Emmer (Triticum turgidum ssp. dicoccum) Flour and Bread

C H A P T E R

7 Emmer (Triticum turgidum ssp. dicoccum) Flour and Bread Ahmad Arzani Department of Agronomy and Plant Breeding, College of Agriculture, Isfahan University of Technology, Isfahan, Iran

O U T L I N E Introduction

89

Emmer Impact on Combating Malnutrition

93

Type of Utilization

91

Future Direction of Research

94

Bread-Making History

92

Summary Points

96

Flour and Bread Fortification With Emmer

92

References

96

INTRODUCTION Wheat is one of the most abundant sources of protein and energy in the world, and it is consumed as bread—a major staple food—in most countries.1 The importance of wheat originates from the properties of wheat gluten, a cohesive network of strong endosperm proteins that stretch with the expansion of fermenting dough, and yet congeal and hold together when heated to produce a “risen” loaf of bread. The stretchable mass of gluten, with its ability to deform, expand, recover its shape, and trap gases, is critical to the production of bread and all fermented products. Of all the cereals, wheat is unique in this respect. Rye grain has this property to a lesser extent as well. Throughout the centuries, traditional bread varieties have been developed using the accumulated knowledge of craft bakers regarding how to make the best use of available raw materials to achieve the bread quality they desire. In some countries, the nature of bread-making has been preserved in its traditional form, whereas in others, it has changed considerably. The flatbreads of the Middle East and the steamed breads of China are examples of traditional bread varieties that are still a vital part of the culture of the countries in which they were originally produced and are still baked in large quantities. The number of people suffering from micronutrient malnutrition worldwide has grown rapidly during the past several decades. It can be claimed, therefore, that the current estimates of one-third to one-half of the world’s population suffering from micronutrient malnutrition2 reflect its global proliferation, particularly in developing countries. This alarming trend is thought to be caused primarily by the replacement of ancient crop varieties.1 Modern plant breeding has been historically directed toward high agronomic yield rather than nutritional quality. Increased grain yield may have resulted in lower density of minerals in grain, although evidence for the traditional bread varieties that still exist is contradictory.3 Biofortification, aimed at enhancement of micronutrient concentrations and its bioavailability in plant foods through genetic improvement, is a rational approach for diminishing the micronutrient malnutrition problems. The requisite conditions for diversification of crop species and the growing demand for nutritionally healthy food products and the therapeutic properties of foodstuff have resulted in a renewed interest in ancient wheats such

Flour and Breads and their Fortification in Health and Disease Prevention https://doi.org/10.1016/B978-0-12-814639-2.00007-1

89

© 2019 Elsevier Inc. All rights reserved.

90

7. EMMER (TRITICUM TURGIDUM SSP. DICOCCUM) FLOUR AND BREAD

as emmer (Triticum turgidum L. ssp. dicoccum Schrank ex Sch€ ubler) and einkorn (Triticum monococcum L.). Wheat varieties (Triticum spp.), the staple crops of early civilization, are complex, living, and dynamic species, with many mysteries yet to be discovered. The manufacture of flour for a variety of products, such as leavened and unleavened breads, cakes, biscuits, pasta, and noodles, is the most common food use of wheat grains. The physicochemical attributes of the gluten protein constitute of wheat are the primary factors contributing to the unique potential of its flour dough in bread-making.1 This unique potential in dough rheological properties and the bread-baking quality of wheat flour lead to its global distribution and utilization. The required elasticity of the dough is provided by the physicochemical properties of gluten, which makes risen dough rise to produce a loaf of baked bread. The gluten viscoelastic networks retain the carbon dioxide (CO2) gas bubbles trapped inside the fermenting dough, which is critical in the production of various fermented products and breads. Hulled wheats include species that bridge between cultivated (bread and durum) and wild wheats, and they have hulled kernels and nonfragile spikes. In addition, these ancient wheats were the earliest to be domesticated (almost 10,000 years ago) and contributed significantly to the phylogenesis of modern wheats.4 The hulled or ancient wheats, like modern wheats, exist at all three polyploidy levels: diploid (2x), tetraploid (4x), and hexaploid (6x). Emmer (T. turgidum ssp. dicoccum, 2n ¼ 4x ¼ 28), einkorn (T. monococcum L., 2n ¼ 2x ¼ 14), and spelt (Triticum spelta L., 2n ¼ 6x ¼ 42) comprise the three wheat species belonging to the group of cultivated ancient wheats. At the tetraploid level, T. turgidum L. ssp. dicoccum (Schrank ex Sch€ ubler) Thell (emmer wheat) is the domesticated form of T. turgidum L. ssp. dicoccoides (K€ orn. ex Asch. and Graebner) Thell (wild emmer), and, in turn, durum wheat (T. turgidum ssp. durum (Desf) Husn.) originated from the cultivated emmer (Fig. 1). The free-threshing hexaploid bread wheat (Triticum aestivum L., AABBDD) in common use today was most likely derived from a hulled hexaploid progenitor that originated from hybridization between the tetraploid emmer wheat (T. turgidum ssp. dicoccum, AABB) and the diploid goat grass (Aegilops tauschii, DD).5 The loss of strong glumes, which convert hulled wheat into free-threshing wheat, is considered to be an important trait for wheat domestication. The major genetic determinants of the free-threshing habit are recessive mutations at the Tg (tenacious glume) locus, accompanied by modifying effects of the dominant mutation at the q (speltoid) locus and mutations at several other loci.6 This characteristic is considered as the fundamental morphological difference between durum and emmer wheats. Emmer wheat originated in a more eastward location, in the mountains of the Fertile Crescent, an area in the Middle East stretching from Palestine, Jordan, and Lebanon to Syria, Iraq, and Iran, where its wild progenitor (T. turgidum ssp. dicoccoides) still thrives.7 As the main wheat in the Old World during the Neolithic and Bronze ages, it played a strategically important role as part of the human diet in the ancient civilizations, including those of the Assyrians, the Babylonians, and the Egyptians (Fig. 2). Later, it also spread to Ethiopia on the Abyssinian plateau, where it is still being cultivated and appreciated today. Emmer is still grown in some areas of the Balkans, Turkey, Italy, Iran, Caucasia, Ethiopia, and India. However, emmer has never been subjected to breeding programs, and only its landraces and wild forms are currently available.

