in partial fulf ililment of - tdl
TRANSCRIPT
USES OF GRAIN SORGHUM AS FOOD FOR HUMANS
by
ANGEU RATTAN BOREN, B.S. in H.E.
A THESIS
IN
FOOD AND NUTRITION
Submitted to the Graduate Faculty of Texas Technological College
in Pa r t i a l Fulf ililment of the requirement for
the Degree of
MASTER OF SCIENCE
IN
HOME ECONOMICS
Approved
Accepted
August, 1962
rrE)(AS TECHNOL,OGitCAL CQi^i^LikL LUBBCX:K. TEXAS
\ v _
2oS
T^ l<^LZ
"77c?. 3 3
ci<?A SL
ACKNOWLEDGIMTTS
Grateful acknowledgment is made to Dr. Mina W. Lamb for her
guidance during the writing of this thesis and to the other members
of my committee, Mrs. Vivian J. Adams and Mrs. Gladys K. Holden, for
their encouragement and assistance in reviewing the manuscript.
Those who furnished grain sorghum samples for examination are;
Dr. R. E. Karper, Texas Agricultural Experiment Station Number 8;
Texas Technological College, School of Agriculture; Grain Products,
Inc., Dodge City, Kansas; and Harvest Queen Mills, Plainview, Texas.
11
TABLE OF CONTENTS
Page
ACKNOWLEDGMENTS ii
LIST OF TABLES iv
LIST OF ILLUSTRATIONS v
Chapter
I. INTRODUCTION 1
Purposes 1
Definition of Terms 2
n . REVIEW OF LITERATURE U
Botanical Classification h
Origin and Hybridization h
Production and Economy 6
Nutritive Contribution 8
Commercial Utilization 11
Palatability and Acceptability as Human Food 13
III. EXPERIMENTAL DESIGN ll;
Overall Plan lU
Test Series 18
IV. RESULTS AND DISCUSSION 2^
Varietal Differences 2^
Influence of Mesh Size 29
Extent of Use in American Foods 33
V. CONCLUSIONS h3
LIST OF REFERENCES U6
iii
LIST OF TABLES
Table Page
1. U, S. Grain Sorghum Production, I961 7
2. Average Support Prices, I960 7
3. Composition of Three Leading Cereal Grains 8
h . Comparison of B-Vitamins of Grain Sorghum
with Com (p.p.m.) 11
5- Grain Sorghum Test Samples li;
6. Specifications for the Milling of Com Products 1$
7. Basic Quick and Yeast Bread Formulas 17 8. Modified Quick and Yeast Bread Formulas Using
Grain Sorghum 19
9. Vitamin Analysis of Three Grain Sorghum Samples 29
10. Penetrometer Test of Yeast Bread Ip.
11. Proposed Grain Sorghum Mix and Variations k2
Iv
LIST OF ILLUSTRATIONS
Figure Page
1. Comparison of Amino Acid Content of Grain Sorghum
with Com ie- 9
2. Evaluation Device for Scoring Breads l6
3. Experimental Design 21 U. Range and Distribution of Particle Sizes of Three
Grain Sorghum Sanples 31
5. Grain Sorghum Miiffins 3U
6. Grain Sorghum Griddlecakes 3U
7. Conventional Griddle-baked Tortillas (left) and Deep-Fat Fried Chips (right) Made with Grain Sorghum . . . . 3^
8. Maple Drop Cookies (left) and Peanut Butter Cookies (right) Made with Grain Sorghum 35
9. Grain Sorghum Yeast Bread 36
CHAPTER I
INTRODUCTION
Purposes
This study was undertaken (1) to leam something of the palata
bility, cooking qualities, and nutritive contributions of several
varieties of grain sorghum, (2) to ascertain what mesh size is the
most desirable in milled grain sorghums to be used in food products,
and (3) to determine to what extent grain sorghum may be substituted
acceptably for wheat in some quick and yeast breads common in American
diets.
The real values of a study such as this are twofold. First in
revealing the possibilities of using milled grain sorghum as a substi
tute for part or all of the wheat flour in some bread and cereal pro
ducts for the sake of variety or in the event of a shortage of wheat
due to population increases or possible failure of the wheat crop. The
second value of such a study is in determining the cooking qualities
and palatability factors which, in turn, could pave the way for investi
gations into the development of an inexpensive multipurpose food pro
duct to be made available to undernourished people in many parts of the
world. Whereas certain varieties of grain sorghum constitute a large
portion of the high-cereal diet of peoples living in parts of Africa,
Asia, and South America, there is little indication that the crop will
take the place of or substitute for a major part of the wheat used in
the United States and Europe. Two reasons for this are (1) public
preference for wheat in cereal or bread products which require the tena
cious protein natural to wheat for culinary success and (2) the con
tinued surplus production of wheat in this country.
1 The use of grain sorghum as food for human consunption has been
[mentioned (1, 2, 3, k) in relation to the potential development of new
market opportunities. Considerable research has been directed toward
the commercial use of bland flavored grain sorghum starch in gels,
pastes, and films (2, 5, 6). In view of the corresponding dearth of in
formation regarding the uses of grain sorghum in bread products common
to American households, the need for a study involving some newer varie
ties of grain sorghum and their possible use in foods for human consump
tion seems pertinent.
Definition of Tenris
"Grain sorghum," "sorghum," and "milo" are used to identify
grains of the species Sorghum vulgare. Clarification of terms is neces
sary because of the confusion surrounding popular nomenclature of grain
sorghums and other grains. Holden (7) states "maize" is commonly used
in the Southwest to designate certain types of grain sorghums, "Milo
maize" and "kafir corn" have long been used by farmers when referring
to grain sorghum (8). Synonums for leading varieties of grain sorghum
add to the problem, for example some of the synonymous names used for
the Shallu variety of grain sorghum are: "California Rice com, Cali
fornia wheat. Chicken com, Chinese Golden sorghum, Egyptian rice, Egyp
tian wheat, Mexican wheat, and Rice com" (9). Varietal names used in
this research are those furnished by the organization supplying the sam
ples of grain sorghum.
"Commercial hybrid" is the term used to designate hybrid varie
ties of grain sorghum in current commercial production.-'- These varie
ties are cultivated to produce maximum quantities of grain in a given
area. Volume is the major concern; when marketing under the present U. S,
government subsidy program the standards for payments are not based on
superior quality insofar as this particular grain is concerned.
"Expei^entaljgbr^^ will be used to identify hybrid varieties
of grain sorghum which are in the experimental stages of development
at Texas Agricultural Experiment Station Number 8, Lubbock, Texas.^
The purpose of such experimentation in hybridization is to irtprove pala
tability, seed size, nutritive contribution, and/or other characteristics
that will increase the usefulness of the grain sorghum in industry and
animal feeding.
