**2. Mechanism in the germination of cereals**

Cereal beta-amylase is best known for the vital role it plays in the release of easily fermentable sugars from corn starch cereals to feed the production of alcohol by yeasts in beer brewing investigated because of its importance in this economically important brewing industry. Beta-amylases cereals are also used in other products of the food industry and in the analysis of starch. They are markers in the evaluation of cereals and in grain development studies. The enzymes β-amylases of cereals have been little studied at the physiological level.

In recent times, it was discovered that there are two categories of β-amylases, according to their pattern of tissue and taxonomic and physiological development. The classical β-amylases are present in the endosperm of the cereals of the family Triticeae of the subfamily Festucoideae of the grasses and the high levels of enzymatic activity, while the others are distributed in all tissues of the cereal but show less activity. The physiological phenomenology and the use of grain betaamylases are discussed in relation to these two categories of enzymes [7]. The life

**135**

aspartic proteinases [23].

**3. Arabinoxylans and viscosity in the process of malting**

Rye contains considerably higher amounts of arabinoxylans (AX), especially water-extractable arabinoxylans (WEAX), than barley. The rye AX structure and its properties were described [24]. AX are cell wall non-starch polysaccharides and are constituted by a chain of β-1,4 units of xylopyranose. The α-arabinofuranose chain can bind to the C(O)-2 and/or C(O)-3 of the xylose residues. It contains some arabinose substituents that are esterified with ferulic acid in C(O)-5 [25]. The molecular masses, the degree and the configuration of the arabinose branching, and the degree of esterification with ferulic acid exert an important influence on the properties of the AX. Since WEAX can bind to many water molecules, it can change the viscosity of the solutions making them more consistent. Gels can be formed by oxidative cross-linking of AX macromolecules through ferulic acid residues. The AX of the rye grains, during the process of the germination, suffer an enzymatic degradation. The inner bonds of the main chain of the xylan are divided forming a greater quantity of shorter-chain AX molecules by the action of

*Fibers: Healthy Component in Whole Wheat and Rye Flours*

cycle of a grain of cereal is divided into stages of development and germination, divided by a latency period [8]. During germination, much of the amino acid supply necessary for the growth of emerging seedlings comes from the degradation of the storage proteins of the seeds. The latter are synthesized during the maturation of the seeds and are deposited in specialized vacuoles. Little is known about the proteolytic enzymes in germinated rye. In contrast, the proteases that appear during the germination of barley [9–11] and wheat [12] are well studied. Using a non-denaturing electrophoretic system with protein substrate incorporated in the gel, [13] detected seven proteolytic bands in green barley malt. Five of these bands were maximally active at pH 3.8. Up to 20 proteolytic bands could be detected in extracts of germinated wheat grains [14]. The information shows that the total proteolytic activity increases during germination [15] has been investigated the temporal pattern of appearance of proteinases during germination, the sensitivities to specific inhibitors, and the location of proteinases and separated 42 activities into the germinating grain of barley using two-dimensional (2-D) gel electrophoresis (IEF × PAGE). These substances were divided into five groups based on isoelectric point (pI) values, PAGE mobilities, and biochemical characteristic [16]. About twothirds of these enzymes were cysteine proteinases. The barley cysteine proteinases apparently hydrolyze most of the hordes, which are the main storage proteins of the barley endosperm. The purification and characterization of some of these cysteine proteinases have been described in several reports [17–20]. In [21] initiated the characterization of proteases in malted rye using two different methods to analyze their activities. A qualitative 2D method was used to measure the heterogeneity of the proteases and a method with solutions of different substrates to measure the activities of the different proteinase groups. It was concluded that the selected Humbolt rye cultivar produces high levels of proteolytic activities [22]. It was germinated under optimal conditions of temperature, aeration, and humidity, and the proteolytic activities were monitored using capillary electrophoresis methods. The total proteolytic activity was significantly higher after soaking and increased during the first 3 days of germination, but not after that time. The hydrolyzing activity was maximal at pH 53.5 and 45–50°C. After grinding, there were marked increases in the levels of proteolytic activity. The use of specific inhibitors showed the presence of four kinds of proteinases. According to the precedents, it is evident that hydrolysis of storage proteins in rye during germination is probably due to cysteines and

*DOI: http://dx.doi.org/10.5772/intechopen.83341*

#### *Fibers: Healthy Component in Whole Wheat and Rye Flours DOI: http://dx.doi.org/10.5772/intechopen.83341*

*Food Engineering*

attention.