FIG. 1 Spikes, spikelets, and grains of emmer wheat.

2. FLOURS AND BREADS

TYPE OF UTILIZATION

91

FIG. 2 The Fertile Crescent (the area in light gray on the map) is known as the domestication site of wheat. It includes the Levant and Mesopotamia, as well as Sumer, the birthplace of the first civilization, and Mesopotamia in the Bronze Age, containing the Sumerian, Akkadian, Babylonian and Assyrian empires.

Consumers are becoming increasingly aware of the benefits of including a variety of cereal grains in their diets. Increased consumption of cereals should spawn consumer interest in seeking out breads and products made from cereal grains other than common bread wheat cultivars. The key factor in producing light-texture breads is the gluten quality of the flour. The dough properties and baking performance of wheat are determined by the structure and quantity of gluten proteins, which strongly depend on genotype. Whereas desirable gluten traits have been successfully obtained in common bread wheat, little effort has been applied in this area to other cereal crops. Increasing interest in natural and organic products has led to the rediscovery of emmer on the following grounds: • Its food characteristics, which make it especially suitable for preparing many different dishes using whole, pearled, and broken kernels and using flour and semolina to make bread, biscuits, and pasta • Its highly starch-resistant content and its nutritional and healing effects, especially in the treatment of such diseases as high blood cholesterol, colitis, and allergies • Its ability to grow in soils with conventional, low input and organic crop systems • Its superior tolerance to both abiotic and biotic stresses, such as pest, cold, heat, drought, and salinity • Its use as a potential source of genes for economically important traits in wheat breeding programs Its cultivation is especially significant in marginal areas of high altitude, where its low input requirements and cold resistance make the crop economically viable.

TYPE OF UTILIZATION Like einkorn and spelt, emmer is a hulled wheat. In other words, it has tough glumes (husks) that enclose the grains, as well as a semibrittle rachis. Upon threshing, a hulled wheat spike breaks up into spikelets. Thus, hulled wheats are

2. FLOURS AND BREADS

92

7. EMMER (TRITICUM TURGIDUM SSP. DICOCCUM) FLOUR AND BREAD

mainly characterized by keeping their glumes adhered to the grain after threshing, as well as their semibrittle rachis. Milling or pounding is required to release the grains from glumes. Cultivation of the crop is associated with complications and challenges related to the harvesting techniques used and the need to dehisce the spikelets to obtain the grain for human consumption. Emmer’s main use is for human food, though it is also used for animal feed. While it is principally used in breadmaking, it is also used to create a number of other dishes, particularly in rural areas. It may be ground into flour and baked into unfermented bread (pancake). Some people crush it and cook it with milk or water to make a soft porridge. Ethnographic analyses judged by the taste and texture standards of traditional bread in some emmer-growing areas suggest that emmer makes good bread, and this is supported by evidence of its widespread consumption as bread in ancient civilizations. Emmer bread is widely available in Switzerland and found as pane di farro in bakeries in some parts of Italy. Its use for making pasta is a recent response to the health food market, though some believe that emmer pasta has an unattractive texture.8 Bulgur (made of cracked grains of emmer) is also mixed with boiling water and butter to produce a harder porridge. Emmer has been traditionally consumed as bulgur whole grains in different kinds of soups worldwide. In some rural places in Iran and Italy, emmer is also used like rice. Being rich in fiber, protein, minerals, carotenoids, antioxidant compounds, and vitamins, emmer becomes a complete protein source when combined with legumes, making emmer bread and pasta ideal for vegetarians or for anyone simply looking for a plant-based, high-quality protein source.

