Functional Foods and Dietary Supplements

Processing Effects and Health Benefits

Athapol Noomhorm, Imran Ahmad, Anil Kumar Anal, Athapol Noomhorm, Imran Ahmad, Anil Kumar Anal

• Publisher: Wiley-Blackwell
• Year: 2014
• Print ISBN:
  9781118227879
• eBook ISBN:
  9781118227824
• Edition: 1
• Topic: Tecnologia e ingegneria
• Subtopic: Scienze dell'alimentazione

Functional foods are foods which contain bioactive components, either from plant or animal sources, which can have health benefits for the consumer over and above their nutritional value. Foods which have antioxidant or cancer-combating components are in high demand from health conscious consumers: much has been made of the health-giving qualities of fruits and vegetables in particular. Conversely, foods which have been processed are suffering an image crisis, with many consumers indiscriminately assuming that any kind of processing robs food of its "natural goodness". To date, there has been little examination of the actual effects – whether positive or negative – of various types of food processing upon functional foods.

This book highlights the effects of food processing on the active ingredients of a wide range of functional food materials, with a particular focus on foods of Asian origin. Asian foods, particularly herbs, are becoming increasingly accepted and demanded globally, with many Western consumers starting to recognize and seek out their health-giving properties. This book focuses on the extraction of ingredients which from materials which in the West are seen as "alternative" - such as flour from soybeans instead of wheat, or bran and starch from rice – but which have long histories in Asian cultures. It also highlight the incorporation of those bioactive compounds in foods and the enhancement of their bioavailability.

Functional Foods and Dietary Supplements: Processing Effects and Health Benefits will be required reading for those working in companies, research institutions and universities that are active in the areas of food processing and agri-food environment. Food scientists and engineers will value the new data and research findings contained in the book, while environmentalists, food regulatory agencies and other food industry personnel involved in functional food production or development will find it a very useful source of information.

II
Major Sources of Functional Foods

3
Processing Effects on Functional Components in Cereals and Grains

Binod K. Yadav and J. Jerish Joyner

Indian Institute of Crop Processing Technology, Thanjavur, Tamilnadu, India

3.1 Introduction

Food not only satisfies hunger, it provides necessary nutrients, prevent nutrition-related diseases and improve physical and mental well-being (Nothlings et al., 2007; Takachi et al., 2008). Awareness of the functionality of certain foods and their benefits to human health is growing daily.

Foods or food components beneficial to human health and wellbeing are known as functional foods or functional components. The term functional food was first introduced in Japan in the mid-1980s and refers to processed food containing ingredients that aid specific bodily functions in addition to being nutritious. To date, Japan is the only country that has formulated a specific regulatory approval process for functional food. The Institute of Medicine's Food and Nutrition Board (IOM/FNB) defined functional food as ‘any food or food ingredient that may provide a health benefit beyond the traditional nutrients it contains’ (Hasler, 2002). Health Canada defines functional food as a product that resembles traditional food but possesses demonstrated physiological benefits (Shahidi, 2009).

Functional food comprises:

• conventional food containing naturally occurring bioactive substances (e.g., dietary fibre),
• food enriched with bioactive substances (e.g., probiotics, antioxidants),
• synthesized food ingredients introduced to traditional food (e.g. prebiotics).

Functional food and components are thought to provide benefits beyond basic nutrition and may play a role in reducing or minimizing the risk of certain diseases. Examples of these foods include fruits and vegetables, whole cereal grains, fortified foods and beverages and some dietary supplements. Functional characteristics of many traditional foods are being discovered and studied, while new food products are being developed to include beneficial components. Most important functional foods are made with cereals and grains as the base and have been modified to provide health benefits over and above basic nutrition, keeping a similar appearance to conventional foods that are intended to be consumed as part of a normal diet (Roberfroid, 2000).

Among all the sources of functional foods, cereals, grains and legumes are important economic commodities worldwide. Cereals are grown in over 73% of the total harvested area of the world. They contribute over 60% of the world's food production providing the dietary fibre, proteins, energy, minerals and vitamins required for human health as well as functional components such as phytoestrogens of the lignan family and several phenolic acids with antioxidant properties (Charalampopoulos et al. 2002). In recent years, cereals have been investigated for their potential use in developing functional foods. Cereals contain dietary fibres (β-glucan and arabinoxylan) and carbohydrates (resistant starch and oligosaccharides – galacto- and fructo-oligosaccharides) can also be used as fermentable substrates for the growth of probiotic microorganisms (Charalampopoulos et al. 2002). The contents of some cereals exhibit protective effects such as preventing cancer and cardiovascular disease and reducing tumor incidence; lowering blood pressure, the risk of heart disease, cholesterol and the rate of fat absorption; delaying gastric emptying and supplying gastrointestinal health (Chaturvedi et al., 2011).