introduced to intestine. The intestinal microflora ferments prebiotics. Prebiotics saccharide belonging to the inulin group, GlcpFruf [α-d-fructopyranosyl-(β-dfructofuranosyl) n-1-d-fructofuranose], Frup-Fruf [β-d-fructopyranosyl-(β-dfructofuranosyl) n-1-d-fructofuranose] where n = 10–60; fructooligosaccharides, FOS (apart from oligofructose with n = 2–9 and, eventually, d-glucose, d-xylose, d-galactose and mannose residues) and non-digestible sugars, NDO. The oligofructose is present in wheat, onion, garlic, endive, leeks, asparagus, and others. In breast milk, the levels of oligosaccharides are relatively high, from 3 to 6 g/L; bifidobacterium selectively digests FOS and NDO and stimulates the development of colonies. Babies fed by the formula, that is, that refers to prebiotics, promote the development of probiotic bacteria, which inhibit the growth of pathogenic bacteria, the bacterial digestion of nutrients, especially proteins, and the decrease of their allergenicity. Probiotic bacteria synthesize cytoprotective short-chain acids, B and K vitamins, and polyamines and degrade the fiber by improving the action of the

Arabinoxylans (AX) (sometimes called pentosans) are the main non-cellulosic polysaccharides that are abundant in cereals. In the wheat and rye, they differ in their solubility in water, being some soluble and some others insoluble. Watersoluble and water-insoluble fractions are separated through stirring and from a centrifugation. These compounds have healthy benefits. The health benefits are prebiotic effect together with their ability antioxidant. This properties makes these are prevention agents of the colon cancer disease. At the metabolic level, the AX control glycemic and cholesterol levels are also immune regulator agents. During the later years, the research and interest of the AX have gathered considerable

Arabinoxylans are composed of a chain, β(1–4) of xylose units, with variable branches of arabinose in (1–2) or (1–3) [3]. The solubility is modified according to the degree of substitution. The smaller the number of lateral branches, the greater the insolubility of the AX and the possibility of generating insoluble complexes [4]. The AX form viscous solutions with pseudoplastic behavior, and in the presence of certain oxidizing agents, the gels are much stronger and stable. This involves the action of ferulic acid in the formation of cross-links between the AX chains [5]. The texture of the bread increases during the cooking due to the crosslinking of the AX, whose natural levels in the wheat flour determine the quality of

Cereal beta-amylase is best known for the vital role it plays in the release of easily

fermentable sugars from corn starch cereals to feed the production of alcohol by yeasts in beer brewing investigated because of its importance in this economically important brewing industry. Beta-amylases cereals are also used in other products of the food industry and in the analysis of starch. They are markers in the evaluation of cereals and in grain development studies. The enzymes β-amylases of cereals have

In recent times, it was discovered that there are two categories of β-amylases, according to their pattern of tissue and taxonomic and physiological development. The classical β-amylases are present in the endosperm of the cereals of the family Triticeae of the subfamily Festucoideae of the grasses and the high levels of enzymatic activity, while the others are distributed in all tissues of the cereal but show less activity. The physiological phenomenology and the use of grain betaamylases are discussed in relation to these two categories of enzymes [7]. The life

colon and by increasing the volume of feces [2].

the bread, in the functional and nutritious properties [6].

**2. Mechanism in the germination of cereals**

been little studied at the physiological level.

**134**

cycle of a grain of cereal is divided into stages of development and germination, divided by a latency period [8]. During germination, much of the amino acid supply necessary for the growth of emerging seedlings comes from the degradation of the storage proteins of the seeds. The latter are synthesized during the maturation of the seeds and are deposited in specialized vacuoles. Little is known about the proteolytic enzymes in germinated rye. In contrast, the proteases that appear during the germination of barley [9–11] and wheat [12] are well studied. Using a non-denaturing electrophoretic system with protein substrate incorporated in the gel, [13] detected seven proteolytic bands in green barley malt. Five of these bands were maximally active at pH 3.8. Up to 20 proteolytic bands could be detected in extracts of germinated wheat grains [14]. The information shows that the total proteolytic activity increases during germination [15] has been investigated the temporal pattern of appearance of proteinases during germination, the sensitivities to specific inhibitors, and the location of proteinases and separated 42 activities into the germinating grain of barley using two-dimensional (2-D) gel electrophoresis (IEF × PAGE). These substances were divided into five groups based on isoelectric point (pI) values, PAGE mobilities, and biochemical characteristic [16]. About twothirds of these enzymes were cysteine proteinases. The barley cysteine proteinases apparently hydrolyze most of the hordes, which are the main storage proteins of the barley endosperm. The purification and characterization of some of these cysteine proteinases have been described in several reports [17–20]. In [21] initiated the characterization of proteases in malted rye using two different methods to analyze their activities. A qualitative 2D method was used to measure the heterogeneity of the proteases and a method with solutions of different substrates to measure the activities of the different proteinase groups. It was concluded that the selected Humbolt rye cultivar produces high levels of proteolytic activities [22]. It was germinated under optimal conditions of temperature, aeration, and humidity, and the proteolytic activities were monitored using capillary electrophoresis methods. The total proteolytic activity was significantly higher after soaking and increased during the first 3 days of germination, but not after that time. The hydrolyzing activity was maximal at pH 53.5 and 45–50°C. After grinding, there were marked increases in the levels of proteolytic activity. The use of specific inhibitors showed the presence of four kinds of proteinases. According to the precedents, it is evident that hydrolysis of storage proteins in rye during germination is probably due to cysteines and aspartic proteinases [23].
