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International Journal of Multidisciplinary Research and Development
International Journal of Multidisciplinary Research and Development
Online ISSN: 2349-4182, Print ISSN: 2349-5979
Impact Factor: RJIF 5.72
Volume 5; Issue 4; April 2018; Page No. 05-08
Brown rice: Nutrition and health claims
Tahiya Qadri1, Tabasum Fatima2, Bazila Beenish3, Gousia Gani4, Qudsiya Ayaz5
2 Assistant Professor, Kashmir Tibbiya College, Hospital and Research Centre, Jammu & Kashmir, India
1, 3, 4, 5 Ph. D Scholar, Division of Food Science and Technology, SKUAST Kashmir, Jammu & Kashmir, India
Rice is the most important dietary staple cereal crop, especially for people living in Asian subcontinent. Rice consumers eat white
rice and consider brown rice as food for the farmers, the poor, and for the animals. White rice is associated with beriberi, a
potentially fatal disease due to lack of thiamine (vitamin B1), because this essential vitamin is stripped out of the rice during
processing. Today people are going for whole food, like our fore father used to eat. Brown rice is a rice source of minerals and
dietary fibre that support the normal functioning of human body. This review covers nutritional composition and various biological
activities of brown rice in aspects to human health. Such biological activities which are related to rice and its products are lowering
cholesterol, reducing blood pressure and preventing colorectal cancer.
Keywords: staple, thiamine dietary fibre, colorectal cancer
In some parts of the world, the word "to eat" means "to eat
rice." Rice is the staple food of more than 39 countries which
accounts for nearly half of the world’s population. All
varieties of rice are present throughout the year supplying as
much as half of the daily calories to half of the population
(Babu et al., 2009). Rice contributes the greatest percentage of
calories (22%) and proteins (17%) to populations living
mostly in developing countries (Vetha et al., 2013).
Rice is a unique crop due to its soft taste, low sodium levels,
easy digestible carbohydrates and hypoallergenic properties
(Mir et al., 2015) [15]. Rice is consumed, as such in the form of
whole grain or is milled to obtain flour. Rice milling involves
two steps viz hulling and polishing. During polishing 15% of
protein, 85% of the fat, 90% of the calcium, 75% of the
phosphorus, 80% of thiamine, 70% of riboflavin and 68% of
niacin are removed. By discarding the bran of rice, we are
discarding a bag of benefits that helps us to grow (Vetha et al.,
Problems associated with consumption of white rice
Low energy and protein intakes are common nutritional
problems for people in rice consuming countries. According to
UNICEF (1991) [24], incidence of low birth weight, infant
mortality, mortality of children under five years of age, and
prevalence of underweight children are considerably higher in
rice consuming countries than in other countries. An article
published in Rice Today (Jan, 2004) [19] reported that
micronutrient deficiencies of global public health concern
include nutritional anaemia due to iron deficiency, vitamin A
deficiency in children, vitamin B1 (thiamine) deficiency and
iodine deficiency disorders which are common in many
countries where rice is the staple food. (Dipti et al., 2012) [8].
Iron deficiency anaemia is a worldwide public health problem,
with global prevalence estimated to be 24.8% (Shaw et al.,
2011) [22]. The majority of disease burden is shouldered by
developing countries with high levels of rice consumption.
One reason for iron deficiency in rice consuming population is
due to the low concentration of iron in polished rice
(Bounphanousay 2007) [6].
Brown Rice
Brown rice is unpolished whole grain produced by removing
only the hull or husk using a mortar and pestle or rubber rolls.
It may be distinctly brown, reddish or purplish. The embryo
may or may not be left intact depending on the hulling
process. It becomes milled or white rice when the bran layer is
stripped off in the milling or 'whitening' process. It has a mild
nutty flavour, is chewier than white rice and becomes rancid
more quickly, but is far more nutritious (Anonymous, 2000)
[1]. Post-harvest researchers have reported that the milling
recovery in brown rice is 10% higher than the polished rice
(Garrow et al., 2000).
