Unifine mill
Encyclopedia
A Unifine mill is a single one-pass impact milling system which produces ultrafine-milled whole-grain wheat
flour
that requires no grain pre-treatment and no screening of the flour. Like the grist
or stone mills that had dominated the flour industry for centuries, the bran, germ, and endosperm elements of grain are processed into a nutritious whole wheat flour
in one step. Consumers had accepted whole wheat products produced by grist
or stone mills. The flour produced by these mills
was quite coarse as they included the bran
and the germ
elements of the grain
.
As the nutritional value of vitamins, micro nutrients, antioxidants, phytonutrients, amino acids, and fiber
, were completely or relatively unknown in the late 19th century, removing the bran and the germ with the roller mill
, invented at that time, was an attractive idea. With the elimination of the bran and the germ, the resulting “white” flour composed entirely of the endosperm
produced an appealing product that research has since proven to be nutritionally deficient: The endosperm contains less than half of the total minerals and B-vitamins of the wheat kernel. Perhaps as significantly is the lost total food value since the bran and germ represent 17% of the whole grain
, and the process of eliminating the bran and shorts in the roller mill typically yields only 70 to 75% of grain weight as flour product, thus significantly reducing the human food supply as well.
into a fine powder
by impacting a high speed flywheel
. It was hoped that the resulting flour, made up of smaller particles, would have baking
qualities similar to the white, refined flours produced by the roller mill
s, yet retaining all of the bran, germ and endosperm of the whole grain.
Following World War II, with England focused on rebuilding their shattered infrastructure, the Englishman John Wright eventually made his way to Pullman, Washington
. There he succeeded in enlisting engineers at the Division of Industrial Research at Washington State College (now Washington State University
) in the project. Following the development of a successful prototype
, the milling, baking, and consumer acceptance of Unifine products was studied and funding of the first generation of commercial-grade mills came from a grant from the Washington State Grange. This grant was made possible by a donation by the Secretary of the Washington State Grange, Leonard Fulton, who ultimately went on to operate the first unifine flour mill.
Upon discovering that these mills could not be patented, the college opted to register the name Unifine and authorized Fulton and his Fairfield Milling Company Inc. to begin distribution of the first commercial flour milled by the machine under the brand name Unifine in 1962. A second Unifine Mill began operation under the label Flour Girls in the late 1970s directed and funded by individuals that participated in the research and development of the mills at the college. The flour produced was used by home bakers to make light, whole wheat bread
without the dense texture of breads made from traditional whole wheat flours. During that era of simmering consumer interest in the nutritional merits of whole wheat flour, these mills realized modest but ultimately unsustainable success. After roughly twenty years, these companies ceased operations and a new generation of unifine flour mills began producing flour under the Azure Standard brand. These flours are now marketed throughout the greater Pacific Northwestern
section of the United States.
industry association reports an approximate doubling of the whole wheat flour production from 2003 to 2007. In another visible example, whole wheat bread
has reached approximate parity with white bread
as measured by slice volume in the United States; as of 2010, whole wheat bread narrowly surpasses white bread as measured by dollar volume.
Fortification of white flour whole grains are more nutritious than refined products and wheat is no exception. Whole wheat flour is more nutritious than refined white flour, although through food fortification
, some micronutrients are added back to the white flour (required by law in some jurisdictions). Fortified white wheat flour does not, however, contain all of the macronutrients, fiber, antioxidants, phytonutrients, and much of the protein
of the wheat's bran and germ. Whole wheat is a good source of calcium
, iron
, fiber, and other minerals like selenium
.
s have adapted to the demand for whole grain products and most commercial whole wheat flour is currently produced using this milling system. In this case, the bran and the germ are further processed and then blended back into the endosperm (“white” flour) that it was separated from in the first place. While doing so enables the flour mills to use their existing equipment, it is a complex process. The roller mill method usually requires ‘tempering’ the grain
before milling (raising the moisture content); in contrast, dry grain is milled in the case of the Unifine mill, which may account for the suggested decreased rancidity rates reported in Unifine flour.
