Monday, August 19, 2013

Barley and its health benefits

Barley - Hordeum vulgare

Barley is a high protein, high fibre whole grain with numerous health benefits. It contains gluten, though not as much as wheat, so is unsuitable for those on a gluten-free diet.

When cooked, barley has a pleasant chewy texture and nutty flavour.

Traditionally, it is used in soups and stews but you can use it like any other grain such as rice. It is, for example, a good alternative to arborio rice for use in risottos and can be used in salads, stir-fries or to make porridge.

Read on to find out more about barley, its health benefits and how to cook it.



Barley, wheat and rye are all related members of the same botanical family (Triticeae) and thus share many genetic and biochemical characteristics.

In contrast to wheat, cultivated barley comprises only one species, Hordeum vulgare.

Barley grain ranks fourth in cereal production, with a world output of 130 million tonnes in 2012 (FAOSTAT).

The crop requires a temperate climate; the principal growing areas are Europe and the Russian Federation but it is also a valuable and resilient crop in arid and semi-arid areas of Asia, the Middle East and North Africa.


Field of barley
Source: Wikimedia Commons

Barley is one of the most ancient cultivated grains in the world.

It originated in Ethiopia and Southeast Asia, where it has been cultivated since 8000 BCE. More varieties of barley are found today in Ethiopia than in any other area of comparable size.

The ancient Greeks relied on barley to make bread and athletes attributed their physical strength to their barley containing diets.

Roman Gladiators were called Hordearii, or Barley Men. It's said they believed barley gave them greater strength and stamina than other foods.

In Ancient China, barley was considered a symbol of male virility due to the numerous seeds in a single head of barley.

Ancient Chinese medical practitioners considered that barley strengthens the spleen-pancreas, regulates the stomach, and fortifies the intestines; builds the blood and yin fluids and moistens dryness; promotes diuresis; benefits the gall bladder and nerves; and is very easily digested.

They used it to feed convalescents and invalids; treat diarrhoea; soothe inflamed membranes; alleviate painful and difficult urination; quell fever; and to reduce tumours, swellings and watery accumulations such as oedema.



More than 80 per cent of the barley crop is used for animal feed and as malt in alcoholic beverages, such as beer and whisky.

Beer is an ancient beverage. Clay tablets describing the beer brewing process and dating back more than 5,000 years have been found in Mesopotamia.

Impression of a Sumerian cylinder seal from the Early Dynastic IIIa period (ca. 2600 BC; see Woolley 1934, pl. 200, no. 102 [BM 121545]). Persons drinking beer are depicted in the upper row. The habit of drinking beer together from a large vessel using long stalks went out of fashion after the decline of Sumerian culture in the 2nd millennium BC.


According to these tablets, Sumerians used to prepare “beer bread” out of germinated barley seeds. By crumbling this bread into water, they obtained a liquid called “sikaru”, which was finally boiled and mixed with a few herbs, resulting in a drink free of harmful bacteria.

Sprouted barley is high in maltose and is also used to make malt syrup.





Types of barley grain products


You may be confused about all the different types of barley products available, so here is a short guide:

1.  Covered barley


Covered barley, is barley in its original form in the field. It usually has a tough, inedible outer hull around the barley kernel. This covering must be removed before the barley can be eaten.


Barley grain in the field - www.freefoto.com

2.  Hulless or naked barley


Hulless or naked barley is a less common variety that has a covering, or hull, that is so loose that it usually falls off during harvesting. This cuts down on processing and ensures that all of the bran and germ are retained.


Hulless or naked barley - www.sprouting.com

3.  Hulled, de-hulled or pot barley


Hulled barley, sometimes referred to as de-hulled or pot barley, is covered barley that has been minimally processed to remove only the tough inedible outer hull. It is difficult to remove the hull carefully so that some of the bran is not lost – but that's what must be done for covered barley to be considered whole grain.

De-hulled, hulled or pot barley - www.cookingforhealth.biz


4.  Barley grits


Barley grits. When barley kernels are cut into several pieces, they become grits. Read the label carefully: grits from hulled or hulless barley are whole grain, but grits created by cutting up pearl barley are not considered whole grain.

Barley grits - www.forthegourmet.com

5.  Barley flakes


Barley flakes look similar to oat flakes and are produced the same way - by steaming kernels, rolling them, and drying them. As with barley grits, flakes can be made from whole grain barley or from pearl barley, with only the former considered to be whole grains. Barley flakes cook faster, because they've been lightly steamed and because of their greater surface area.