"Mesh size" is used to designate the size of sieve-^ through which
will pass all, or practically all, of a sample of milled grain sorghum
(Table 6). Terms such as "fine meal," medium meal," "coarse meal," and
"flour" refer to mesh size (Table 5). "In any flour there is a range of
particle sizes. The range of particle sizes, and also the distribution
of particle sizes within this range, can be controlled to a considerable
extent by proper choice and use of grinding and sifting machinery."^
• Term suggested by Jack King, Texas Agricultural Experiment Station, Number 8, Lubbock, Texas, during telephone conversation July 11, 1962,
^Ibid.
^United States Bureau of Standards.
^Letter from Dr. E. S. Stickley, Technical Director, Grain Products, Inc., Dodge City, Kansas, March 23, 1962.
CHAPTER n
REVIEW OF LITERATURE
Botanical Classification
Sorghum belongs to the family Graminae, tribe Andropogonae. All the annual sorghums have 10 pairs of chromosomes and belong to one specigs. Sorghum yulgare, which includes such diverse types as grain sorghums, sudangrass, broomcom, and tall sorghums that may be grown for forage, silage, or syrup.
Sorghum is a coarse grass that may grow from two to more than 1$ feet in height; the height of the widely cultivated varieties is usually between 2 and 5 feet. The stems are similar to those of com; they may be fairly fine in grass sorghums or more than an inch in diameter in some grain and forage types. Some varieties of grain sorghum have juicy stalks and leaf midribs while others are dry and pithy. The leaves are smooth and have a waxy surface; the leaf structure is such that water loss is reduced to a low figure. The inflorescence is a loose to dense panicle that may bear as many as 2,000 seeds. The seed of different varieties varies greatly in size, pigmentation and other characteristics (U).
Origin and ydridization
Carvings depicting sorghum plants in ancient Assyrian ruins in
dicate the grain was known as early as 700 B.C. (10). While sorghum is
believed to have originated in Africa a similar grain is cultivated in
central, western and northern China and Manchuria where it is known as
kaoliang; in India sorghum is among the chief food crops and is called
jowar or cholan; African varieties are named kafir (11). Kramer (U)
states that sorghum is the world's third most important food grain, ex
ceeded only by wheat and rice. Indeed, while it is the chief food grain
in much of Africa, India, and China which are arid areas where other
grains are not available, sorghum also is grown in Asia Minor, Iran,
Turkestan, Korea, Japan, Australia, Southem Europe, Central America,
ii
some islands of the East and West Indies (1), and in considerable quan
tities in the United States.
Sorghum vulgare was probably introduced to the Westem Hemisphere
through the slave trade from Africa. Beginning in the middle of the
Nineteenth Century, the United States Department of Agriculture began I.
introducing varieties from other parts of the worlds White Durra and
Brown-Durra from Egypt in 1871;, White Kafir and Red Kafir from South
Africa about 1876, Milo from Columbia about 1879, Shallu from India
about 1890, Pink Kafir from South Africa in I90I1, Feterita and Hegari
from Anglo-Egyptian Sudan in I906 and I908 (9). New varieties constantly
are being developed both in this country and abroad.
Standard varieties of sorghum, standing "head high," required
hand harvesting„ In the late 1930* s W. P. Martin, a farmer, propagated
dwarfed stalks of maize growing as mutants in his fields near Lubbock,
Texas. The variety, introduced as Martin Maize in 19l;l, was one of the
first of the commercially acceptable varieties of combine sorghum pro
duced in West Texas, Basic research to develop hybrid varieties of sor
ghum was conducted as early as I918 by R. E. Karper of the Texas Agri
cultural Experiment Station Number 8 at Lubbock, Texas. John B. Seilin-
ger of the Oklahoma A & M Experiment Station at Stillwater, Oklahoma,
and Karper, working independently of each other, introduced the Plains-
mand and Caprock combine varieties of grain sorghum in 19iil. Through
these efforts and others improved varieties have been developed which
require little or no hand labor in production, need less water for larger
^Information gathered through interview with Dr. A. W. Young, Dept. of Agronomy, School of Agriculture, Texas Technological College, June, 1962,
yields, and produce higher quality grain. The hybrids, appearing in com
mercial production in 19^6, brought about as much as a twenty-five per
cent increase in production per acre over previous varieties (2),
extended production into drier areas and into climates with shorter
growing seasons (k)» Continued in5)rovement through research is being
made, especially that conducted at the Texas Agricultural Experiment Sta
tion Number 8 where some 900 strains are currently being tested (12).
New varieties eventually may include development of yellow endosperm
grains which will have carotene id and xanthophyll pigments, as well as
improvements in seed size, threshability, grain composition, and quality
(2).
Production and Economy
Production of grain sorghum in the United States centers mainly
in the Great Plains area, even though acreage planted to grain sorghum
is increasing in the Corn Belt. In less than a twenty year period total
production of grain sorghum has increased from 181;,978,000 bushels in
19l;l; (13) to 1;82,000,000 bushels in I96I (ll;). The I96I average yield
per acre was kh bushels (li;) in comparison to 18.9 average yield per
acre in the years 19l;6-55 (12); with optimum irrigation and fertiliza
tion yields of 129 bushels per acre have been reported (l5). These in
creases are attributed to the use of sorghum hybrids and improved farm
ing techniques (12). Texas is the leading state in sorghum production
with an average of about fifty-one per cent of the total U. S. crop in
the twelve year period from 19l;6-57 (k), forty-eight per cent of the
total national production in 19^9 (12).
Even though wheat and com surpass grain sorghum in total produc
tion in the United States and yield per acre (Table 1), the price advan
tage is in favor of grain sorghum (Table 2) based on recent U. S. govern
ment price supports. Additional economic advantages in favor of grain
sorghum over other grains are:
1. relatively lower production cost due to comparatively fewer cultural operations required, most of which are accomplished mechanically,
2. high resistance to storm conditions and dependability of harvest because grain sorghum is less fragile during the growing period and at harvest than com or wheat,
3. environmental factors which enable grain sorghum to be grown in areas unsuitable to other grains due to sub-optimal or marginal fertility of the land and/or availability of water.2
TABLE 1
U. S. GRAIN PRODUCTION, 196! *
Grain
Com Grain Sorghum Wheat
Total Production (million bushels)
3,51;9 i;82
1,200,000
Yield Per Acre U.S. Average (bushels)
60.1; 1;1;.0 23.5
•''Crop Production, USDA Statistical Reporting Service, I96I (li;).
