**4.1 Macronutrients**

Maize provides approximately 1400 Kcal/100 g (on a dry basis) of energy that is sufficient to maintain the equilibrium. This energy is also used to perform different types of physiological task. Maize or corn can be consumed as a source of energy in the form of breakfast cereals as cornflakes, chapattis, tortillas, etc. Maize also contains an appreciable amount of fat content that helps in the carrier of fat-soluble vitamins A, D, E and K. The presence of fat in maize or corn is responsible for much of the texture and flavour of food. Thus it helps in increasing the palatability.

The fat content beneath the skin known as the subcutaneous fat also serves as an insulating material for the body and is effective in preventing heat loss. Moreover, fat content also acts as a body reservoir for energy conservation purpose.

Another important component in maize after fat is dietary fibre and is defined as the portion of food derived from plant cell, which is resistant to hydrolysis or digestion by the elementary enzyme system in human beings. However, some of the bacteria in the large intestine can degrade some components of fibre releasing products that can be absorbed into the body and also used as a source of energy. Crude fibre is the residue remaining after the treatment with hot sulphuric acid, alkali and alcohol. The major component of crude fibre is a polysaccharide called cellulose and a part of dietary fibre. Insoluble fibres are indigestible and insoluble in water, while soluble fibres are indigestible but soluble in water. Total fibre is the sum of insoluble and soluble fibres. Dietary fibre is isolated and extracted from a synthetic fibre that has proven health benefits. Resistant starch also functions as dietary fibre [6–8].

Total fibre = dietary fibre + functional fibre

The effect of fibre on the gastrointestinal tract (**Table 1**) is influenced by the characteristics of the fibre itself, the particle size, the interaction between fibre and other dietary components and the bacteria flora. Maize also contains a significant quantity of insoluble fibre found in the cell wall of the constituent [9].

The insoluble fibre present in maize or corn has a physiological effect in preventing constipation, diverticulitis and even cancer of the large intestine as presented in **Table 2**.

Maize is also considered as a booster of nutrient like carbohydrates, fats, proteins and insoluble fibres that helps in providing sufficient energy to meet the human daily dietary requirements [10]. The proximate composition of maize is presented in **Table 3**.

#### *4.1.1 Protein*

Maize contains 8–11% of protein that is made from different components like albumin, globulin, nonnitrogen substance, prolamin, etc. The quality of maize protein depends upon its agronomic practices and genotype as well. The quality of maize protein is not of good quality as compared to other cereal grains like rice, wheat, barley, etc. Recent researches have shown that with genetic modification, the quality of maize protein can be improved. The maize protein is known as zein that is lack of essential amino acids tryptophan and lysine. The opaque-2 gene is also helpful in reducing the concentration of zein up to 30% and improves the quality protein maize (QPM). The protein content present in maize helps in the growth


**23**

**Table 3.**

detoxification as well.

*4.1.2 Essential amino acids*

and maintenance of tissues, formation of essential body compounds, transport of nutrients, regulation of water balance, maintenance of appropriate pH, defence and

These amino acids cannot be synthesised by the body at a sufficient rate to meet the body requirement for optimum growth and development. The human body has certain limited powers of converting one amino acid into another. This is

*Nutritive Value*

Constipation Diverticulitis

Varicose veins Haemorrhoids

Cancer of the large intestine

*Source: Raninen et al. [9].*

**Table 2.**

Irritable bowel syndrome

*DOI: http://dx.doi.org/10.5772/intechopen.88963*

**Disease Physiological mechanism**

• Increase the water-holding capacity

• Decreases intracolonic pressure

• Increases binding of intestinal bile acids

• Fibre-induced effects on faecal enzymes

**S. no. List of nutrients Nutritive value\*** Moisture 9.26 ± 0.55 Protein (g) 8.80 ± 0.49 Ash (g) 1.17 ± 0.16 Fat (g) 3.77 ± 0.48 Total fibre (g) 12.24 ± 0.93 Insoluble fibre (g) 11.29 ± 0.85 Soluble fibre (g) 0.94 ± 0.18 Carbohydrates (g) 64.77 ± 1.58 Energy (KJ) 1398 ± 25

• Increases on bile acids and mutagens in the colon • Adsorbing cancer-producing hydrocarbons

• Increases stool weight and volume • Increases frequency of defaecation

pH modifications

*Source: Longvah et al. [6], Indian Food Composition Tables, Government of India.*