Barley flakes - www.oatmillers.com

6.  Barley flour


Barley flour is used in baked goods and as a thickener for soups, stews and gravies. While it contains gluten, the protein that helps baked goods rise, the type of gluten in barley flour does not promote adequate rising on its own, so barley flour is usually used with wheat flour. Look for whole grain barley flour, ground from hulled or hulless barley, not from pearl barley.


Barley flour - www.artisanfoodexpress.com

7.  Pearl barley


Pearl barley is not a whole grain. It has been polished, or "pearled" to remove some or all of the outer bran layer along with the hull. If it's lightly pearled, pearl barley will be tan coloured; if it's heavily pearled, barley will be almost white. Most of the barley found in the typical supermarket is pearl barley. Although it is technically a refined grain, it's much healthier than other refined grains because (a) some of the bran may still be present and (b) the fibre in barley is distributed throughout the kernel, and not just in the outer bran layer. Pearl barley cooks more quickly than whole grain barley.


Pearl barley - www.organic.4max.us

8.  Quick pearl barley


Quick pearl barley is a type of barley flake that cooks in about 10 minutes, because it has been partially cooked and dried during the flake-rolling process. Although barley flakes can be whole grain and technically it would feasible to create quick whole grain barley (similar to quick oats, which are whole grain), the quick barley commercially available today is made from pearl barley and so is not whole grain.

Quick pearl barley flakes - www. goldencrops.com.tw

Nutrition highlights


Fibre


Barley is highest in fibre of all the whole grains, with common varieties averaging about 17 per cent fibre, and some having up to 30 per cent fibre.  For comparison, brown rice contains 3.5 per cent fibre, corn about 7 per cent, oats 10 per cent and wheat about 12 per cent.

While the fibre in most grains is concentrated largely in the outer bran layer, barley's fibre is found throughout the whole grain, which may account for its extraordinarily high levels.

Like oats, the fibre in barley is rich in beta-glucans, which have been shown to lower cholesterol by various mechanisms.

Starch


Starch is the major component in barley kernels amounting 60 - 70 per cent of the dry matter. Starch itself is composed of two types of glucose polymers namely the highly branched amylopectin and the linear amylose.

Protein


Barley has more protein than corn, brown rice, millet, sorghum or rye, with levels ranging from 7 to 25 per cent depending on the variety and growing conditions.

When compared with the World Health Organisation (WHO) requirements for essential amino acids for humans, wheat, barley and rye contain all of them but are seen to be deficient in lysine, with threonine being the second limiting amino acid.

The content of amino acids in a typical barley variety in relation to WHO recommendations is shown below.

Some varieties, such as Prowashonupana (Conagra) have been bred for high lysine content (>4 g/100g protein).



Other plant foods contain substantial quantities of lysine, however, so provided you eat a varied diet, this is nothing to worry about.

A list of plants high in lysine is shown below:


Vitamins and minerals


Barley is an excellent source of the minerals selenium and manganese and a good source of copper, magnesium and phosphorus; it contains four times more magnesium than calcium.

Selenium is a trace mineral. Although we only need small amounts, it is essential for helping to prevent cellular damage from free radicals, to regulate thryoid function, and for a healthy immune system.

Manganese helps us handle oxidative stress. It activates many important enzymes in the body that are crucial to metabolism of carbohydrates, amino acids, and cholesterol. Manganese is also essential to the formation of healthy cartilage and bone.

Magnesium is an essential mineral required for hundreds of biochemical reactions, including transmission of nerve impulses, converting food into energy, body temperature regulation and maintaining a strong immune system. Magnesium also helps us absorb calcium, for healthy bones and teeth.

Another essential mineral, phosphorus is present in every cell in your body, making up 1 per cent of your body weight. Its main function is the formation of bones and teeth, but it is also key to the synthesis of protein for cell repair, growth, and maintenance; for heartbeat regularity; and nerve conduction.

Unlike corn, barley is a good source of niacin (vitamin B3) and thiamine (vitamin B1).

B vitamins help with metabolism, the process your body uses to make energy from the food you eat. While each has its own functions, in general they also help maintain healthy skin, hair and muscles; form red blood cells; and promote healthy immune and nervous system function. Some research shows that B vitamins also prevent mood swings.