Brown rice is distinct from other cereal grains in its content of
tocotrienols-t ocopherols, γ-oryzanol, and β-sitosterol. These
constituents decrease the concentrations of total plasma
cholesterol, triglycerides, and low-density lipoproteins and
increase the concentrations of high-density lipoproteins.
Brown rice also contain soluble dietary fibres -glucan,
pectin, and gum) and ferulic acid from nonlignified cell walls.
(Ryan, 2011) [20]. Recent studies have shown that brown rice
has a wide range of biological activities, including
antioxidant, anti-carcinogenic, antiallergenic activities, anti-
atherosclerosis and amelioration of iron deficiency anaemiain
the body (Mir et al., 2015) [15]. In addition to this, brown rice
has the ability to fight heart diseases and cancer (Kuhns and
Coulter, 2009) [14]. For people living with celiac disease, it is
one way that they can consume breads and other bakery goods
due to the absence of gluten forming proteins in brown rice
(Morita, 2007) [16].
International Journal of Multidisciplinary Research and Development
Thus, consumption of brown rice is a way forward to exploit
its nutritive power to the fullest in order to overcome the
nutritional disorder suffered by most of the population. Now a
day’s nutritionist and dieticians are increasingly
recommending brown rice as an excellent source of all-round
Besides the nutritional benefits of consuming brown rice,
there are two economic importance (Vetha et al., 2013):
1. Polishing and whitening reduces the power demand of
milling by as much as 65%.
2. With the bran and the nutrient-rich embryo intact, and
with fewer broken grains, whole grain milling recovery is
as much as 10% higher than white rice.
Brown rice is superior to polished rice
Our food ranking system identifies brown rice as an excellent
source of manganese and agood source of the minerals like
selenium and magnesium (Pankaj, 2008) [17]. Brown rice has
protein content twice that of white rice. Brown rice is also
high in silica (6 mg/g), probably because of the presence of
rice hull fragments (Seki et al., 2005) [21].
Rice bran fraction (a part of brown rice) produces two major
components, namely rice bran oil and defatted rice bran. A
breakdown component from rice bran oil consists a number of
fatty acids and flavonoid content. Brown rice oil contains 20%
unsaturated fatty acids in the form of oleic, and lino lenic fatty
acids. Meanwhile, defatted rice bran component consist of a
number of polysaccharides and dietary fibre that support
cancer and cardiovascular diet therapy (Henderson et al.,
2012) [10].
Table 1: Comparison of calorific value and nutrient content of brown
rice and white rice
Brown Rice
White Rice
4.88 g
4.10 g
49.7 g
49.6 g
1.17 g
0.205 g
Dietary Fibre
3.32 g
0.74 g
Thiamine (B1)
0.223 mg
0.176 mg
Riboflavin (B2)
0.039 mg
0.021 mg
Niacin (B3)
2.730 mg
2.050 mg
Vitamin B6
0.294 mg
0.103 mg
10 mcg
4.1 mcg
Vitamin E
1.4 mg
0.462 mg
72.2 mg
22.6 mg
142 mg
57.4 mg
137 mg
57.4 mg
26 mg
19 mg
1.05 mg
0.841 mg
Source: Vetha et al., 2013
Difficulties of brown rice
After the bran layer is removed from the endosperm during
milling, the individual cells are disrupted, and the rice bran
lipids come into contact with a highly reactive enzyme
(lipase). The bran contains oil composed of glycerides, about
2-3% of unsaturated Fatty Acids (UFA) and 1.6%
phospholipids. Double bonds of unsaturated Fatty Acids are
susceptible to oxidation, forming oxides and peroxides
causing rancidity (Vetha et al., 2013).
Freshly milled rice bran has a short shelf life because of
decomposition of lipids into free fatty acids (FFA) (hydrolytic
rancidity), making it unsuitable for human consumption and
the economical extraction of edible rice oil. In rice bran, the
hydrolysis is catalysed by endogenous enzyme activity
(lipases) and, to some extent, by microbial enzymes if the
material is of poor quality (Barnesand Galliard, 1991).The
hydrolysis of lipids in rice bran becomes apparent in several
ways: off-flavour such as a soapy taste, increased acidity,
reduced pH, changes in functional properties, and increased
susceptibility of fatty acids to oxidation.