TABLE 2
AVERAGE SUPPORT PRICES, 1960"
Grain
Sorghum Com Wheat
Support Price per Ton
$30.UO 37.85 60.00
^ Maclay (I6).
^Personal interview with Mr. John H. Baumgardner, Dept. of Animal Husbandry, School of Af^riculture, Texas Technological College.
8
Nutritional Contribution
Of the four leading cereal grains, wheat, rice, grain sorghum,
and corn, grain sorghum is most like com in both physical and chemical
properties. For this reason comparisons of these two grains are made in
this study. Kramer (1;) notes, "The chemical composition of grain sor
ghum is similar to that of corn. Sorghum has more protein, less fat,
about the same amount and proportion of carbohydrate conponents, . . .
and except for the new yellow endosperm varieties, no xanthophyll or
carotenoid pigments" (Table 3).
TABLE 3
COMPOSITION OF THREE LEADING CEREAL GRAINS^
Food and Descr ip t ion
Grain Sorghum Com (yellow) Wheat
68
w 73 o o ^
C a l .
332 355 332
^ •H 0)
-P o u Ol
Gm.
11.0 9.2
12.U
-p cS fe
ate
ota
l oh
ydr
EH ^
u Cfl O
Gm. Gm.
3.3 3.9 1.8
73.0 73.7 72 .1
1
n
o ^ p iQ
o Xi Pi
Mg.
287 256 356
c; o u H
Mg.
k.h 2.1; 3.1;
min
A
lue
4 ctf -P > •rl >
I .U.
(0) 1/510
(0)
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.38
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.15
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Mg.
3.9 2.0 1;.3
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Mg.
(0)
P •H O
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Mg.
28 (0) i io (0) ,1;6
\^ Leung, Woot-Tsuen, et al. (17).
Comparison of the amino acid content of grain sorghum and com
reveals that grain sorghum is higher in per cent protein, as well as in
tryptophan, isoleucine, leucine, lycine, methionine, cystine, phenyla-
line, and valine (Figure 1). Pond, et al. (19), found lysine and threo
nine to be the most limiting amino acids in grain sorghum for growth of
rats. Addition of 0.5 per cent L-lysine and 0.2 per cent DL-threonine
1.9-
1.8 1.7
1.6
.31.5
Pi
0)1.3^
-S 1 2
•' 1 1 ^ 1 . 0
.9 CI
o o rH
? 0) P i
CO
f-i
.8
.7
.6
.5
.1 ;
.3
.2
,1
0 Tk ^
^
/
/
/ 1
1
/
+3
Grain Sorghum / I
Com ^ ^
/
/
/
/
/ /
/
/
/
y /
/
/ A /
A
7! /
/ i
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/
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ine
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(U
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h ^
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Amino Ac ids
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Fig. 1.—Comparison of amino acid content of grain sorghum with com, Orr and Watt (18).
10
to the basal grain sorghum diet produced growth equal to that obtained
with a purified diet containing eleven per cent casein but inferior to
a diet containing twenty-one per cent casein. Isoleucine was found to
be the limiting factor for the growth of rats fed corn diets supplemented
with lysine, tryptophan, valine, and threonine. Benton (20) considered
the growth rate of experimental rats to be good, i.e., 22.3 t 2.3 grams
per week, when 0.6 per cent DL-isoleucine was added to an eighty-nine
per cent corn diet supplemented with 0.1; per cent L-lysine, 0.1 per cent
DL-tryptophan, 0.2 per cent DL-threonine, and 0.2 per cent DL-valine.
Dr. Harvey (21), in a panel discussion at Texas Technological College,
1959, stated that the higher protein content of grain sorghum may be a
decided advantage over com but because it lacks certain essential amino
acids in proportions necessary to be utilized by the body supplementa
tion is required.
Fatty acid components and physical properties are the same as
com oil (2) and may be used in similar ways to take advantage of essen
tial fatty acids.
Analysis of the B-vitamin content of grain sorghum and com show
that thiamine and pyridoxine values are nearly equal, with grain sorghum
having a slight advantage. Grain sorghum, however, is considerably more
valuable as a source of riboflavin, niacin, and pantothenic acid (Table
li).
Common varieties of grain sorghum contain little or no xantho
phyll or carotenoid pigments (2, U, 17); however, through hybridization
yellow endosperm varieties have been developed which contain up to 9
p.p.m. of the carotenoids compared with yellow corn which contains an
average of 22 p.p.m. (22).
11
TABLE k
COMPARISON OF B-VITAMINS OF GRAIN SORGHUM WITH CORN (p.p.m.)*
Vitamin
Thiamine Riboflavin Pyridoxine Niacin Pantothenic acid
Grain Sorghum Mean h.6 1.5 $.9 i;8.0 12.0
Corn Mean k.h 0.6 5.7 23.0 7.0
*Maclay (16).
In view of the multitudinous varieties of sorghum in the world,
few of which have been analysed, Webster (23) states there may be those
which vary sufficiently genetically so that protein quality may be im
proved. Research by Tanner, et al. (21;, 25), and Swanson, as quoted by
Webster, indicate the possibility of modifying the vitamin content, es
pecially niacin, through hybridization. Webster (23) further states,
"It would be very surprising if the content of other vitamins, protein
fractions, and minerals could not be modified by breeding."
r/ v/
Commercial Utilization
Of the 639 million bushels of grain sorghum produced in 1958
about 10 million bushels (about 1.6 per cent) were utilized as food and
other industrial products. "These uses include flour, grits, refined
starch, oil, and gluten feed; starch is further converted into glucose
syrups, dextrose sugar, and dextrins (I6)."
The primary concern in the present milling process of grain sor
ghum is starch recovery. Other materials are by-products, the utiliza
tion of which is an economic necessity. The first real effort to produce
12
commercial starch from grain sorghum was caused by events during World
War H when supplies of raw materials were either cut off or directed
to other uses. The first plant designed to process solely grain sor
ghum was designed by the Com Products Refining Conpany at Corpus
Christi, Texas (26). The Corpus Christi plant employs the wet milling
process to recover purified starch, crystalline dextrose, oil, and pro
tein feeds. The pilot plant for dry milling of grain sorghum is Grain
Products, Inc., located at Dodge City, Kansas. Dry milling produces
endosperm products similar to commeal, grits, flour, and feed (2).
While sorghtim starch granules are almost indistinguishable micro
scopically from com starch granules (27), recovery and purification of
sorghum starch is more difficult (2). The prime difficulties in separa
tion encountered with grain sorghum starch production are: the small,
round shape of the kernel, the large proportion of homy endosperm with
a dense peripheral layer, and red and brown pigments in the pericap (28).