*\*All the values are presented as per 100 grammes of edible portion.*

*Nutritive value of proximate content of maize, dry (*Zea mays*).*

*Role of dietary fibre in preventing and managing diseases.*

• Volatile fatty acids which are released by bacteria having a laxative effect

• Food residues remain in the colon for less time for carcinogen to be absorbed

• Bulk and water of the faeces may dilute the carcinogen to a nontoxic level

• Production and distribution of short-chain fatty acids in the colon resulting in

• Faster bowel emptying due to increased intraluminal mass bulk

• Changes in the population of microbes in the GI tract

• Increases the stool weight • Reduces the transit time • Enhances gastric motility

#### **Table 1.**

*Influence of dietary fibre on the gastrointestinal tract.*


#### **Table 2.**

*Maize - Production and Use*

presented in **Table 2**.

presented in **Table 3**.

**Site Activity**

*Influence of dietary fibre on the gastrointestinal tract.*

Mouth Stimulate saliva secretion

Stomach Dilutes contents, delays gastric emptying Small intestine Dilutes content, delay absorption

*4.1.1 Protein*

The fat content beneath the skin known as the subcutaneous fat also serves as an insulating material for the body and is effective in preventing heat loss. Moreover,

Total fibre = dietary fibre + functional fibre

The effect of fibre on the gastrointestinal tract (**Table 1**) is influenced by the characteristics of the fibre itself, the particle size, the interaction between fibre and other dietary components and the bacteria flora. Maize also contains a significant

The insoluble fibre present in maize or corn has a physiological effect in preventing constipation, diverticulitis and even cancer of the large intestine as

Maize is also considered as a booster of nutrient like carbohydrates, fats, proteins and insoluble fibres that helps in providing sufficient energy to meet the human daily dietary requirements [10]. The proximate composition of maize is

Maize contains 8–11% of protein that is made from different components like albumin, globulin, nonnitrogen substance, prolamin, etc. The quality of maize protein depends upon its agronomic practices and genotype as well. The quality of maize protein is not of good quality as compared to other cereal grains like rice, wheat, barley, etc. Recent researches have shown that with genetic modification, the quality of maize protein can be improved. The maize protein is known as zein that is lack of essential amino acids tryptophan and lysine. The opaque-2 gene is also helpful in reducing the concentration of zein up to 30% and improves the quality protein maize (QPM). The protein content present in maize helps in the growth

Large intestine Dilutes contents, forms substrate for bacteria, traps water, binds cation, soften stools, prevents straining

fat content also acts as a body reservoir for energy conservation purpose. Another important component in maize after fat is dietary fibre and is defined as the portion of food derived from plant cell, which is resistant to hydrolysis or digestion by the elementary enzyme system in human beings. However, some of the bacteria in the large intestine can degrade some components of fibre releasing products that can be absorbed into the body and also used as a source of energy. Crude fibre is the residue remaining after the treatment with hot sulphuric acid, alkali and alcohol. The major component of crude fibre is a polysaccharide called cellulose and a part of dietary fibre. Insoluble fibres are indigestible and insoluble in water, while soluble fibres are indigestible but soluble in water. Total fibre is the sum of insoluble and soluble fibres. Dietary fibre is isolated and extracted from a synthetic fibre that has proven health

benefits. Resistant starch also functions as dietary fibre [6–8].

quantity of insoluble fibre found in the cell wall of the constituent [9].

**22**

**Table 1.**

*Source: Raninen et al. [9].*

*Role of dietary fibre in preventing and managing diseases.*


*Source: Longvah et al. [6], Indian Food Composition Tables, Government of India. \*All the values are presented as per 100 grammes of edible portion.*

#### **Table 3.**

*Nutritive value of proximate content of maize, dry (*Zea mays*).*

and maintenance of tissues, formation of essential body compounds, transport of nutrients, regulation of water balance, maintenance of appropriate pH, defence and detoxification as well.

### *4.1.2 Essential amino acids*

These amino acids cannot be synthesised by the body at a sufficient rate to meet the body requirement for optimum growth and development. The human body has certain limited powers of converting one amino acid into another. This is


*Source: Longvah et al. [6], Indian Food Composition Tables, Government of India. \*All the values are presented as per 100 grammes of edible portion.*

#### **Table 4.**

*Essential and non-essential amino acid profile (g) of maize, dry (*Zea mays*).*

achieved in the liver by the process of transamination, whereby an amino group is shifted from one molecule to another under the influence of amino transferases, the coenzyme of which is pyridoxal phosphate. The inability to synthesize the carbon skeleton of these amino acids is the probable reason why they are dietary essentials. There are nine essential amino acids that are required for a human body to perform various functions (**Table 4**).