Health benefits of brown rice
Numerous studies have been conducted, which correlates,
bioactive compounds in brown rice such as γ-oryzanol,
tocopherols, tocotrienols, polyphenols, phytosterols, and
carotenoids, found with health benefit effects. It also contains
essential amino acids and micronutrients that work together
for health promotion. Selected compounds from brown rice
have been investigated for the prevention and control of
chronic disease through multiple mechanisms. Brown rice and
its oil have reported cardiovascular health benefits (Cara et al.,
1992) [7].
Brown rice helps in lowering of cholestrol
Brown rice includephytosterols, triterpene alcohols,
tocopherols, and tocotrienols, as possible hypocholesterolemic
agents. The cholesterol-lowering properties ofbrown riceis a
result ofunsaponifiable component present in rice bran oil
(Wilson et al., 2000) [27]. Replacing the usual cooking oils
with rice bran oil decreases the blood cholesterol’s level in
hyper cholesterol patients (Raghuram et al., 1989).
Brown rice helps prevent cancer
Brown rice can substantially reduce the risk of colon cancer,
as it is a very good source of selenium, a trace mineral which
induces DNA repair and synthesis in damaged cells and
inhibits the proliferation of cancer cells. Selenium is an
antioxidant and is essential for thyroid hormone metabolism
and immune function (Anonymous, 2004) [1]. Selenium plays
an important role in cancer prevention as a cofactor of
glutathione peroxidase, which is one of the body’s most
important anti-oxidant enzyme and is used in liver to detoxify
a wide range of potentially harmful molecules (Vogt et al.,
2003) [26].
Inositol hex phosphate, a naturally occurring molecule found
in high-fibre foods such as brown rice, isa compound that has
shown to demonstrate cancer prevention properties. Inositol
hex phosphate holds great promise in strategies for the
prevention and treatment of cancer (Anonymous, 1998) [3].
Evidence suggests that dietary rice bran may exert beneficial
effects against breast, lung, liver, and colorectal cancer
(Henderson et al., 2012) [10]. The potential chemopreventive
agents in the bran are ferulic acid, tricin, β-sitosterol, γ-
oryzanol, tocotrienols/ tocopherols, and phytic acid (Barnes et
al., 1991) [5]. The anticancer effects of the rice bran are
mediated through the ability of these agents to induce
apoptosis, inhibit cell proliferation, and alter cell cycle
progression in malignant cells. These protect against tissue
damage through the scavenging of free radicals and the
International Journal of Multidisciplinary Research and Development
blocking of chronic inflammatory responses. These have also
been shown to activate anticancer immune responses as well
as affecting the colonic tumour microenvironment making it
favourable for global dietary chemoprevention. Therefore, the
establishment of dietary rice bran as a practical food has
potential to have a significant impact on cancer prevention for
the global population (Kannan et al., 2008) [13].
Lignans protect against heart disease
One type of phytonutrient especially abundant in brown rice
are plant Lignans, which are converted by friendly flora in our
intestines into mammalian Lignans, including one called
enterolactonethat is thought to protect against breast and other
hormone-dependent cancers as well as heart disease (James et
al., 1999) [11].
Helps increase energy levels
Brown rice is an excellent source of manganese and
magnesium. Just one cup of brown rice will provide 88% of
the daily value for manganese. This trace mineral helps
produce energy from protein and carbohydrates and is
involved in the synthesis of essential fatty acids. Manganese is
also a critical component of a very important antioxidant
enzyme called superoxide dismutase that is found inside the
body's mitochondria where it protects against damage from
the free radicals produced during energy production (Kannan
et al., 2008) [13].