Regular and waxy sorghums differ widely in pasting characteris
tics; each has its counterpart in com (2). Regular sorghum starch pro
duces a paste relatively stable to hot agitation which sets, when cooled,
to a rigid, nonreversible gel; waxy sorghum starch (white milo) develops
high viscosity which can be broken by agitation while hot to a lower
viscosity and does not recover when cooled. Granules of regular sorghum
starch contain twenty-seven per cent amylase, as does cornstarch; waxy
sorghum starch contains only amylopectin. Cross-bonding is possible by
chemical treatment.
A factor in the use of sorghum starch is the higher teiT5)erature
required for gelatinization as compared with com starch (29). The
13
gelatinization tenperature range of milo starches is 67° to 77°C while
com starch granules gelatinize from 62° to 72°C, about a 5°C higher
range for sorghum. Watson (30) considers this a disadvantage in sor
ghum starch utilization; however. King (31) believes this disadvantage
could be modified through research and breeding.
Palatability and Acceptability as Hiaman Food
Watson (2) reports sorghum starches are particularly favored for
use in bland foods because these have less "cereal flavor." Regular
milo starch is excellent in puddings and custard pies (32). Waxy milo
starch is used where more stabilily is required, such as fruit pie
filling, thickened canned foods, soups. Waxy sorghum starch in frozen
food products is quickly and completely dispersible upon thawing and
relatively free from syneresis which implies possible wide utilization
in the frozen foods industiy. Pre gelatinized sorghum starches are use
ful where the addition of liquid results in instant thickening, such as
instant puddings (33). Sorghum dextrins match and surpass tapioca dex
trins in preparation of pastes for clearness and stability in the gel.
Crystalline dextrins are of value in the fruit canning and confectionary
industries (5).
No other reference on the use of grain sorghum in bread products
was found other than a research bulletin published at Texas Technologi
cal College in 19l;2 in which the research team of Bavousett and Kleppe
(31;) developed recipes substituting flour from certain varieties of
grain sorghum (hegari, kafir and milo) for two-thirds of the wheat flour
in muffins, quick loaf breads, and griddle cakes; a ratio of 1:1 was
recommended in biscuits and yeast breads.
CHAPTER n i
EXPERIMENTAL DESIGN
Overall Plan
Tests were conducted using sixteen varieties of grain sorghum
(Table 5) to determine the factors which are proposed in the introduc
tion. These samples ranged in mesh size from a flour, to a coarse
meal (Table 6). The meals were whole grain products; the iyours and
grits were made from endosperm with the germ and seed coat removed,
TABLE 5
GRAIN SORGHUM TEST SAMPLES
Sanple Number
1 2 3
1; 5 6
7 8 9
10 11 12 13 11; 15 16 17
18 19 20
Variety
Whole Milo flavor Milo grit #1 Milo grit #2
D,D. Ey. Popgrain 6662 D,D. Ey, Shallu 657-25-1; Golden Shallu 7530-1-2-2-7-1-3
Red-601 White Endosperm D-55 Yellow Endosperm X-l;9
Golden Kafir 9130-3 Golden Giant 8591-7-1-2 Golden Kafir 872l;-55-3-M Golden Kafir 85ll;-2-l-2-M Golden Kafir 9197-1-1 Golden Hegari 9225-6 Golden Feterita 8737-11-3 Golden Shallu 7530
Industrial Sorghum Flour #6o Refined Sorghum Flour #100 Combination sample l6 & 19,
ratio 3:1
Source
Harvest Queen Mills
Texas Agricultural Experiment Station
Number 8
Texas Technological College, School of
Agriculture
Texas Agricultural Experiment Station
Number 8
Grain Products, Ine,
Grind
Flour Grit Grit
Medium meal Fine meal Coarse meal
Medium meal Medium meal Medium meal
Medium meal Medium meal Medium meal Medium meal Medium meal Medium meal Medium meal Medium meal
Flour Flour
Flour-meal
11;
15
Basic quick and yeast bread formulas were used to determine the extent
to which milled grain sorghum could be substituted for wheat flour and
the modifications which were necessaiy to provide acceptable results,
TABLE 6
SPECIFICATIONS FOR THE MILLING OF CORN PRODUCTS^
Product (classified by size)
Grits
Meals Coarse Medium Cones
Flours Sharp Soft
Sieve Size
6-16 USDS Sieve
16-21; USBS Sieve 2U-1;0 USBS Sieve i;0-70 USBS Sieve
70-100 USBS Sieve 70 max. USBS Sieve
^Matz (U),
^United States Bureau of Standards,
Test samples numbered l6, 19, and 20 (Table 5) were analyzed for
provitamin A (carotine), thiamine and niacin content to determine to
what extent the nutritive value of the whole grain sorghum meal differed
from that of the refined flour (see Table 9, p.29). These test samples
were also analyzed to determine the mesh size, the range of particle
sizes and the distribution of particle sizes within this range (see
Figure U, p. 31).
Evaluation Procedure
A taste-panel of three to five members judged results of each
test using an evaluation device based on organoleptic factors to deter
mine differences in palatability (35). All taste-panel members were
16
experienced in testing and judging flour mixtures, A scale of one to
five points (very poor to excellent) was used to score each product on
the palatability facotrs: appearance, odor, texture, flavor, and over
all acceptability, making a possible score of twenty-five points (Fig
ure 2), The object was to score the products according to acceptability
as an entirely new food without comparing results to a preconceived
"standard,"
SCORE CARD
Scale: 1 2 3 1; 5 Very Poor Fair Good Excellent Poor
Please score each product in each classification by number according to the scale.
PRODUCT
I
n
III
IV
APPEARANCE ODOR TEXTURE FUVOR OVERALL ACCEPTABILITY
POSSIBLE POINTS
25
25
25
25
YOUR SCORING OF PRODUCT
Fig. 2.—Evaluation device for scoring breads
Development of Formulas
In each of the three series of tests a basic formula (Table 7)
was first produced using wheat flour for the purpose of standardization
of techniques. Each successive test used the formula judged best in the
preceeding test as the basic formula. One ingredient, technique, or
17
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variety of grain sorghum was varied to determine the best results, as
suggested by Lowe (35). Tests were continued until an acceptable baked
product was produced and conclusions were reached concerning accepta
bility of the varieties and the mesh size of the flour or meal being ex-
amined. Formulas developed by this procedure are tabulated in Table 8.
Test Series
Three separate series of tests were conducted (Figure 3). Each
test-series involved examination of certain varieties of grain sorghum
and of different mesh sizes. Basic quick and yeast bread formulas were
used to detennine palatability and the extent to which milled grain sor
ghum could be substituted for wheat flour.