BREAD-MAKING HISTORY Bread has a long history and, indeed, will have a long future. It is a nourishing food that can be stored to be eaten at later time, which is a desirable attribute that enabled civilizations throughout history to survive. After ancient citizens initiated farming, they strived to develop tools to process the harvested crops, as well as procedures to cook the grains. The first bread was a type of flatbread dating to Neolithic times (New Stone Age), which began in approximately 8000 to 10,000 BC. At that time, bread was produced from emmer and einkorn wheat grains. It consisted of hand-crushed grain mixed with water, which was then laid on a heated stone and covered with hot ashes. People in Sumeria, in southern Mesopotamia, were the first to bake leavened bread. At approximately 6000 BC, they started to mix sourdough with unleavened dough. Sourdough is generated during the natural yeasting process of flour and water, during which CO2 is formed, which in turn causes the dough to rise. The Sumerians passed on their style of preparing bread to the Egyptians in approximately 3000 BC. The Egyptians refined the system and added yeast to the flour. Moreover, they developed a baking oven in which it was possible to bake several bread loaves simultaneously. The Egyptians experimented with adding yeast, which made the dough rise, and the leavened dough created bread that was lighter, yet bigger. The successful achievement of wheat bread loaf production by the Egyptians, the Greeks, and the Romans was considered by them as a sign of the high degree of their civilizations. Nowadays, many forms of bread are produced throughout the world. Hence, the term bread is used to describe a wide range of products with various shapes, sizes, textures, crusts, colors, elasticity, eating qualities, and flavors.

FLOUR AND BREAD FORTIFICATION WITH EMMER Some ancient wheats have a unique composition in secondary components, such as carotenoids and starch, which may play a role as functional food ingredients. Emmer is particularly appreciated for its content of resistant starch, fiber, carotenoids, and antioxidant compounds.9–12 Recently, Christopher et al.12 compared local emmer wheat with two commercial wheat cultivars for protein content, phenolic acid profile, total soluble phenolic content, type 2 diabetes relevant α-amylase, antioxidant activity, and α-glucosidase enzyme inhibitory activities under in vitro conditions. They observed the superiority of emmer wheat with its hull for its antihyperglycemic properties, total soluble phenolic content, and associated antioxidants. Although emmer flour does produce a satisfactory loaf of bread, the quality is not as good as bread made with common wheat. This may have led to emmer and spelt being attributed a higher protein quality than modern wheats, simply because they are mainly used as whole-meal or low-refined flours. However, it should be noted that lysine content and the chemical score are higher in whole grain than in white flour. White flour almost exclusively comprises the endosperm portion of the grains and excludes the bran (aleurone and pericarp layer), which is rich in globulins and albumins as well as essential amino acids such as lysine. Galterio and

2. FLOURS AND BREADS

EMMER IMPACT ON COMBATING MALNUTRITION

93

coworkers13 reported high lysine content (3.1%) for emmer grains. In contrast, it has been known that common wheat protein is deficient in lysine. The poor gluten quality of emmer is confirmed by its low gluten index value.13,14 In addition, Konvalina and coworkers15 stated that emmer has a high grain protein content, whereas the quality of its gluten is inferior to that of bread wheat, as determined by the gluten index and the Zeleny test. It is assumed that the poor gluten quality of emmer is due to its storage protein composition, which is dominated by high concentrations of the intermediate-molecular-weight glutenin (IMWG) group (50–78 KDa), poor synthesis of low-molecular-weight glutenin (LMWG) subunits (30–45 KDa), and the absence of gliadin fractions γ-42 and γ-45.13,16 The pH values of emmer sourdoughs were slightly greater than common wheat sourdoughs, but the concentration of free amino acids, phytase activity, and titratable acidity were higher than in wheat sourdoughs.17 Sensory analysis indicated that emmer flour can be made into fair products of bread.17 The potential use of emmer flour in bread-making could be more promising if it is blended with bread wheat flour. Consequently, the high lysine and low gluten content of emmer wheat could complement those of wheat flour, which is poor in lysine but rich in gluten content. During the last few decades, increasing attention has been paid to phytonutrients, which have significant effects on the reduction of the incidence of aging-related and chronic human diseases. Among the numerous antioxidant compounds present in foods, lipid-soluble antioxidants play a vital role in disease prevention. Interestingly, the natural antioxidant activity of these compounds might complement their positive functional characteristics in maintaining the freshness and shelf-life of food products. Wheat, as the major staple food for humans, is not only a source of energy and protein, but also of such antioxidant compounds. In bread wheat, however, the concentration of carotenoids and other antioxidants is low; these substances are more abundant in emmer wheat. In wheat, whole-grain flour and its bran fraction are a reliable source of fiber, especially the water-insoluble type. In contrast, white flour is not rich in total fiber but is relatively rich in soluble fiber. Epidemiological studies reveal a strong relationship between low fiber intake and many disease conditions, particularly those of the gastrointestinal tract.17 In developing countries, it is believed that a large amount of plant fibers consumed by people in rural areas protected them against many diseases common to people in urban areas, such as cardiovascular diseases, colon cancer, diverticulae, appendicitis, hemorrhoids, and varicose veins of the legs. Research relates high-fiber diets to decreased blood pressure in normal as well as in hypertensive subjects.18 For elevated blood serum lipids, dietary recommendations include increasing carbohydrate consumption to make up 65% of total daily calories, emphasizing complex carbohydrates from natural sources because they influence the absorption of fat-soluble substances from the digestive tract and the reabsorption of bile acids and neutral steroils. These recommendations are given to diabetics as well because cardiovascular disease is the most likely cause of death in these people.19 Therefore, there is growing evidence that high-fiber diets, especially those containing cereal fibers, have definite health benefits in reducing the risk of chronic diseases such as diabetes, cancer, and coronary heart disease. A diet rich in complex carbohydrates improves glucose metabolism in diabetic subjects by increasing their sensitivity to insulin, resulting in reduced dosage requirements.18 Moreover, a high-fiber diet is positively associated with the control of obesity and physical gastrointestinal tract disorders. Accordingly, consumers will be interested in utilizing functional cereal products, which will enhance their health and help them to avoid being overweight. Thus, high-fiber cereal products will be in demand and undoubtedly consumed in great quantities. However, as with most food items, the major criteria for consumer acceptability of cereal products are good flavor and texture. In other words, consumers expect functional cereal products, such as high-fiber breads, to have at least similar good-quality features as standard wheat bread. Hence, emmer flour can fully or partially replace wheat flour in bread products, in order to exploit the advantages of the higher fiber content of emmer wheat.