Tune down and bone up on brown rice
Magnesium, found in good amount in brown rice, has proven
to be helpful in reducingthe severity of asthma, lowering high
blood pressure, reducing the frequency of migraine headaches
and reducing the risk of heart attack and stroke. Magnesium
helps regulate nerve and muscle tone by balancing the action
of calcium. In many nerve cells, magnesium serves as nature's
own calcium channel blocker, preventing calcium from
rushing into the nerve cell and activating the nerve. By
blocking calcium's entry, magnesium keep our nerves (and the
blood vessels and muscles they enervate) relaxed. A cup of
brown rice provides 21% of the daily value for magnesium
(Jiamyangyuen and Buncha, 2008) [12].
Helps prevent atherosclerosis
Atherosclerosis is a condition where the arteries become
narrowed and hardened due to build-up of plaque around the
artery wall. The disease disrupts the flow of blood around the
body, posing the risk of serious complications. Brown rice
helps raise blood levels due to nitric oxide, a small molecule
known to improve blood vessel dilation and prevent
development of atherosclerotic plaques (Panlasiguiand
Thompson, 2006).
Weight Loss
Brown rice is concentrated source of fibre andis ideal for
losing weight as it stays in our stomach for a longer time as
compared to other foods. This allows slower digestion, thus
making us feel full for longer period of time. So instead of
consuming two bowls of white rice, eating one bowl of brown
rice helps to attain satiety. Fibre also moves fat through our
digestive system faster so that less of it is absorbed. It also
controls blood sugar level (James et al., 1999) [11].
Some researchers have indicated that whole grain including
rice bran is linked to reduced risk of obesity and weight gain.
Whole grain intake was inversely related to body mass index
(Slavin, 2005) [23].
Table 2: Selected bioactive compounds in rice bran evaluated for their properties with regard to prevention of chronic disease
Rice bran compound
Disease prevention activity
Ferulic acid
Antioxidant, chemopreventive, anti-inflammatory, and lipid-lowering effects
Antioxidant, chemopreventive, anti-inflammatory, and lipid-lowering effects
Inositol hexaphosphate
Blocks cancer growth and signaling
Blocks cholesterol
Linoleic acid
Inhibits lipid peroxidation and intracellular signaling
Inhibits lipid peroxidation and intracellular signaling
Salicylic acid
Caffeic acid
Gastrointestinal microbe interactions
Coumaric acid
Antimutagenic, inhibits the cell cycle, antioxidant, and chemopreventive
Antimutagenic, inhibits the cell cycle, antioxidant, and chemopreventive
Source: Ryan, 2011
Whole foods contain thousands of phytonutrients that have
health-promoting properties, as well as vitamins, minerals and
macronutrients like fibre and beneficial fats. Wholefoods are
easily assimilated and absorbed readily by the body. But
processing leads to reduction in many of these compounds.
The current existence of milled rice on the market reduces the
rice’s nutritional value and essentially turns it into a simple
carbohydrate food. Therefore, in addition to developing more
nutritious varieties, awareness of the benefits of eating brown
rice should be raised among rice consumers. Brown rice is a
wealth of nutrients that are contained in the bran layer. This
lost health food is now being revived and taken back into the
regular diet of consumers. Such an approach would ultimately
result in a sustainable enhancement of the essential nutrient
supply in rice-based diets.
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Formulation of gluten free crackers based on brown rice flour from two varieties and apple pomace was studied during the present investigation. Pomace flour blends were prepared by incorporating 0%, 3%, 6% and 9% apple pomace in brown rice flour. Viscosity profile showed decrease in pasting properties except pasting temperature which increased with increase in pomace level. The hunter colour value (L∗) and fracture force of crackers are decreased with increase in pomace level. The crackers were investigated and compared for composition, antioxidant properties (DPPH, total phenolic content, total flavonoid content, reducing power), minerals and sensory properties. The increased amount of apple pomace in the flour formulation resulted in higher antioxidant properties, total dietary fibre and minerals in the final product. Based on the present study, pomace based rice crackers have good potential for consumer and regarded as health promoting functional food, especially for coeliac disease patients.