Test Series I
In Series I six sanples (Figure 3, lA) ranging in mesh size from
flour to coarse meal (IB) were tested using muffins and griddlecakes to
determine the possible acceptance in typical American quick breads (IC).
The flours in Series I were milled from commercial hybrid milo and the
meals were from experimental hybrid yellow endosperm varieties. The
study began with basic muffin and griddlecake formulas (Table 7) which
were modified in amounts and types of ingredients to produce acceptable
results. During Series I hydration of the meal was a technique used as
a means of improving palatability and acceptability. Hydration of muf
fin batter was accoirplished by (1) combining liquid and flour and al
lowing the mixture to stand at room tenperature for various lengths of
time, 2, U, 8, and 12 hoursj (2) combining liquid and flour and refrig
erating the mixture for like periods of time; (3) combining all
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22
ingredients, mixing sufficient3y to moisten dry ingredients and refrig
erating the mixture for the same periods of time, Griddlecake batter
was hydrated by combining all ingredients and allowing the mixture to
remain (1) at room temperature or (2) refrigeration te]75)erature for
two hours.
Test Series II
Test Series II was conducted using three commercial hybrid varie
ties of grain sorghum (Figure 3, HA) furnished by the Texas Technologi
cal College School of Agriculture, These varieties were being studied
in the School of Agriculture in relation to palatability for and accept
ability by hogs. The staff of the DepartmEnt of Animal Husbandly also
was interested in the acceptability of the varieties and their palata
bility as food for humans. The three varieties were a red grain, a
white endosperm grain, and a yellow endosperm grain. The yellow endo
sperm variety differed from the experimental hybrid yellow endosperm
varieties in this study in that it was not a true hybrid, but one of
cross parentage. The grind of the three samples was fine to coarse
meal. The muffin formula developed in Series I was used with no fur
ther modifications to determine acceptability and palatability of these
grain sorghum varieties and influence of mesh size. The griddlecake
fomiula was converted to include dried buttermilk instead of non-fat
dried milk solids and modifications were also included as to type and
amount of leavening, amount of liquid, and time of hydration, A basic
tortilla formula was used to examine the possibility of enploying the
"corn-like" properties of grain sorghum in this Mexican-American food
23
(Table 7). A tortilla is a small round unleavened bread made of very
finely ground com (7) or occasionally of wheat flour in the United
States, A similar bread in India is known as "chapatis" (36) and in
South Africa as "mealies" (37). The wheat flour tortilla formula was
modified by the substitution of grain sorghum meal for wheat in amounts
of twenty-five per cent and fifty per cent, by volume; non-fat dried
milk solids were used to in5)rove the nutritive value and palatability
of the tortilla. The tortilla was cooked by two methods, baked on a
dry griddle, and deep fat fried at i;25°F.
Test Series III
The third phase was conducted using nine varieties of grain sor
ghum. Eight san^jles were of experimental hybrid yellow endosperm grains
from the Texas Agricultural Experiment Station Number Q; two sanples
were commercial hybrid milo products from Grain Products, Inc., Dodge
City, Kansas (Figure 3, IIIA). The yellow endosperm varieties were
medium meals (HIB) while the milo products were flours of number 6o
and 100 mesh size. As the test series progressed a combination of
meal and 100 mesh flour was used in a ratio of 3:1. Basic formulas
for muffins, griddlecakes, and tortillas were used with no modification
in order to test varietal difference and mesh size. Modifications in
a basic cookie formula (Table 7) were: type of sweetening; amounts of
liquid, sugar, non-fat dried milk, and egg; use of peanut butter and
maple as flavoring agents; and length of cooking time. A basic yeast
bread formula required no modification when grain sorghum flour-meal
was substituted for part of the wheat flour in a ratio of 1:2. When
21;
substituting grain sorghum for part of the wheat in a ratio of 1:1,
modifications in technique, amounts of flour and non-fat dried milk,
and type of fat were made.
CHAPTER IV
RESULTS AND DISCUSSION
Varietal Difference
In recognition of the multitudinous varieties of grain sorghum
in the world, the sixteen varieties tested as part of this study seem
small. The significance of varietal difference in palatability is
evidenced by the marked differences discovered in this assortment of
varieties. The acceptance of the varieties ranged from "acceptable,
unique, interesting texture" to "objectionable, highly unacceptable"
and "awful color" when judged by the taste-panel. Products rated from
a score of seven to twenty-five in acceptability due to varietal dif
ference. The experimental hybrid yellow endosperm varieties scored
higher than did the commercial hybrid varieties.
Pigment Differences
Certain pigmented commercial hybrid varieties (Figure 3) such as
the milo flour and grits in Series I, the red grain in Series H and
the sorghum flours in Series III produced baked products of a dark
grey-blue color. This coloration is due to red and brown pigments
and tannin in the exterior seed coat and hull (28, 2), While the re
moval of the outer pigmented portion of the grain is possible by use
of an abrasive process, this area of the grain contains much of the
protein and other nutrients which make grain sorghum preferable to com.
Thus in removing the objectionable outer colored layers the nutritive
content would be diminished as well.
25
26
In this study whole grain products were preferred over those
that were refined because of the greater nutritive contribution. For
this reason the varieties which provided acceptable food products
without the removal of the outer seed coat, such as experimental hybrid
yellow endosperm varieties in Series I and n i , were preferred.
Two commercial hybrid varieties of sorghum which were expected
to be acceptable, white endosperm and yellow endosperm (Series H ) ,
contained enough tannin to produce unsightly off-colored food.
The experimental l^brid yellow endosperm varieties produced by
the Texas Agricultural Experiment Station Number 8 and used in Test
Series I and III were the most acceptable in appearance. The pigmen
tation of these varieties is not as intense as that of yellow com,
but while they produced neither a true yellow nor a white cnmib in
baked foods, the taste-panel felt the yellow experimental hybrid endo
sperm varieties would receive the best acceptance by the general pub
lic. Only a slight difference in preference was expressed by taste-
panel members between varieties in this class. However, in Series III,
samples number 12, Golden Kafir, and number 36, Golden Feterita, were
judged the most acceptable.
Texture
One sensory factor which seemed to be associated with variety
was a certain gritty texture or powdery, sandy feel in the mouth when
tasting the product. This was more pronounced in commercial hybrid
varieties than in the experimental hybrid yellow endosperm grains; how
ever, in Series H I , san jle number H, African Golden Giant, the gritty
texture was more noticeable than in others of this class.
27
Watson, et al, (38), state that the grain sorghum kernel contains
a large proportion of homy endosperm and a layer of dense cells rich in
protein at the periphery of the endosperm just inside the aleurone layer.