, or producing mineral powder for the mining industry or large scale powder
-making that the roller mill
system dominates. However, in the agricultural industry, where all the nutritional elements of the soft raw materials are desired in the end product, pulverizing it into powder in a single pass by the Unifine Mill has proven to be cost effective and less invasive. In addition to grains, a variety of agricultural products have been efficiently processed using this method including legumes and grapefruit rinds
.
Whole grain
Whole grains are cereal grains that contain cereal germ, endosperm, and bran, in contrast to refined grains, which retain only the endosperm. Whole grains can generally be sprouted while refined grains generally will not sprout. Whole-meal products are made by grinding whole grains in order to make...
flour
Flour
Flour is a powder which is made by grinding cereal grains, other seeds or roots . It is the main ingredient of bread, which is a staple food for many cultures, making the availability of adequate supplies of flour a major economic and political issue at various times throughout history...
that requires no grain pre-treatment and no screening of the flour. Like the grist
Grist
Grist is grain that has been separated from its chaff in preparation for grinding. It can also mean grain that has been ground at a grist mill. Its etymology derives from the verb grind....
or stone mills that had dominated the flour industry for centuries, the bran, germ, and endosperm elements of grain are processed into a nutritious whole wheat flour
Whole wheat flour
Whole wheat flour is a powdery substance derived by grinding or mashing the wheat's whole grain. It is used in baking but typically added to other "white" flours to provide nutrients , texture, and body to the finished product....
in one step. Consumers had accepted whole wheat products produced by grist
Grist
Grist is grain that has been separated from its chaff in preparation for grinding. It can also mean grain that has been ground at a grist mill. Its etymology derives from the verb grind....
or stone mills. The flour produced by these mills
Mill (grinding)
A grinding mill is a unit operation designed to break a solid material into smaller pieces. There are many different types of grinding mills and many types of materials processed in them. Historically mills were powered by hand , working animal , wind or water...
was quite coarse as they included the bran
Bran
Bran is the hard outer layer of grain and consists of combined aleurone and pericarp. Along with germ, it is an integral part of whole grains, and is often produced as a by-product of milling in the production of refined grains. When bran is removed from grains, the grains lose a portion of their...
and the germ
Cereal germ
The germ of a cereal is the reproductive part that germinates to grow into a plant; it is the embryo of the seed. Along with bran, germ is often a by-product of the milling that produces refined grain products. Cereal grains and their components, such as wheat germ, rice bran, and maize may be used...
elements of the grain
GRAIN
GRAIN is a small international non-profit organisation that works to support small farmers and social movements in their struggles for community-controlled and biodiversity-based food systems. Our support takes the form of independent research and analysis, networking at local, regional and...
.
As the nutritional value of vitamins, micro nutrients, antioxidants, phytonutrients, amino acids, and fiber
Fiber
Fiber is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread.They are very important in the biology of both plants and animals, for holding tissues together....
, were completely or relatively unknown in the late 19th century, removing the bran and the germ with the roller mill
Roller mill
Roller mills use cylindrical rollers to grind all sorts of materials rather than crushing them or grinding them between stones such as in a traditional grains mill. Roller mills are usually used for industrial grain milling and for grinding gravel into smaller rocks or pulverizing them...
, invented at that time, was an attractive idea. With the elimination of the bran and the germ, the resulting “white” flour composed entirely of the endosperm
Endosperm
Endosperm is the tissue produced inside the seeds of most flowering plants around the time of fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein. This makes endosperm an important source of nutrition in human diet...
produced an appealing product that research has since proven to be nutritionally deficient: The endosperm contains less than half of the total minerals and B-vitamins of the wheat kernel. Perhaps as significantly is the lost total food value since the bran and germ represent 17% of the whole grain
Whole grain
Whole grains are cereal grains that contain cereal germ, endosperm, and bran, in contrast to refined grains, which retain only the endosperm. Whole grains can generally be sprouted while refined grains generally will not sprout. Whole-meal products are made by grinding whole grains in order to make...