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1 Abstract: Rice is a staple food for over half of the world's population. Today people are going for whole food, to the days our forefather had been eating. You hardly heard of cancer, heart attack and diabetics and so on. All these degenerative deceases in our present society are caused by the pollutants from within and without. White food, better known as refined carbohydrates was once a delicacy affordable only to the financially wealthy. However, financial wealth does not equate to a wealth of health. A primary reason for the development of refining wheat for white flour products is to establish a longer shelf life. Whole wheat flour left in sacks for long periods of time cause bugs to appear within it. In their natural form, whole grains contain natural nutrients vital to our health.
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Iron deficiency anemia is thought to affect the health of more than one billion people worldwide, with the greatest burden of disease experienced in lesser developed countries, particularly women of reproductive age and children. This greater disease burden is due to both nutritional and infectious etiologies. Individuals in lesser developed countries have diets that are much lower in iron, less access to multivitamins for young children and pregnant women, and increased rates of fertility which increase demands for iron through the life course. Infectious diseases, particularly parasitic diseases, also lead to both extracorporeal iron loss and anemia of inflammation, which decreases bioavailability of iron to host tissues. This paper will address the unique etiologies and consequences of both iron deficiency anemia and the alterations in iron absorption and distribution seen in the context of anemia of inflammation. Implications for diagnosis and treatment in this unique context will also be discussed.
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Six normolipidemic males ingested on separate days a low-fiber test meal [2.8 g dietary fiber (TDF)] containing 70 g fat and 756 mg cholesterol, enriched or not with 10 g TDF as oat bran, rice bran, or wheat fiber or 4.2 g TDF as wheat germ. Fasting and postmeal blood samples were obtained for 7 h and chylomicrons were isolated. Adding fibers to the test meal induced no change in serum glucose or insulin responses. The serum triglyceride response was lower (P less than or equal to 0.05) in the presence of oat bran, wheat fiber, or wheat germ and chylomicron triglycerides were reduced with wheat fiber. All fiber sources reduced chylomicron cholesterol. Cholesterolemia decreased postprandially for 6 h and was further lowered in the presence of oat bran. Serum apolipoprotein (apo) A-1 and apo B concentrations were not affected. Thus, dietary fibers from cereals may reduce postprandial lipemia in humans to a variable extent.
Effects of germination process and germination time on selected physico-chemical, eating and sensorial properties of germinated brown rice were studied. Germination process included soaking rice in water for 6 or 12 h before draining and leaving it to germinate for the periods of 0, 6, 12, 18 and 24 h. Results showed that effects of germination process on cooking and textural properties of cooked rice were more pronounced when rice was soaked and germinated for a longer period. During germination, α-amylase plays important roles and altered structure in rice kernels. Compared to cooked regular brown rice, panelists rated intensity of attributes in cooked germinated rice as being sweeter, softer, more swelled and cohesive. For rice soaked for 6 or 12 h, there was significant positive correlation between germinating time and α-amylase activity (r = 0.859 and 0.807), size expansion, gel consistency (r = 0.889, r = 0.956) and alkaline spreading value (r = 0.850, r = 0.992). On the other hand, hardness (r = -0.952, r = -0.834), amylose content (r = -0.989, r = -0.990), bulk density (r = - 0.882, r = - 0942), pasting properties, cooking time (r = -0.802, r = -0.788), % water uptake (r = -0.981, r = -0.959) and % volume expansion (r = -0.954, r = -0.964) showed significant negative correlation with germinating time.
Pre-germinated brown rice (PGBR) having the germ length of 0.5–1.0 mm is produced as a healthy food by immersing the brown rice in water. In this article, various additives were used for making PGBR breads, and suitable combinations of PGBR and additives for breadmaking were evaluated to provide PGBR bread with high functional properties. The 30% of the wheat flour was substituted with PGBR (PGBR 30), and combined additions of phytase (PHY), hemicellulase (HEM) and sucrose fatty acid ester (SE) to PGBR 30 improved the bread qualities with more suitable dough properties, as compared with the sample without their addition. During fermentation, the amounts of gas leaked from the PGBR 30 dough were suppressed by the additions. PHY and HEM hydrolyzed the phytate and hemicellulose in PGBR, and the maturity and extensibility of the PGBR 30 dough were caused by the activated yeast with formed phosphate and decomposed bran, making the large loaf volume and softness of breadcrumbs during storage. In addition, SE accelerated the dough tolerance to mixing or fermentation with the emulsifying ability. Therefore, the combined additions with PHY, HEM, and SE to PGBR 30 improved the dough and bread qualities.