Watson also observed an "apparent resistance of the contents of the peri-
pheral cells to fragmentation along with the mpture of endosperm cell
walls during milling," resulting "in release of the intact contents of
the individual cells into the starch process streams," The gritty tex
ture in whole grain sorghum test sanples may be due to this resistance
to fragmentation of the peripheral layer but this does not explain the
powdery feel in the mouth of foods baked from the more highly refined
flours in which the outer layers of the grain were removed.
Taste
The experimental hybrid yellow endosperm varieties were superior
in taste and odor to the commercial hybrid varieties. Some of the lat
ter were reminiscent of a feed store in odor. While some members of the
taste-panel could detect in some products a certain "grain" odor when
hot muffins were first broken open, other members could not. A charac
teristic taste and odor, somewhat suggestive of com, was found accept
able by the taste-panel.
Overall Acceptability
The taste-panel members were unanimous in the opinion that the
experimental hybrid yellow endosperm varieties were preferable to the
commercial hybrid varieties of grain sorghum for use in conventional
quick and yeast breads. An interesting point, however, is that in
28
Series H , in the test of three commercial hybrid varieties the prefer
ence was for the highly pigmented red variety. While the color was
conceded to be "unusual," the red variety rated higher in the other sen
sory factors: odor, texture, flavor, and overall acceptability. The
scores ranged from thirteen to twenty with an average of sixteen for
the white and yellow endosperm varieties compared with scores from four
teen to twenty-two with an average of nineteen for the red variety. Fif
teen points indicate a "fair" product on this scale and twenty points a
"good" product. The difference was not sufficient to indicate a strong
preference. By comparison the scores in similar tests for varietal
differences in the experimental hybrid yellow endosperm varieties. Series
III, were consistently higher, with scores ranging from sixteen to
twenty-four with an average of twenty-one. Taste-panel members commented
that there was very little difference in palatability and acceptability
of the varieties in Series III, but of the eight varieties, numbers 12
and 16 seemed somewhat more acceptable than the others.
Nutritive Contribution
Certain of the more palatable varieties of grain sorghum in this
study were analyzed to determine their content of provitamin A (caro
tene), thiamine, and niacin (Table 9). Samples analyzed were Numbers
16, 19, and 20. Neither the experimental hybrid yellow endosperm vari
ety nor the commercial hybrid variety contained carotene even though
this is one of the iirprovements being sought in the former through ex
perimental hybridization. The analysis shows that the refined grain
sorghum flour contains only 38.6 per cent of the niacin and 29.7 per
29
cent of the thiamine of that found in whole grain sorghum meal. The
combination flour-meal, which was preferred for its cooking qualities,
contains 91;.3 per cent of the niacin and 81.1; per cent of the thiamine
of that in whole grain sorghum meal. This emphasizes the importance of
utilizing the whole grain, or as nearly whole grain as possible, to pro
duce foods of high nutritive contribution as well as those of acceptable
palatability.
TABLE 9
VITAMIN ANALTSIS OF THREE GRAIN SORGHUM SAMPLES .•«•
Sample Number
16 19 20
Variety
Golden Feterita Refined Sorghum flour Combination flour-meal, samples l6 and 19 in 3:1 ratio
Analysis TTarcTtehe
Mg/lb 0 0
0
Niacin
Mg/lb 17.60 6.80
16.60
Thiamine
Mg/lb 2.1;7 .731;
2.01
•' Analysis by Texas Agricultural Experiment Station, College Station, Texas.
Influence of Mesh Size
The characteristic most enjoyed by taste-panel members was the
coarse, mealy texture of breads made from grain sorghum milled to a
fineness of medium meal (Table 6). In the original series (Series I)
the meals ranged from fine to coarse. The preference of the taste-
panel for the.Popgrain in this test series may have been due to some
extent to the general preference for a medium grind meal throughout
this study. The coarse meal contained larger particles of husk and to
some individuals it was actually "scratchy" in the mouth and throat.
30
Baked foods made from the grain sorghum flours, while appealing to those
who personally liked a smoother feel to their foods, were generally
thought to have lost some of the "characteristic appeal" of the products
made from the coarser ground meals.
A combination of grain sorghum meal and flour, in a ratio of 3:1,
was found to be the most successful in food products. Samples of the
meal, the flour, and the combination flour-meal were analyzed to deter
mine the range of particle sizes and distribution of particle sizes
within this range (Figure 1;). This analysis shows a range and distri
bution of particle sizes in the combination flour-meal which is a modi
fication of both the meal and the flour and which has definite advan
tages in cooking.
Effects of Ifcrdration
During the first series of tests (Series IB) hydration of the
meal or the batter was found to improve the quality of the quick breads.
Lowe (35) suggests the "palatability of bran muffins can be iiiproved by
soaking the bran in wann milk" or allowing the batter to stand before
baking to hydrate the bran and make it softer. This may have been a
factor in the improved quality of hydrated products in certain varie
ties of grain sorghum. While hydration of the grain sorghum meal or
the combined ingredients in the fom of a batter for a period of two to
four hours produced favorable results, longer periods of hydration were
not advantageous. Hydration periods of 8, 12 or 21; hours resulted in
products which were progressively "soggy" and which had odors of fer
mentation, even when stored under refrigeration.
31
Cumulative Per Cent Weight Retained
U,S. Mesh 20 Uo 60 80 100 120 Uo 170 200 325
Per Cent Cumulative Weights
Sample No. 15" 3.0 35.6 63.0 72,7 77.7 81,1 81;.l; 87.0 88,8 92,6
Sample No. 20|Sample No. 19 2,6 28,8 50.8 59.2 63.1; 67.1; 72,7 78,3
M
None None None None 0.5 17.8 36,8 51.7 60,7 77.i
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Hydration of combined ingredients in the form of batter resulted
in some loss of leavening, especially since the meal settled to the
bottom of the container and required stirring before cooking. However,
grain sorghum products were found to be very easily leavened so that
some loss seemed not to affect adversely the quality of the baked pro
duct. The advantage of the more simple procedure, i,e, combining all
ingredients before hydration, seemed to outweigh the slight loss of
leavening which occurred.
In the third test series (Series IIIB) hydration was abandoned
in the interest of simplicity. Taste-panel members found so little im
provement in the products made from hydrated batters over those from
non-hydrated batters as to make the extra effort appear to be futile.
Hydration was effective only with coarse grinds.
Viscosity of Batters
The most outstanding difference caused by variation in mesh size
was the higher viscosity of mixtures made from milled grain sorghum of
smaller particle size. The flours were much superior to the meals in
forming a viscous batter due to the absorption of more liquid by the
greater surface area of the smaller particles. In mixtures the batters
made from flours retained the viscosity and produced baked products with
greater volume. This was true of the hydrated as well as the non-
hydrated batters.