Several studies have reported the effects of storage and processing of raw materials on the nutrient content and bioprotective components of functional foods. Normally, processing operations reduce the content of these nutrients and bioprotective substances (Truswell, 2002).

Functional foods are commonly made from rice, corn, soybean and legumes. Functional foods based on cereal and grains are increasingly pouring in to stores despite their ambiguous health benefits. Understanding the nature of the functional components of cereals and legumes is essential for the development of functional food products. Therefore, in this chapter we attempt to provide collective information on the nutrients and bioactive substances in rice, corn, soybean and legumes.The effects of different processing conditions on functional components are also discussed.

3.2 Functional components in cereals and grains

The major cereals considered in the discussion are rice, corn, soybean and legumes in general.

3.2.1 Functional components in rice and their health benefits

Rice is an important source of energy, protein and components with versatile functional properties (Mazza, 1998). Rice proteins are considered valuable because they are colourless, bland, hypoallergenic and hypocholesterolaemic (Ju et al., 2001). The rice kernel comprises 20% hull, 8–12% bran and embryo and 70–72% endosperm or milled rice based on the degree of milling. Rice kernel bran has often been reported for its functional components.

Rice bran

Bran is one of the most abundant co-products produced in the rice milling industry. It contains a high concentration of nutritional compounds, including edible lipids and other phytochemicals that exhibit health benefits (Khuwijitjaru et al., 2007). It is evident from Table 3.1 that rice bran and various co-products make it a valuable ingredient in developing functional food formulations. Major components of bran used for developing functional foods are rice bran oil, defatted rice bran and rice bran enzymatic extract (RBEE).

Table 3.1 Functional components present in rice bran and their health benefits

Rice bran oil

The rice bran contains almost 12–18.5% oil. It contains a range of fats, of which 47% are monounsaturated, 33% polyunsaturated, and 20% saturated. Also it contains highly unsaponifiable components of around 4.3%. This fraction contains functional components like tocotrienols (a form of vitamin E), gamma oryzanol, and beta-sitosterol. These components are very powerful antioxidants (Godber and Wells, 1994). Rice bran oil has a higher tocol concentration (196–219 mg/kg) compared to brown rice (46.4–65.0 mg/kg) (Aguilar-Garcia et al., 2007).

Rice bran enzymatic extract (RBEE)

RBEE is a water-soluble compound which contains proteins, carbohydrates, fat, vitamins and minerals (Parrado et al., 2006). The main component of RBEE is protein (38.1%) in the form of peptide. This high bioabsorbable protein can be used for making protein-enriched diet formulations. RBEE also contains free amino acids of which 6% are sulfur amino acids which contribute to its antiproliferative activity (Parrado et al., 2006).

Defatted rice bran

Rice bran, due to its lipid content, is prone to oxidation resulting in losses of its nutrients and phytochemicals.The deterioration and decrease of nutritional value is a major threat due to rapid oxidation, especially when raw bran is stored in large quantities and used in small amounts. Therefore, rice bran is defatted and dried in order to preserve and store it for a long period without maintaining a low temperature. After heat treatment to remove the oil, rice bran is designated as heat-stabilized defatted rice bran (HSDRB) (Tang et al., 2003). The defatted residues of bran contain 15.4% protein (Hamada, 2000). This protein can be used as a nutraceutical and functional food ingredient (Tang et al., 2003).

The stabilized rice bran may be used directly or the functional components extracted from the bran can be used for functional food formulations. The use of rice for developing functional food has already been explained by several researchers (Prakash and Ramaswamy, 1996; Ye Xudong et al., 2000, Jiamyangyuen et al., 2005; Parrado et al., 2006).

3.2.2 Functional components in corn and their health benefits

Corn (Zea mays), also called maize, is a good source of many nutrients including thiamine (vitamin B₁), pantothenic acid (vitamin B₅), vitamin C, folate, phosphorus and manganese. Apart from these it also possesses several functional components like carotenoids, phenolic acids, dietary fibres, phytosterols and phytostanols which contribute to its abundant functional and health benefits (Table 3.2).

Table 3.2 Functional components present in corn and their health benefits

Corn controls the level of homocysteine, an intermediate product in an important metabolic process called the methylation cycle in the human body. Homocysteine is directly responsible for damage of blood vessels, heart attack, and stroke or peripheral vascular disease. Corn is also a go...

Table of contents

• Cover
• Title Page
• Copyright Page
• Contents
• List of Contributors
• Preface
• I: Fundamentals of Functional Food Processing
• II: Major Sources of Functional Foods
• III: Processing Effects on the Functional Components during Product Development
• IV: Health Benefits and Bioavailability of Functional Foods
• Index
• End User License Agreement