, and the process of eliminating the bran and shorts in the roller mill typically yields only 70 to 75% of grain weight as flour product, thus significantly reducing the human food supply as well.
History
Development of the Unifine impact (one pass) milling system began in England in the late 1930s. The goal was to develop a simple, holistic system that would pulverize all the elements of the raw materialRaw material
A raw material or feedstock is the basic material from which a product is manufactured or made, frequently used with an extended meaning. For example, the term is used to denote material that came from nature and is in an unprocessed or minimally processed state. Latex, iron ore, logs, and crude...
into a fine powder
Powder (substance)
A powder is a dry,thick bulk solid composed of a large number of very fine particles that may flow freely when shaken or tilted. Powders are a special sub-class of granular materials, although the terms powder and granular are sometimes used to distinguish separate classes of material...
by impacting a high speed flywheel
Flywheel
A flywheel is a rotating mechanical device that is used to store rotational energy. Flywheels have a significant moment of inertia, and thus resist changes in rotational speed. The amount of energy stored in a flywheel is proportional to the square of its rotational speed...
. It was hoped that the resulting flour, made up of smaller particles, would have baking
Baking
Baking is the technique of prolonged cooking of food by dry heat acting by convection, and not by radiation, normally in an oven, but also in hot ashes, or on hot stones. It is primarily used for the preparation of bread, cakes, pastries and pies, tarts, quiches, cookies and crackers. Such items...
qualities similar to the white, refined flours produced by the roller mill
Roller mill
Roller mills use cylindrical rollers to grind all sorts of materials rather than crushing them or grinding them between stones such as in a traditional grains mill. Roller mills are usually used for industrial grain milling and for grinding gravel into smaller rocks or pulverizing them...
s, yet retaining all of the bran, germ and endosperm of the whole grain.
Following World War II, with England focused on rebuilding their shattered infrastructure, the Englishman John Wright eventually made his way to Pullman, Washington
Pullman, Washington
Pullman is the largest city in Whitman County, Washington, United States. The population was 24,675 at the 2000 census and 29,799 according to the 2010 census...
. There he succeeded in enlisting engineers at the Division of Industrial Research at Washington State College (now Washington State University
Washington State University
Washington State University is a public research university based in Pullman, Washington, in the Palouse region of the Pacific Northwest. Founded in 1890, WSU is the state's original and largest land-grant university...
) in the project. Following the development of a successful prototype
Prototype
A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
, the milling, baking, and consumer acceptance of Unifine products was studied and funding of the first generation of commercial-grade mills came from a grant from the Washington State Grange. This grant was made possible by a donation by the Secretary of the Washington State Grange, Leonard Fulton, who ultimately went on to operate the first unifine flour mill.
Upon discovering that these mills could not be patented, the college opted to register the name Unifine and authorized Fulton and his Fairfield Milling Company Inc. to begin distribution of the first commercial flour milled by the machine under the brand name Unifine in 1962. A second Unifine Mill began operation under the label Flour Girls in the late 1970s directed and funded by individuals that participated in the research and development of the mills at the college. The flour produced was used by home bakers to make light, whole wheat bread
Whole wheat bread
Whole wheat bread is a type of bread that is made using flour which is partly or entirely made from whole or almost whole wheat grains, see whole wheat flour and whole grain. It is one kind of brown bread. Synonyms or near-synonyms for whole wheat bread elsewhere in the world are whole grain bread...
without the dense texture of breads made from traditional whole wheat flours. During that era of simmering consumer interest in the nutritional merits of whole wheat flour, these mills realized modest but ultimately unsustainable success. After roughly twenty years, these companies ceased operations and a new generation of unifine flour mills began producing flour under the Azure Standard brand. These flours are now marketed throughout the greater Pacific Northwestern
Pacific Northwest
The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...
section of the United States.