EMMER IMPACT ON COMBATING MALNUTRITION Considering the growing requirements for richness, diversity, and good quality of food products, the interest in emmer wheat has been greater than ever.20 Perrino et al.21 found high mean values of protein (17.1%) in the grains of 50 emmer accessions. There is also a belief that the gluten structure of emmer differs from that of modern wheat, so people with gluten allergies can safely use it without any adverse effects. Improvement in dietary quality may be the ultimate solution to micronutrient malnutrition in billions of people living in developing countries, which is basically the consequence of their extensive consumption of staple cereals with low quantities of available micronutrients.22,23 Therefore, micronutrient malnutrition is considered a great concern worldwide. Currently, enrichment of staple food crops with mineral nutrients is a high-priority research area as a temporary solution to this problem; however, the major strategy to improve the level of mineral nutrients is to exploit the natural genetic variation in grain concentrations of micronutrients in food crops. With the exception of Ca2+, modern

2. FLOURS AND BREADS

94

7. EMMER (TRITICUM TURGIDUM SSP. DICOCCUM) FLOUR AND BREAD

wheat cultivars with a greater yield potential possess lower grain concentrations of mineral nutrients than the previous cultivars with a lower yield.24 Hence, modern wheat germplasm cannot contribute genetic potential to the development of new genotypes with higher levels of mineral nutrients. On the other hand, current research indicates that primitive wheats, such as T. monococum (einkorn wheat) and T. turgidum ssp. dicoccum (emmer wheat), contain a promising germplasm for improving grain micronutrient concentrations.25,26 To combat global micronutrient malnutrition, therefore, it is essential to approach fortifying and enriching staple food crops with mineral elements as an immediate but only temporary solution. International breeding efforts exploit biodiversity to improve the mineral nutrient levels in food crops. It is well established that modern, high-yielding wheat cultivars have lower concentrations of mineral nutrients than low-yielding older ones do.3,24 Alone, the germplasm of modern wheat cannot provide the genetic diversity required to develop new wheat cultivars with sufficiently high-grain mineral nutrient concentrations. On the other hand, ancient wheats, such as einkorn, emmer, and spelt, contain the germplasm resources that can be exploited to improve the micronutrient value of wheat grains.25,27