Phytonutrients


Barley is rich in phytochemicals with antioxidant activity. These phytochemicals are thought to be responsible for many of barley's health benefits.

The barley variety Prowashonupana has an antioxidant capacity of 4600 umol per g. This compares with values of 6220 umol per g for cultivated blueberries; 3557 umol per g for strawberries, 3037 umol per g for raisins; and 2640 umol per g for spinach.

Barley grains contain a wide range of phenolic acids, anthocyanins, carotenoids and tocopherols which have powerful antioxidant activity.

Lutein and zeaxanthin are the two main carotenoids identified in barley.

Vitamin E or tocopherols are also present in substantial concentrations.

Health benefits


Type 2 diabetes, insulin and glucose response


Diets high in whole grains are associated with a 20-30 per cent reduction in risk of developing type-2 diabetes, which is attributed to a variety of wholegrain components, notably dietary fibre, vitamins, minerals and phytochemicals. Most phytochemicals function as antioxidants in vitro and have the potential to mitigate oxidative stress and inflammation which are implicated in the pathogenesis of type 2 diabetes.

There is evidence that barley is more effective than oats at helping blood sugar regulation.

REFINED VS WHOLE GRAINS AND TYPE 2 DIABETES
Scientists at Columbia University and Stanford collaborated to reflect on the association between rapidly rising rates of type 2 diabetes and cardiovascular disease in India, and the adoption of refined carbohydrates – especially white rice and white flour – in that country. They advocated re-introduction of whole grains commonly consumed before 1950, including amaranth, barley, brown rice, millet, and sorghum, as a way to stem chronic disease in culturally-sensitive ways.

GLYCAEMIC RESPONSE
Fibre is one of the factors that is known to slow the uptake of glucose into the blood stream after eating. Researchers at Oxford Brookes University in the UK set out to explore whether whole grain barley with different fibre levels (10% fibre vs 16% fibre) or in different serving sizes (25g and 50g of available carbohydrate) would affect glycaemic response. They found no difference in any of the variables, but all of the barley porridge options elicited a significantly low glycaemic response.

Dutch researchers used a crossover study with 10 healthy men to compare the effects of cooked barley kernels and refined wheat bread on blood sugar control. The men ate one or the other of these grains at dinner, then were given a high glycaemic index breakfast (50g of glucose) the next morning for breakfast. When they had eaten the barley dinner, the men had 30 per cent better insulin sensitivity the next morning after breakfast.

RICE VS BARLEY
White rice, the staple food in Japan, is a high glycaemic index food. Researchers at the University of Tokushima found that glucose levels were lower after meals when subjects switched from white rice to barley.

BARLEY BETA+GLUCAN LOWERS GLYCAEMIC INDEX
Scientists at the Functional Food Centre at Oxford Brookes University in England fed 8 healthy human subjects chapatis (unleavened Indian flatbreads) made with either 0g, 2g, 4g, 6g or 8g of barley beta-glucan fiber. They found that all amounts of barley beta-glucan lowered the glycemic index of the breads, with 4g or more making a significant difference.

In a crossover study involving 17 obese women at increased risk for insulin resistance, USDA scientists studied the effects of 5 different breakfast cereal test meals on subjects’ insulin response. They found that consumption of 10g of barley beta-glucan significantly reduced insulin response.

Swedish researchers at Lund University have determined that certain whole grain products can help control blood sugar for up to ten hours. A team led by Anne Nilsson fed twelve healthy subjects test meals including different whole and refined grains, and found that barley and rye kernels at one meal had a long-lasting effect on controlling blood sugar extending to most of the day after the whole grain breakfast, or overnight with whole grains at dinner.

BARLEY VS OATS
USDA researchers fed barley flakes, barley flour, rolled oats, oat flour, and glucose to 10 overweight middle-aged women, then studied their bodies’ responses. They found that peak glucose and insulin levels after barley were significantly lower than those after glucose or oats. Particle size did not appear to be a factor, as both flour and flakes had similar effects.

Blood pressure


For five weeks, adults with mildly high cholesterol were fed diets supplemented with one of three whole grain choices: whole wheat/brown rice, barley, or whole wheat/brown rice/barley. All three whole grain combinations reduced blood pressure, leading USDA researchers to conclude that "in a healthful diet, increasing whole grain foods, whether high in soluble or insoluble fibre, can reduce blood pressure and may help to control weight."