Combination of Meal and Flour
The highest degree of success in use of milled grain sorghum in
conventional flour mixtures was achieved by using a combination of medium
33
meal and number 100 mesh flour. Ratios of 1:1 and 3:1, meal to flour
were used. Since the 3:1 ratio provided satisfactory results and main
tained a higher proportion of the whole grain meal, this ratio was pre
ferred. If such a range in particle sizes is unavailable one tablespoon
(9 grams) of wheat flour may be substituted for a like amount of grain
sorghum meal. The grain sorghum flours in this study were of the com
mercial hybrid varieties which are pigmented and gave the bread a slight
off-color. Even more acceptable results could be obtained if the ex
perimental hybrid yellow endosperm varieties were milled to produce
flour in this range and distribution of particle sizes (Figure 1;).
Extent of Use in American Foods
Milled grain sorghum may be substituted successfully for one-
fourth to one-third of the wheat flour in most conventional American
flour mixtures without alteration of formulas (31;). In determining
the extent to which grain sorghum could be substituted for wheat flour,
100 per cent grain sorghum was used whenever possible with certain
modifications in the basic wheat flour formulas to provide acceptable
results. Foods prepared with milled grain sorghum, using formulas
developed in this study, are illustrated in Figures 5 through 9-
Muffins
The initial substitution of 100 per cent milled grain sorghum
for wheat flour in a basic plain muffin formula (Table 7) required im
provement. Subsequent test batches of 100 per cent grain sorghum muf
fins with modifications of the formula produced a product which ranged
31*
Fig. 5.—Grain sorghum muffins
F±r^, 6.--Grain sorf hum griddlecakes
2>^
* •»
_ /
Fig . ?.—Conventional griddle-baked t o r t i l l a s ( le f t ) and deep-fat fried chips (r ight) made with grain sorghum
k"i'i;.;f«<Si!S m. * < « . ' • - • '•>•*'••.
• i * . • . * . • • • •
T^ -•' -" ^ • ^ ^ : - ^ .f^i ^ V
» ' ^
wm
i ' .
'V ' ^ 1
IE. ^ . , - • ^ .
• i f i^^^
•. • ' . ' ? . !
^^'£^^^H[ '^^^J-
. • > _ • . • » . • . ,
Iv - .JM • • ' ^
s Fig. 8.—Maple drop cookies (left) and peanut butter
cookies (right) made with grain sorghum.
36
Fig. 9.—Grain sorghum yeast bread
37
in scores from seventeen to twenty-three with an average of twenty-one
of a possible twenty-five (Figure 2). The 100 per cent grain sorghum
flour-meal combination produced the best results with a score of twenty-
four. Alterations in the basic formula were; increased sugar and egg
and a decreased baking time (Table 8). These modifications were used
throughout the study with satisfactory results.
Muffins with a high ratio of milled grain sorghum were easily
mixed without the probability of developing "tunnels" due to overmixing.
The wheat protein, gluten, hydrates in muffin formulas to the extent
that elastic strands form large air pockets during baking. Grain sor
ghum protein lacks the tenacious qualities of wheat gluten and produces
a batter which is grainy rather than smooth and elastic. This charac
teristic in grain sorghum batters is an advantage in muffin and griddle
cake formulas because overmixing does not- adversly affect the texture
of the product.
Griddlecakes
Modifications of the basic griddlecake formula (Table 7) for use
with 100 per cent grain sorghum were: decreased liquid, leavening and
oil. Margarine substituted for the original amount of oil, by weight,
produced good results and improved the flavor. The modified formula
(Table 8) resulted in a griddlecake which scored an average 23.5 with
a range of twenty-two to twenty-five.
Modification of the amount of liquid was necessary when grain
sorghum meal was used in mixtures containing a high ratio of liquid
to flour, such as griddlecakes. Grain sorghum meal absorbs less liquid
38
than wheat flour because the protein is less hydrophilic than wheat glu
ten and the particle size is larger. The need for reduction in leaven
ing may be due to the fact that protein particles of grain sorghum do
not adhere to each other when moistened forming a very weak cell struc
ture which retains a very limited volume of gas from a leavening agent.
In the grain sorghum formula the amount of leavening commonly used in
wheat flour products resulted in the escape of gas, leaving large holes
in the surface of a heavy, conpact griddlecake. The higher fat content
of grain sorghum, see Table 3, over wheat is responsible for the use of
less fat in grain sorghum griddlecakes.
In altering the modified griddlecake formula for the use of dried
buttermilk in the place of non-fat dried milk these changes were made:
substitution of soda for part of the baking powder for leavening, fur
ther reduction of leavening and liquid.
Tortillas
Grain sorghum may be substituted satisfactorally for wheat in a
ratio of 1:1, by volume, in a basic wheat flour tortilla formula. In
creased non-fat dried milk solids improved the product by reducing to
some extent the characteristic gritty texture of the grain sorghum.
Sectors of round tortillas were fried in deep fat and produced
an interesting variation which could be used for snacks or as a meal
accompaniment. The stratified layers of dough separate in frying re
sulting in a "puffed" chip. A reduction in fat content of the formula
compensated for absorption of fat in the frying process.
39
Cookies
In exploratory work, milled grain sorghum was substituted for all
the wheat flour in random drop cookie formulas producing surprisingly
acceptable cookies. This indicates that grain sorghum is versatile in
its usefulness in flour mixtures. Modifications of a basic drop cookie
formula which resulted in an improved product were: reduced liquid and
sugar, increased egg and non-fat dried milk solids (Table 8), Maple
flavoring was more complimentary to grain sorghum than vanilla, as was
brown sugar instead of white sugar. Peanut butter used as an ingredient
and substituted for part of the fat in a ratio of 2:1 produced an espe
cially tasty cookie.
Chilling the cookie dough reduced the gritty texture and prevented
excessive spreading of the cookie during baking. Grain sorghum cookies
required less time in baking than conventional wheat flour cookies.
Yeast Bread
Milled grain sorghum may be substituted successfully for one-
third by volume, of the wheat flour in a basic formula (Table 7). How
ever, for acceptable results at higher ratios modifications are neces
sary. The best results were obtained with a 1:1 ratio of grain sorghum
meal and high gluten bread flour with increased non-fat dried milk
solids and butter used instead of oil as the fat (Table 8). The pro
duct of the formula just described received scores ranging from eighteen
to twenty-three with an average of 20.5 points on a twenty-five point
scale (Figure 2).
i;0
The formation of a tenacious mixture with the bread flour before
adding the grain sorghum was advantageous in obtaining a loaf of satis
factory volume. The technique used was: (1) combine bread flour and
all other ingredients, except grain sorghum in the usual method; (2)
beat the mixture with an electric mixer at medium speed for about two
minutes, or until the batter is "ropy"; (3) add grain sorghum and fol
low the usual procedure of kneading. Maximum development of wheat
gluten by this method resulted in increased volume of the baked loaf.