FUTURE DIRECTION OF RESEARCH The danger of genetic erosion of crop plants and the potential consequences for agriculture will be evident when their wild and primitive progenitors are considered throughout plant domestication and subsequent breeding. The challenge is to exploit the mostly unrealized potential of ancestral species as a component of sustainable crop production, particularly under less favorable environmental conditions. Therefore, the major task of modern breeders is not only to identify the valuable and outstanding traits of the primitive ancestors of crop plants and introduce them into cultivated crops, but also to undertake genetic improvement projects that address the crops themselves, particularly the domesticated ones. Lage et al.28 demonstrated that genetic variation for quality in tetraploid emmer wheat could be transferred to synthetic hexaploid wheats and combined with plump grains and high grain weight for the purpose of bread wheat improvement. Like other ancient kinds of wheat, emmer is high in protein, fiber, minerals, and phytochemicals. It is also considered to be very valuable in breeding programs for improving wheat cultivars for higher concentration and better composition of health-beneficial phytochemicals. In particular, studies on the genetic diversity of the nutritional and health-beneficial properties of emmer should be carried out in order to explore its potential in breeding programs and for improving the quality of both emmer and bread wheats. By collaborating with the private sector (i.e., millers), modern emmer products that suit the tastes of urban consumers can be developed either by blending the flours of emmer and common wheats or by utilizing the flour of emmer by itself. Diversification in emmer products in the flour industry can be promoted through models coming from countries like Italy that successfully produce emmer products. Emmer (ancient hulled wheat) was one of the first cereals ever domesticated in the Fertile Crescent. Emmer grain has the characteristics of two wild wheats (including wild einkorn) and is known to have been the primary wheat grown in Asia, Africa, and Europe through the first 5000 years of recorded agriculture. But over the centuries, emmer was gradually abandoned in favor of varieties of durum and bread wheats without hulls. By the beginning of the 20th century, higher-yielding wheat cultivars had replaced emmer almost everywhere except in small parts of the world (for the list of regions see Introduction). Wheat is the most widely grown crop and has traditionally been selected for its technological functionality, resulting in the selection of hard bread wheat (Triticum aestivum L.) cultivars with a high level of strong gluten proteins, or durum wheat (Triticum tugidum ssp. durum) making yellow-colored pasta products. However, little interest has been shown in the nutritional and healthy properties of grains and its improvement through breeding programs.29 Table 1 provides a rough comparison of the whole-grain flour compositions of four groups of wheat, including emmer, durum, and bread (hard and soft) wheat based on the means of the tested genotypes within each group. In addition, in spite of the great interspecific variations observed for the nutritional values of the grain in Triticum spp., large variations between emmer wheat and common wheat are also observed for the traits. Table 2 summarizes the available data on the compositions of whole-grain flour in emmer wheat and bread wheat and compares the nutritional status of these cultivated wheats. Current evidence from clinical and epidemiological studies implies that a diet high in whole grains may have a protective role against coronary heart disease,30,31 type 2 diabetes,32,33 age-related eye diseases, and certain types of cancer.34,35 The health-advantageous properties of whole-grain wheat flour have been attributed to the levels of natural antioxidants, including flavonoids, phenolic acids, phytic acids, tocopherols, and carotenoids.36,37 Due to lack of the D genome, the inferior gluten quality of emmer wheat (AABB) compared with bread wheat (AABBDD) is not surprising. Bread-making with emmer wheat flour could be more fruitful if a blend of flours from bread and emmer wheat was used. In this way, the health-promoting compounds, including high lysine content, of 2. FLOURS AND BREADS

95

FUTURE DIRECTION OF RESEARCH

TABLE 1

Whole-Grain Flour Compositions of Emmer, Durum, and Hard and Soft Common Wheats Emmer (T. turgidum ssp. dicoccum)

Durum (T. turgidum ssp. durum)

Hard common wheat (T. aestivum)

Soft common wheat (T. aestivum)

Protein (g)

12.5

12.8

14.8

13.9

Fat (g)

2.4

1.6

1.7

1.6

Total carbohydrate (including fiber) (g)

71

69.5

69.7

70.7

Total fiber (g)

2.7

2.4

2.6

2.5

Ash (g)

1.8

2.1

1.6

1.5

Calcium (g)

38

48

55

54

Phosphorus (g)

360

300

317

275

Iron (mg)

4.7

na

8.2

6.5

Moisture (g)

12.3

14

12.2

12.3

All values expressed as a dry weight percentage. na, not applicable. Source: FAO Corporate Document Repository (http://www.fao.org/documents).

TABLE 2

Mean or Range of Compositions of the Whole-Grain Flours of Emmer and Bread Wheat

Component (dry matter)

Emmer (T. turgidum ssp. dicoccum)

Reference

Bread wheat (T. aestivum)

Reference

Digestible carbohydrate (%, or g per 100 g)

71

38

73a

39

Starch (%)

65

38

68.5

40

Amylose (% starch)

25.1

41

28.4a

42

Dietary fiber (%)

9.8

43

13.4

44

Protein (%)

13.5–19.05

45,46

12.9–19.9

47

Lipid (%)

2.16a

46,48

2.8

49

Ash (%)

2.3

45

1.9

45

Phosphorus (g/kg)

5.12

50

4.18

50

Potassium (g/kg)

4.39

50

5

50

Sulfur (g/kg)

1.88

50

1.4

50

Magnesium (g/kg)

1.67

50

1.44

50

Calcium (g/kg)

0.36

50

0.43

50

Iron (mg/kg)

49

50

38

50,51

Zinc (mg/kg)

54

50

35.0

50

Manganese (mg/kg)

24

50

26

50

Copper (mg/kg)

4.1

50

3.9

50

Sodium (mg/kg)

12

50

10

50

a

Determined by either taking an average value from the genotypes reported in a reference or taking an average from the listed references.

