of hard white
sandstone instead of emery composition. The
average yield of barley is 67% of the whole
barley.
18. Barley grits:
ā¢ Blocked barley cut into portions are called grits.
ā¢ They are rounded in pearling machines then polished.
Barley flour:
ā¢ Barley flour is milled from blocked and pearled barley.
ā¢ Machines same as that used for wheat mill.