Bread doughs in these tests were "sticky" and required additional
flour during the kneading process. This emphasizes the inability of
grain sorghum protein to absorb as much liquid as wheat protein.
Increased non-fat dried milk solids improved the grain sorghum
bread. The results were a less gritty texture of the crumb.
Finding a satisfactory length of rising after formation of the
loaf was a problem during these tests. Test batches of bread rose
quickly and were more compact near the bottom of the loaf upon baking,
than at the top. In one test three loaves were baked after rising per
iods of twenty, thirty, and forty minutes respectively. The twenty min
ute rising period was judged best after using a "Micrometer Adjustment"
Penetrometer to determine the least variance in density between the top
of the loaf, one-quarter of an inch beneath the crust, and the bottom
of the loaf, one-quarter of an inch inside the crust (Table 10).
The cell structure of the grain sorghum loaves consisted of
translucent cell walls with granular particles deposited therein. The
translucent quality is in contrast to the opaque cell structure of
wheat products. This unique characteristic of grain sorghum bread may
la be due to the sorghum starch which forms gels superior in clearness to
other starches (39).
TABLE 10
PENETROMETER TEST OF YEAST BREAD
Sample Number
I II III
Rising Time (minutes)
20 30 Uo
Pentrometer Readings Top of Loaf
mm. 10.0 9.2 7.8
Bottom of Loaf
mm. 9.7 8.0 6.5
Variance
mm. .3
1.2 1.3
Mixes
In an exploratory investigation of the potentialities of mixes
containing grain sorghum flour, a combination of ingredients was used
as listed in Table 11, The mix could be combined with different liquids
in varying amoxmts and with other ingredients in order to produce cer
tain quick breads. This is an introduction to further research on the
marketing of grain sorghum products for human food. A mix such as this
could be utilized by homemakers for a variety of interesting products
including muffins, griddlecakes, drop cookies and loaf breads. In-this
way grain sorghum products could be established in the domestic market
as a "new" food which is unique, appetizing, and appealing in its own
right rather than as a substitute for other cereal grains.
For the foreign market, a packaged mix might utilize grain sor
ghum as the major ingredient in a product already acceptable to certain
peoples either in the countries buying farm produce from the United
States or in those with large underdeveloped areas. Such a mix might
well be a nutritionally balanced multipurpose food product adapted to
1;2
the cooking facilities and eating habits of the people. A mix incor
porates many advantages for this kind of merchandising in that the in
gredients could be packaged in family size containers for safe, conven
ient storage and all essential dietary components could be included in
an acceptable form for the people involved.
TABLE 11
PROPOSED GRAIN SORGHUM MIX AND VARIATIONS
Product
Basic Mix
Product
Muffins
Griddlecakes
Grain Sorghum Meal
3/l;c
Mix
1 l/3c
1 l/3c
Sugar
2T
It
Wheat ] Flour
•h
Oil
2T
IT
^m 1
1
2
Leavening
It
Salt
It
Non-fat Dried Milk
3 to 5 T
Method 1 (Combine ingredients and store in tightly closed container.
Other 1 Method
jHgO
7/8CH2O
Standard muffin method of mixing. Bake at i;25°F about 20 mins. Yield: 6 medium muffins.
Standard muffin method of mixing. Bake on griddle at i;25°F about 2 mins. Yield: 10-12 small cakes.
CHAPTER V
CONCLUSIONS
The basic conclusion reached in this study is that milled
grain sorghum can be useful as food for humans. Among the varie
ties of grain sorghum which are commercially available or in the ex
perimental stage of hybridization, many are palatable and some are
highly acceptable as human foods, A whole grain sorghum meal with a
range in particle sizes about forty per cent of which are of the finer
mesh sizes, number 100 mesh and finer, is the most desirable for use
in bread products. One hundred per cent milled grain sorghum can be
substituted satisfactorally for wheat flour in basic quick bread for
mulas with some modifications in types and amounts of ingredients. A
substitution of grain sorghum for one-half the wheat flour produces
acceptable results in yeast breads and tortillas, with certain modifi
cations of the formula.
Specific conclusions based on results of this study are:
1, experimental hybrid yellow endosperm varieties of grain sor
ghum were preferred to commercial hybrid varieties because
of:
a. a more pleasing appearance of breads without the grey-
blue color of the pigmented varieties,
b. a less gritty texture than that from the commercial hy
brid varieties which have a harder outer seed layer,
c. the simplier, faster methods of mixing which did not re
quire several hours of hydration as did the commercial
hybrid varieties,
1;3
hh
d. a pleasant flavor and acceptable odor, whereas, the com
mercial hybrid varieties had odors suggestive of a feed-
store;
2. a combination of medium meal and flour was preferred to either
flour or meal alone because of:
a. the characteristic crunchy, mealy texture of breads pre
pared with the flour-meal combination,
b. batter hydration being required for acceptable results
only with the coarsest grinds,
c. the acceptable batter viscosity obtained with the combina
tion flour-meal;
3. when using 100 per cent grain sorghum, modifications of the
formula which improved results were:
a. increased protein in the form of non-fat dried milk, egg,
or, in some cases, peanut butter reduced gritty texture
of breads to a pleasant crunchiness,
b. reduced liquid due to the larger particle size of the
meal and to the inability of grain sorghum protein to
absorb liquid as well as wheat gluten does,
c. reduced amount of leavening in quick breads or reduced
length of rising time for yeast breads,
d. reduced cooking time for some products, especially when
the liquid of the formula was reduced.
The experimental hybrid yellow endosperm varieties of grain sor
ghum were preferred to the commercial hybrid varieties in appearance,
flavor, odor, overall acceptability and cooking quality. This implies
a need to encourage the production of the more acceptable varieties of
grain sorghum rather than those which only produce the highest yields
per acre. A reorganized marketing system on the basis of grain quality
in relation to yield would prove more equitable than the current prac
tice. This study emphasizes the wide difference in consumer preference
and actual production of grain sorghum.
Utilization of grain sorghum as food for humans is entirely possi
ble in the United States; grain sorghum already has a place in the diet
of people in some foreign countries. The nutritious and appetizing foods
which can be prepared with grain sorghum, as well as economic advantages
in producing the grain, suggest the emergence of a new food on the domes
tic market and a vast opportunity for improving the inequality of sup
plies and nutritive content of the world food supply.
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