Cholesterol and serum lipids


University of Connecticut researchers reviewed 8 studies evaluating the lipid-reducing effects of barley. They found that eating barley significantly lowered total cholesterol, LDL (“bad”) cholesterol, and triglycerides, but did not appear significantly to alter HDL (“good”) cholesterol.

A randomized double-blind study in Japan followed 44 men with high cholesterol for twelve weeks, as the men ate either a standard white-rice diet or one with a mixture of rice and high-beta-glucan pearl barley. Barley intake significantly reduced serum cholesterol and visceral fat, both accepted markers of cardiovascular risk.

25 adults with mildly high cholesterol were fed whole grain foods containing 0g, 3g or 6g of barley beta-glucan per day for five weeks, with blood samples taken twice weekly. Total cholesterol and LDL (“bad”) cholesterol significantly decreased with the addition of barley to the diet.

University of California researchers fed two test meals to 11 healthy men, both containing beta-glucan. One meal was a high-fibre (15.7g) barley pasta and the other was  lower-fibre (5.0g) wheat pasta. The barley pasta blunted insulin response, and four hours after the meal, barley-eaters had significantly lower cholesterol concentration than wheat-eaters.


Roman gladiators were known as hordearii or barley men - their diet was based on barley and beans, which gave them strength and stamina to fight in public arenas

Cardiovascular disease


Penny Kris-Etherton and Kristin Harris at Penn State's Department of Nutrition Sciences, reviewed research on whole grains and coronary heart disease risk in an effort to explain mixed results from one study to another. They concluded that, "due to the varying nutrition compositions of different whole grains, each could potentially affect coronary heart disease risk via different mechanisms."

Whole grains high in soluble fibre tend to decrease LDL cholesterol and improve insulin response, for example, while those high in insoluble fibre may have a prebiotic effect, while lowering glucose and blood pressure.

While intervention studies have not proven the observed epidemiological link between whole grains and weight loss, visceral fat loss has been shown. Differences in processing of whole grains may also affect their heart-healthy potential.

Eating an average of 2.5 servings of whole grain foods each day can lower your risk of cardiovascular disease by almost one-quarter. That's the finding of a seven-study meta-analysis of 285,000 men and women led by Philip Mellen of Wake Forest University. In light of this evidence, Mellen said, policy-makers, scientists and clinicians should "redouble efforts" to get people to eat more whole grains.

Another study by Philip Mellen at Wake Forest University and colleagues measured atherosclerosis of the common carotid artery, and its progression over five years. Mellen's team found that, among the 1178 men and women in the study, those who ate more whole grains had less unhealthy artherosclerotic thickening of the common carotid artery.

After following 21,376 male physicians for almost 20 years, Luc Djoussé and J. Michael Gaziano at Harvard found that those eating two to six servings of whole grain cereal a week reduced their risk of heart failure 22%, while those eating whole grains daily reduced risk by 28%. For this study, cereals with at least 25% whole grain or bran by weight were classified as whole grain.

Researchers led by Dr. Mark Pereira collected data on 91,058 men and 245,186 women who participated in 10 studies in the US and Europe. After 6-10 years of followup, the research showed that, for each 10 grams of fibre consumed per day, there was a 14% reduction in heart disease risk and a 25% reduction in risk of dying from heart disease. In short, the cereal fibre in whole grains appears to make heart disease much less likely—and less serious if it does occur.


Cancer


Researchers at Imperial College London conducted a meta-analysis of 25 studies involving almost two million people (and 14,500 cases of colorectal cancer) to assess the links between colorectal cancer and both whole grains and total dietary fibre. They concluded that there is a credible "dose-response" relationship between whole grain consumption and reduced cancer risk; they estimate that eating three or more servings of whole grains per day lowers colorectal cancer risk nearly 20 per cent. Dietary fibre also reduces this risk, but cereal/grain fibre shows stronger benefits than other types of fibre.

Researchers in Brazil conducted a meta-analysis of 11 cohort studies including 1,719,590 participants, who were followed from 6 to 16 years. Their overall conclusion was that "consumption of whole grains was inversely associated with the risk of developing colorectal cancer."

Reduced colonic transit time has been implicated in reducing the incidence of colon cancer, as evidenced by populations consuming diets rich in fibre.