emmer flour could supplement those of bread wheat to attain a better dietary balance.1 However, limited information is currently available on the use of emmer flour as a partial substitute for wheat flour in bread production based on physicochemical and rheological properties of dough and bread, and further research is required to address this. At present, therefore, insufficient data are available on the use of emmer wheat flour as a full or partial substitute for wheat flour in making breads, pasta, and cookies. A number of research studies have investigated the health-related and nutritional properties of emmer wheat, while comparisons between emmer and common wheat have been shown 2. FLOURS AND BREADS

96

7. EMMER (TRITICUM TURGIDUM SSP. DICOCCUM) FLOUR AND BREAD

to be associated with not only genetic loci affecting these traits, but also environment and genotype by environment interaction effects. This challenge is further complicated by the epigenetic modification—that is, histone modification, noncoding ribonucleic acid (RNA) molecules, and deoxyribonucleic acid (DNA) methylation, which can be altered by environmental stimuli and affects gene and regulation expression. However, the measures that need to be taken into account in any comparative study will have to include field conditions (such as water availability and plant density) and agronomic practices that are favorable to each of these groups, as well as the requirement for reliable phenotypic assessments in the multiyear and multiple-location trials.52 This has been even more challenging in the context of the interactions of genotypes by milling method and genotypes by baking approach, as well as genotypes by environment interaction.53

SUMMARY POINTS • The danger of genetic erosion of crop plants and the potential consequences for agriculture reinforce the need for further exploitation of the unrealized potential of ancestral species like T. turgidum ssp. dicoccum (emmer wheat), the domesticated ancestor of durum and bread wheat, essentially for the improvement of grain protein, fiber, minerals, and phytochemicals. • The recently growing interest in natural and organic products has led to an emmer rediscovery, not only due to its nutritional and healthy properties, but also because it is amenable to low-input and organic farming system. • Emmer flour can fully or partially replace wheat flour in most bakery products, such as bread and pasta. Modern cooks are discovering the full flavors, textures, and nutrition of whole-grain emmer pasta and bread, while they are also exploring new ideas, such as adding emmer grains to dishes such as soups. • Further research is needed to elucidate the physical, chemical, and nutritional properties of emmer grain and to address its beneficial health effects. • The superior tolerance of emmer wheat to environmental and biotic stresses such as pests, pollution, cold, heat, drought, and salinity could help farmers to sustainably manage harsh environments and to meet their subsistence needs without depending on mechanization, chemical fertilizers, pesticides, or modern agricultural processes.

Acknowledgments I would like to thank Dr. S.A.M. Mirmohammadi Maibody for depicting the map of Fertile Crescent and granting the permission to publish this image.

References 1. Arzani A, Ashraf M. Cultivated ancient wheats (Triticum spp.): a potential source of health-beneficial food products. Compr Rev Food Sci Food Saf 2017;16:477–88. 2. Miller BDD, Welch RM. Food system strategies for preventing micronutrient malnutrition. Food Policy 2013;42:115–28. 3. Shewry PR, Pelln TK, Lovegrove A. Is modern wheat bad for health? Nat Plant 2016;2:16097. https://doi.org/10.1038/nplants.2016.97. 4. Nesbitt M, Samuel D. From staple crop to extinction? The archaeology and history of the hulled wheats, In: Padulosi S, Hammer K, Heller J, editors. Hulled Wheats: Proceedings of the 1st International Workshop on Hulled Wheats. Castelvecchio Pacoli, Italy, 21 and 22 July 1995, IPGRI, Rome; 1996. 5. Arzani A, Khalighi MR, Shiran B, Kharazian N. Evaluation of diversity in wild relatives of wheat. Czech J Genet Plant Breed 2005;41:112–7. 6. Salamini F, Ozkan H, Brandolini A, Schafer-Pregl R, Martin W. Genetics and geography of wild cereal domestication in the near east. Nat Rev Genet 2002;3:429–41. 7. Luo MC, Yang ZL, You FM, Kawahara T, Waines JG, Dvorak J. The structure of wild and domesticated emmer wheat populations, gene flow between them, and the site of emmer domestication. Theor Appl Genet 2007;114:947–59. 8. D’Antuono LF. Traditional foods and food systems: a revision of concepts emerging from qualitative surveys on-site in the Black Sea area and Italy. J Sci Food Agric 2013;93:3443–54. 9. D’Antuono LF, Galletti GC, Bocchini P. Fiber quality of emmer (Triticum dicoccum Schubler) and einkorn wheat (T. monococcum L.) landraces as determined by analytical pyroly. J Sci Food Agric 1998;78:213–9. 10. Galterio G, Codianni P, Giusti AM, Pezzarossa B, Cannella C. Assessment of the agronomical and technological characteristics of Triticum turgidum ssp. dicoccum Schrank and T. spelta L. Nahrung/Food 2003;47:54–9. 11. Serpen A, G€ okmen V, Karag€ oz A, K€ oksel H. Phytochemical quantification and total antioxidant capacities of emmer (Triticum dicoccon Schrank) and einkorn (Triticum monococcum L.) wheat landraces. J Agric Food Chem 2008;56:7285–92. 12. Christopher A, Sarkar D, Zwinge S, Shetty K. Ethnic food perspective of North Dakota common emmer wheat and relevance for health benefits targeting type 2 diabetes. J Ethnic Food 2018;5:66–74. https://doi.org/10.1016/j.jef.2018.01.002. 13. Galterio G, Cappelloni M, Desiderio E, Pogna NE. Genetic, technological and nutritional characteristics of three Italian populations of ‘farrum’ (Triticum turgidum ssp. dicoccon). J Genet Breed 1994;48:391–8.