Rice bran, an economical, underutilized coproduct of rough rice milling, was used to produce peptide hydrolysates, which were investigated for anticancer activity. Protein hydrolysates prepared by Alcalase hydrolysis under optimized conditions were treated further to obtain gastrointestinal (GI)-resistant peptide hydrolysates. They were fractionated into >50, 10-50, 5-10, and <5 kDa sizes and evaluated for inhibitory activity on proliferation of human colon (Caco-2) and liver (HepG2) cancer cell lines by Trypan blue dye exclusion assay. GI-resistant <5 and 5-10 kDa sized peptide fractions inhibited growth of Caco-2 cells by 80%, and the <5 kDa fraction inhibited growth of HepG2 cells by approximately 50% compared to controls and nonresistant fractions. An MTS cell titer assay confirmed antiproliferative effects of the peptide fractions. The results demonstrated that 5-10 and <5 kDa sized GI-resistant fractions promoted significant (p < 0.05) inhibitory activities on both cancer cell lines compared to controls. More investigations are needed to show such value-added effects on the technofunctional and sensorial properties of the food protein and peptide matrices.
Epidemiological studies find that whole-grain intake is protective against cancer, CVD, diabetes, and obesity. Despite recommendations to consume three servings of whole grains daily, usual intake in Western countries is only about one serving/d. Whole grains are rich in nutrients and phytochemicals with known health benefits. Whole grains have high concentrations of dietary fibre, resistant starch, and oligosaccharides. Whole grains are rich in antioxidants including trace minerals and phenolic compounds and these compounds have been linked to disease prevention. Other protective compounds in whole grains include phytate, phyto-oestrogens such as lignan, plant stanols and sterols, and vitamins and minerals. Published whole-grain feeding studies report improvements in biomarkers with whole-grain consumption, such as weight loss, blood-lipid improvement, and antioxidant protection. Although it is difficult to separate the protective properties of whole grains from dietary fibre and other components, the disease protection seen from whole grains in prospective epidemiological studies far exceeds the protection from isolated nutrients and phytochemicals in whole grains.
Our laboratory has previously reported that the hypolipidemic effect of rice bran oil (RBO) is not entirely explained by its fatty acid composition. Although RBO has up to three times more serum cholesterol-raising saturated fatty acids (SATS) than some unsaturated vegetable oils, we hypothesized that its greater content of the unsaponifiables would compensate for its high SATS and yield comparable cholesterol-lowering properties to other vegetable oils with less SATS. To study the comparative effects of different unsaturated vegetable oils on serum lipoprotein levels, nine cynomologus monkeys (Macaca fascicularis) were fed diets, for four weeks, in a Latin square design, containing rice bran, canola or corn oils (as 20% of energy) in a basal mixture of other fats to yield a final dietary fat concentration of 30% of energy. All animals were fed a baseline diet containing 36% of energy as fat with 15% SATS, 15% monounsaturated fatty acids (MONOS) and 6% polyunsaturated fatty acids (POLYS). Despite the lower SATS and higher MONOS content of canola oil and the higher POLYS content of corn oil, RBO produced similar reductions in serum total cholesterol (TC) (-25%) and low density lipoprotein cholesterol (LDL-C) (-30%). In addition, as compared to the baseline diet, the reduction in serum TC and LDL-C cholesterol with RBO was not accompanied by reductions in high density lipoprotein cholesterol (HDL-C) which occurred with the other two dietary oils. Using predictive equations developed from data gathered from several studies with non-human primates, we noted that the observed serum TC and LDL-C lowering capabilities of the RBO diet were in excess of those predicted based on the fatty acid composition of RBO. These studies suggest that non-fatty acid components (unsaponifiables) of RBO can contribute significantly to its cholesterol-lowering capability.