Agriculture Reference
In-Depth Information
Developing test methods that allow quick, reli-
able evaluation of wheat functional properties
helps wheat exporters to meet customer require-
ments without having to control the entire crop
as a single-desk entity.
US SYSTEM OF WHEAT CLASSIFICATION
The US FGIS became an agency of the USDA
in 1976 under the US Grain Standards Act. In
1994, FGIS merged with the Packers and Stock-
yards Administration to form a new agency, Grain
Inspection, Packers and Stockyards Administra-
tion (GIPSA). This agency administers a nation-
wide system for offi cially inspecting and weighing
grain and other commodities. The Grain Stan-
dards Act requires, with few exceptions, offi cial
inspection and weighing of export grain sold by
grade. The GIPSA does not change the standards
each year to refl ect the fair average of the crop;
rather, standards remain fi xed until specifi cally
revised and are changed only after consultation
with grain industry stakeholders.
The US system divides wheat into eight broad
classifi cations for marketing effi ciency. The
classes represent several hundred wheat cultivars.
The US system does not regulate or control
release of new cultivars. Instead, the market at
large determines, by supply and demand, what
cultivars will be planted and harvested for sale.
Therefore, standards describe a class as distinct
and separate from other classes; but in the US,
a class can encompass multiple cultivars. The
highest value of a particular class at a given point
in time assumes no mixture, intentional or unin-
tentional, with another class. The six classes of
economic signifi cance are hard red winter (HRW),
soft red winter (SRW), hard red spring (HRS),
soft white (SW), hard white (HW), and durum.
To allow trade of devalued wheat classes that have
been mistakenly blended together or wheat of an
undetermined class, the standards also classify
wheat as mixed or unclassed.
FUNDAMENTAL WHEAT
CLASSIFICATION CRITERIA
All wheat classifi cations were originally derived
from observable physical distinctions present in
wheat. The most commonly used characteristic is
the color of the outer layers of the kernel, often
described as either red or white. The red descrip-
tion refers to the reddish brown color of the seed's
protective layers, referred to by millers as the
bran coat. The white description refers to the
yellowish tan color of the bran coat found in some
regions and classes; this color is genetically dis-
tinct from the more common color in red wheat
cultivars.
Another common observable characteristic is
the texture or hardness of seed, which often is
described as hard or soft. At extremes, this texture
difference is easily determined by bite. Though
hardly objective, this texture determination
method played a role in the early days of wheat
identifi cation.
Planting and growing cycles also are used to
identify wheat. Wheat is described as a winter
wheat if planted in late summer or fall and har-
vested in late spring or early summer, remaining
in the ground through the entire winter. Spring
wheat is planted in spring and harvested in late
summer or early fall. This general classifi cation is
most common in areas frequently subjected to
very harsh winters with extremely low tempera-
tures. Hard red spring (HRS) wheat is an example
of a US wheat class identifi ed by endosperm
texture (hard), color (red), and the planting and
growing cycle (spring). Wheat identifi cation and
classifi cation is approached slightly differently in
each major exporting country. A general overview
of some classifi cation factors can help us under-
stand what is available when buying wheat and
why millers around the world value some wheat
classes more than others.
Grade factors
Grading standards used in the US are shown in
Table 19.4. In the US system, grade or grade
requirements are determined based on grain when
it is free from dockage, which is all matter other
than wheat that has been removed with an
approved device according to FGIS instructions
(http://archive.gipsa.usda.gov/reference-
library/handbooks/equipment/apprlist-a.pdf).