2. FLOURS AND BREADS

REFERENCES

97

14. Cubadda R, Marconi E. Technological and nutritional aspects in emmer and spelt. In: Padulosi S, Hammer K, Heller J, editors. Hulled wheats. Rome: IPGRI; 1995. p. 203–21. 15. Konvalina P, Moudry-jr J, Moudry J. Quality parameters of emmer wheat landraces. J Cent Eur Agric 2008;9:539–46. 16. Galterio G, Hartings H, Nardi S, Motto M. Biochemical and phylogenetic analysis of the major T. turgidum ssp. dicoccum Schrank populations cultivated in Italy. J Genet Breed 2000;54:303–9. 17. Coda R, Nionelli L, Rizzello CG, De Angelis M, Tossut P, Gobbetti M. Spelt and emmer flours: characterization of the lactic acid bacteria microbiota and selection of mixed starters for bread making. J Appl Microbiol 2010;108:925–35. 18. Birdsall JJ. Summary and areas for future research. Am J Clin Nutr 1985;41:1172–6. 19. Anderson JW, Smith BM, Geil PB. High-fiber diet for diabetics: safe and effective treatment. Post Graduate Med 1990;88:157–68. 20. Marconi M, Cubadda R. Emmer wheat. In: Abdel-Aal ESM, Wood P, editors. Speciality grains for food and feed. St. Paul, MN: American Association of Cereal Chemists Inc.; 2005. p. 63–8. 21. Perrino P, Infantino S, Basso P, Di Marzio A, Volpe N, Laghetti G. Valutazione e selezione di farro in ambienti marginali dell’appennino molisano. L’Informatore Agrario 1993;43:41–4. 22. Bouis HE. Micronutrient fortification of plants through plant breeding: can it improve nutrition in man at low cost? Proc Nutr Soc 2003;62:403–11. 23. Cakmak I. Enrichment of cereal grains with zinc: agronomic or genetic biofortification? Plant Soil 2008;302:1–17. 24. Murphy KM, Reeves PG, Jones SS. Relationship between yield and mineral nutrient concentrations in historical and modern spring wheat cultivars. Euphytica 2008;163:381–90. 25. Genc Y, McDonald GK. Domesticated emmer wheat [T. turgidum L. subsp. dicoccon (Schrank) Thell.] as a source for improvement of zinc efficiency in durum wheat. Plant Soil 2008;310:67–75. 26. Ortiz-Monasterio I, Graham RD. Breeding for trace minerals in wheat. Food Nutr Bull 2000;21:392–6. 27. Hidalgo A, Brandolini A. Nutritional properties of einkorn wheat (Triticum monococcum L.). J Sci Food Agric 2014;94:601–12. 28. Lage J, Skovmand B, Pena RJ, Andersen SB. Grain quality of emmer wheat derived synthetic hexaploid wheats. Genet Resour Crop Evol 2006;53:955–62. 29. Leenhardt F, Lyana B, Rocka E, Boussard A, Potus J, Chanliaud E, Remesya C. Genetic variability of carotenoid concentration, and lipoxygenase and peroxidase activities among cultivated wheat species and bread wheat varieties. Eur J Agron 2006;25:170–6. 30. Behall KM, Scholfield DJ, Hallfrisch J. Whole-grain diets reduce blood pressure in mildly hypercholesterolemic men and women. J Am Diet Assoc 2006;106:1445–9. 31. Jacobs DR, Pereira MA, Stumpf K, Pins JJ, Adlercreutz H. Whole grain food intake elevates serum enterolactone. Br J Nutr 2002;88:111–6. 32. Fung TT, Hu FB, Pereira MA, Liu S, Stampfer MJ, Colditz GA, Willett WC. Whole-grain intake and the risk of type 2 diabetes: a prospective study in men. Am J Clin Nutr 2002;76:535–40. 33. Montonen J, Knekt P, Jarvinen R, Aromaa A, Reunanen A. Whole-grain and fiber intake and the incidence of type 2 diabetes. Am J Clin Nutr 2003;77:622–9. 34. Chatenoud L, Tavani A, La Vecchia C, Jacobs DR, Negri E, Levi F, Franceschi S. Whole grain food intake and cancer risk. Int J Cancer 1998;77:24–8. 35. Kasum CM, Nicodemus K, Harnack LJ, Folsom AR. Whole grain intake and incident endometrial cancer: the Iowa women’s health study. Nutr Cancer 2001;39:180–6. 36. Moore J, Hao Z, Zhou K, Luther M, Costa J, Yu LL. Carotenoid, tocopherol, phenolic acid, and antioxidant properties of Maryland-grown soft wheat. J Agric Food Chem 2005;53:6649–57. 