The high fibre content of barley makes it one of the most effective grains for reducing colon transit time. Its high antioxidant content also reduces oxidative stress in the gut, reducing the risk of damage to the gastro-intestinal tract which can lead to cancer.

Increasing attention is being paid to overall dietary patterns and their relationship to health, rather than single nutrients or foods. In one such study of more than 50,000 African-American women, researchers found that eating a "prudent diet" (high in fruits, vegetables, fish and whole grains) rather than a "Western diet" (more refined grains, processed meats, sweets) cut the risk of breast cancer. The findings were especially strong for thinner, younger women and for certain types of breast cancer.

Pancreatic cancer is the most fatal cancer in the U.S., but eating two servings or more of whole grains daily may cut the risk of this swift and deadly killer by up to 40 per cent. That was the finding of researchers at UC San Francisco led by June Chan, who compared diets of 532 pancreatic cancer patients with 1,701 people not suffering from the disease.

Barley is rich in beta-glucans which are known to boost the immune system and have anti-cancer properties.

Extracts of barley were shown to prevent proliferation of Caco-2 colon cancer cells in a dose-dependent manner (p<0 .05="" p="">
Protocatechualdehyde (PCA) is a naturally occurring polyphenol found in barley, green cavendish bananas, and grapevine leaves.

Although a few studies reported growth-inhibitory activity of PCA in breast and leukaemia cancer cells, the underlying mechanisms are still poorly understood.

Researchers at the University of Maryland in the USA performed an in vitro study and found that this barley phytochemical suppressed cell growth and induced apoptosis in human colorectal cancer cells in a dose-dependent manner.



Eye health


Barley contains appreciable quantities of the carotenoids lutein and zeaxanthin.

Lutein and zeaxanthin are responsible for the coloration of the macula lutea (‘yellow spot’) of the retina, the area of maximal visual acuity.

Dietary lutein and zeaxanthin are known protect against age-related macular degeneration and cataract.

It is therefore possible that consumption of barley can protect the health of the eyes, though further studies are required to provide direct evidence for this.

Furthermore, lutein and zeaxanthin possibly act together with other bioactive compounds against cancer, cardiovascular risk and other diseases.

Depression and mood disturbances


Talbinah or talbina is a barley syrup cooked with milk and sweetened by honey. In his famous Hadith on Talbinah, the Prophet Mohammad (SAW) recommended it for soothing hearts and relieving sadness.




Researchers in Malaysia conducted a 3-week crossover designed, randomized clinical trial to determine the effect of Talbinah on mood and depression among institutionalized elderly people in Seremban. They found a statistically significant decrease in depression, stress, and mood disturbances scores among the group given talbinah (P greater than 0.05) compared with the controls.

Conclusion


Current scientific evidence indicates that whole grains, including barley, play an important role in lowering the risk of chronic diseases, such as coronary heart disease, diabetes, and cancer, and also contribute to body weight management and gastrointestinal health.

Rather than becoming fixated on individual foods and nutrients, it is important to understand the big picture - that a diet high in whole grains, vegetables, beans, pulses, nuts, seeds and fruit is optimum for human health in the long term.

How to cook barley


Cereals need to be thoroughly cooked and chewed in order to be properly digested.  Although fashionable, the habit of lightly cooking grains to keep them dry and separate can be a recipe for intestinal discomfort and poor nutrient absorption.




For best results, cook grains as follows:

  • Wash thoroughly, preferably changing the water 2-3 times until the remaining water is clear
  • Remove all husks and any debris arising in the cooking water
  • Measure the grain and the appropriate amount of water accurately. 
For barley, the ratio is one cup barley grain to three cups water. It is best to soak barley for a few hours before cooking.
  • Place the lid on the pan firmly. The lid should have no holes in it.
  • Bring to a boil, then turn down heat as low as possible and simmer on a very low flame using a flame deflector for the required time.  Check cooking time carefully. 
For minimally processed barley, like pot barley, it will need to be boiled for 50-60 minutes.
Pearl barley may take less time.
  • When ready, remove from the cooker and leave to stand uncovered for about 5 minutes before transferring to a serving dish.


Check out my next post for a recipe for a satisfying and delicious barley, mushroom, butternut squash and ginger risotto.








If you have enjoyed this post, please sign up for my newsletter to keep informed of new information, recipes and courses and visit my website.

You can also join me on Facebook, PinterestTwitter and LinkedIn.






No comments:

Post a Comment