The rise of whole wheat flour
Despite historical consumer preference for refined white flour, whole wheat flour products are ascendant largely due to changing consumer attitudes. The Whole Grains CouncilWhole Grain Stamp
The Whole Grain Stamp was created by the and a panel of scientific and culinary advisors in January 2005 as a visual marker to signal products that contain dietarily-significant amounts of whole grains...
industry association reports an approximate doubling of the whole wheat flour production from 2003 to 2007. In another visible example, whole wheat bread
Whole wheat bread
Whole wheat bread is a type of bread that is made using flour which is partly or entirely made from whole or almost whole wheat grains, see whole wheat flour and whole grain. It is one kind of brown bread. Synonyms or near-synonyms for whole wheat bread elsewhere in the world are whole grain bread...
has reached approximate parity with white bread
White bread
White bread is made from wheat flour from which the bran and the germ have been removed through a process known as milling. Milling gives white flour a longer shelf life by removing the bran which contains oil, allowing products made with it, like white bread, the ability to survive storage and...
as measured by slice volume in the United States; as of 2010, whole wheat bread narrowly surpasses white bread as measured by dollar volume.
Fortification of white flour whole grains are more nutritious than refined products and wheat is no exception. Whole wheat flour is more nutritious than refined white flour, although through food fortification
Food fortification
Food fortification or enrichment is the process of adding micronutrients to food. It can be purely a commercial choice to provide extra nutrients in a food, or sometimes it is a public health policy which aims to reduce numbers of people with dietary deficiencies in a population.Diets that lack...
, some micronutrients are added back to the white flour (required by law in some jurisdictions). Fortified white wheat flour does not, however, contain all of the macronutrients, fiber, antioxidants, phytonutrients, and much of the protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
of the wheat's bran and germ. Whole wheat is a good source of calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
, iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
, fiber, and other minerals like selenium
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
.
Industry response
Roller millRoller mill
Roller mills use cylindrical rollers to grind all sorts of materials rather than crushing them or grinding them between stones such as in a traditional grains mill. Roller mills are usually used for industrial grain milling and for grinding gravel into smaller rocks or pulverizing them...
s have adapted to the demand for whole grain products and most commercial whole wheat flour is currently produced using this milling system. In this case, the bran and the germ are further processed and then blended back into the endosperm (“white” flour) that it was separated from in the first place. While doing so enables the flour mills to use their existing equipment, it is a complex process. The roller mill method usually requires ‘tempering’ the grain
GRAIN
GRAIN is a small international non-profit organisation that works to support small farmers and social movements in their struggles for community-controlled and biodiversity-based food systems. Our support takes the form of independent research and analysis, networking at local, regional and...
before milling (raising the moisture content); in contrast, dry grain is milled in the case of the Unifine mill, which may account for the suggested decreased rancidity rates reported in Unifine flour.
Applications
The Unifine mill has not proven suitable for grinding harder materials such as gravelGravel
Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...
, or producing mineral powder for the mining industry or large scale powder
Powder (substance)
A powder is a dry,thick bulk solid composed of a large number of very fine particles that may flow freely when shaken or tilted. Powders are a special sub-class of granular materials, although the terms powder and granular are sometimes used to distinguish separate classes of material...
-making that the roller mill
Roller mill
Roller mills use cylindrical rollers to grind all sorts of materials rather than crushing them or grinding them between stones such as in a traditional grains mill. Roller mills are usually used for industrial grain milling and for grinding gravel into smaller rocks or pulverizing them...
system dominates. However, in the agricultural industry, where all the nutritional elements of the soft raw materials are desired in the end product, pulverizing it into powder in a single pass by the Unifine Mill has proven to be cost effective and less invasive. In addition to grains, a variety of agricultural products have been efficiently processed using this method including legumes and grapefruit rinds
Grapefruit
The grapefruit , is a subtropical citrus tree known for its sour fruit, an 18th-century hybrid first bred in Barbados. When found, it was named the "forbidden fruit"; it has also been misidentified with the pomelo or shaddock , one of the parents of this hybrid, the other being sweet orange The...
.