37. Mpofu A, Sapirstein HD, Beta T. Genotype and environmental variation in phenolic content, phenolic acid composition, and antioxidant activity of hard spring wheat. J Agric Food Chem 2006;54:1265–70. 38. Lacko-Bartosova M, Curna V. Nutritional characteristics of emmer wheat varieties. J Microbiol Biotechnol Food Sci 2015;4:95–8. 39. Davis KR, Cain RF, Peters LJ, LeTourneau D, McGinnis J. Evaluation of the nutrient composition of wheat. II. Proximate analysis, thiamine, riboflavin, niacin and pyridoxine. Cereal Chem 1981;58:116–20. 40. Brandolini A, Hidalgo A, Moscaritolo S. Chemical composition and pasting properties of einkorn (Triticum monococcum L. subsp. monococcum) whole meal flour. J Cereal Sci 2008;47:599–609. 41. Mohammadkhani A, Stoddard FL, Marshall DR. Survey of amylose content in Secale cereale, Triticum monococcum, T. turgidum and T. tauschii. J Cereal Sci 1998;28:273–80. 42. Regina A, Berbezy P, Kosar-Hashemi B, Li S, Cmiel M, Larroque O, Bird AR, Swain SM, Cavanagh C, Jobling SA, Li Z, Morell M. A genetic strategy generating wheat with very high amylose content. Plant Biotechnol J 2015;13:1276–86. 43. Gebruers K, Dornez E, Boros D, Fra A, Dynkowska W, Bedo Z, Rakszegi M, Delcour JA, Courtin CM. Variation in the content of dietary fiber and components thereof in wheats in the HEALTHGRAIN diversity screen. J Agric Food Chem 2008;56:9740–9. 44. Andersson A, Andersson R, Piironen V, Lampi AM, Nystrom L, Boros D, Fras A, Gebruers K, Courtin CM, Delcour JA, Raskzegi M, Bedo Z, Ward JL, Shewry PR, Aman P. Contents of dietary fibre components and their relation to associated bioactive components in whole grain wheat samples from the HEALTHGRAIN diversity screen. Food Chem 2013;136:1243–8. 45. Loje H, Moller B, Laustsen AM, Hansen A. Chemical composition, functional properties and sensory profiling of einkorn (Triticum monococcum L.). J Cereal Sci 2003;37:231–40. 46. Grausgruber H, Sailer C, Ghambashidze G, Bolyos L, Ruckenbauer P. Genetic variation in agronomic and quantitative traits of ancient wheats. In: Grausgruber H, Ruckenbauer P, editors. Genetic variation for plant breeding: Proceedings of the 17th EUCARPIA General Congress. Vollman J. Vienna: BOKU–University of Natural Resources and Applied Life Sciences; 2004. p. 19–22. 47. Shewry PR, Hawkesford MJ, Piironen V, Lampi A, Gebruers K, Boros D, Andersson AAM, Aman P, Rakszegi M, Bedo Z, Ward JL. Natural variation in grain composition of wheat and related cereals. J Agric Food Chem 2013;61:8295–303. 48. Suchowilska E, Wiwart M, Borejszo Z, Packa D, Kandler W, Krska R. Discriminant analysis of selected yield components and fatty acid composition of chosen Triticum monococcum, Triticum dicoccum and Triticum spelta accessions. J Cereal Sci 2009;49:310–5. 49. Hidalgo A, Brandolini A, Ratti S. Influence of genetic and environmental factors on selected nutritional traits of Triticum monococcum. J Agric Food Chem 2009;57:6342–8. 50. Suchowilska E, Wiwart M, Kandler W, Krska R. A comparison of macro- and microelement concentrations in the whole grain of four Triticum species. Plant Soil Environ 2012;58:141–7.

2. FLOURS AND BREADS

98

7. EMMER (TRITICUM TURGIDUM SSP. DICOCCUM) FLOUR AND BREAD

51. Zhao FJ, Su YH, Dunham SJ, Rakszegi M, Bedo Z, McGrath SP, Shewry PR. Variation in mineral micronutrient concentrations in grain of wheat lines of diverse origin. J Cereal Sci 2009;49:290–5. 52. Shewry PR, Hey S. Do “ancient” wheat species differ from modern bread wheat in their contents of bioactive components? J Cereal Sci 2015;65:236–43. 53. Kucek LK, Dyck E, Russell J, Clark L, Hamelman J, Leader SB, Senders S, Jones J, Benscher D, Davis M, Roth G, Zwinger S, Sorrells ME, Dawson JC. Evaluation of wheat and emmer varieties for artisanal baking, pasta making, and sensory quality. J Cereal Sci 2017;74:19–27.

2. FLOURS AND BREADS