Rosemary K. Newman

A Brief History of Barley Foods

Barley is one of the oldest cultivated cereal grains and currently ranks fourth (7,21) or fifth (15) in acreage and crop production worldwide. In the United States, the current use of barley as food ranks a distant third (1.5%) behind use as animal feed (65%) and in malt and alcohol production (30%). In 1991, barley used as food in the European Union (12 countries) was even lower (0.3%) than in the United States. In contrast, during the same time period food was the largest use for barley in Morocco (61%), China (62%), India (73%), and Ethiopia (79%) (15). A small portion of barley malt is used in food products principally to enhance flavor; however, the major use of barley malt is in the production of alcoholic beverages. Although alcoholic beverages are not foods in the strictest sense, they do contribute some nutrition, either with or apart from meals, to the diet. Considerable evidence is available that points to the role of barley as a sustaining food source in the evolution of humans. Indeed, it was one of the most important food grains in the ancient world. Additionally, alcoholic beverages of various types and fermented foods prepared from barley are commonly referred to in the ancient literature. As other food grains (e.g., wheat, rye, and oats) became more abundant, barley was relegated to the status of “poor man’s bread” (31). However, current consumer interest in nutrition and health may help restore barley’s status in the human diet. This article provides some historical perspectives on the origin, domestication, and food uses of barley. Our knowledge of barley’s prehistory comes from archaeological studies of ancient civilizations. It is generally accepted as fact that the transformation of wild barley into a cultivated crop (domestication) occurred over many millennia (31). Fragile ears, a characteristic of wild barley, made it difficult to harvest seeds at maturity. It has been postulated that natural mutations in wild barley produced plants with less fragile ears that had larger, more abundant seeds that were naturally preferred and selected for food by huntergatherers. One may logically conjecture that agriculture began when seeds from these plants were planted, either accidentally or intentionally, producing a “barley crop.” The first barley foods probably were quite simple. The kernels were eaten raw until the discovery that removal of the hulls of hulled types followed by soaking and/or cooking in some manner enhanced the texture and flavor. It is also logical to conclude that this may have been when early humans learned about fermentation and how to produce alcoholic beverages.

Barley β‐glucan is effective as a hypocholesterolaemic ingredient in foods

Barley contains high levels of soluble dietary fibre, including mixed linked 1→3, 1→4β-D-glucans (β-glucan). An extract of β-glucan from waxy, hulless barley containing 56% total dietary fibre (TDF) was incorporated into flour tortillas, cornstarch pudding and apple granola bars to provide 2 g soluble fibre as β-glucan per serving. The foods were tested for objective functional properties. Flour tortillas with β-glucan were incorporated into rat diets and compared to diets containing an equivalent amount of cellulose, to test the fibre effect on growth and lipid metabolism parameters. Rats fed β-glucan tortillas had lower feed consumption and body weight (P 0·05). Plasma LDL-cholesterol of rats fed β-glucan was lower (P 0·05). Rats fed β-glucan tortillas had higher (P<0·05) faecal fat excretion, suggesting impairment of intestinal fat absorption. Liver composition data showed lower (P<0·05) levels of total lipid and cholesterol in β-glucan-fed rats. The results suggest that the barley β-glucan concentrate has potential as a food ingredient to provide supplemental soluble fibre which may be beneficial in reducing plasma LDL-cholesterol in humans.

A Stage-of-Change Classification System Based on Actions and Beliefs Regarding Dietary Fat and Fiber

Purpose. The objectives of this study were to develop a stage-of-change classification system and to determine the degree to which various adult subgroups have adopted the behavioral changes necessary to achieve a low-fat and/or high-fiber diet as recommended by the Dietary Guidelines for Americans. Design. The study used a mail survey randomly sent to 7110 adults. Setting. The survey was conducted in 11 states and the District of Columbia. Subjects. The random sample included males and females over age 18. Of the eligible respondents, 3198 (51.5%) were included in this analysis, with 2004 and 2066 unambiguously classified into stages of change for fat and fiber, respectively. Measures. Stage of change was defined by an algorithm based on self-reported intent and behaviors to limit fat and/or increase fiber. Results. 45% of the respondents were classified as being in action/maintenance for fat and 38% for fiber. Women, older adults, individuals with advanced education, persons with diet-related chronic disease, people with higher levels of relevant nutrition knowledge and attitudes, and persons who indicated that health concerns were a primary influence on their diet were more likely to be in action/maintenance than other respondents. Conclusions. The algorithm in this study presents a model that more closely reflects the proportions of the adult population that have achieved low-fat diets and classifies a greater proportion in the preparation stage than classification systems in previous studies.

Tocotrienol and fatty acid composition of barley oil and their effects on lipid metabolism.

Barley oil was extracted with hexane from the grain of a high oil waxy hull-les barley. Twelve male broiler chicks were fed corn-based diets with either 10% barley oil, 10% corn oil or 10% margarinead libitum for ten days. Total plasma cholesterol concentration of the chicks fed barley oil was 34% lower (p<0.05) than that of the chicks fed margarine. Plasma low density lipoprotein cholesterol concentration of chicks fed barley oil was 53% and 59% lower (p<0.05) than those of chicks fed corn oil and margarine, respectively. Plasma high density lipoprotein cholesterol and triglyceride concentration of the barley oil group were similar to those of the margarine but higher (p<0.05) than those of the corn oil group. Chicks fed the barley oil gained more (p<0.05) body weight than those fed the corn oil and margarine. Barley oil had an effect in suppression of TC and LDLC in chicks compared to margarine. Barley oil supressed LDLC but not HDLC in chicks compared to corn oil. A greater weight gain of the chicks fed barley oil suggested that these chicks had normally functioning digestion and absorption. α-Tocotrienol and γ-tocotrienol content of the barley oil were 24 and 17 times greater, respectively, than those observed in the corn oil, while the same fractions were not detectable in the margarine. Polyunsaturated fatty acid content of the barley oil was more than threefold that of margarine. These data suggest that α-tocotrienol and polyunsaturated fatty acids are hypocholesterolemic components in barley oil.

COMPARATIVE CHOLESTEROL-LOWERING EFFECTS OF BARLEY β-GLUCAN AND BARLEY OIL IN GOLDEN SYRIAN HAMSTERS

The cholesterol-lowering effect of barley and more specifically the contribution of barley fiber and barley oil to cholesterol-lowering was studied in hamsters. This was achieved by comparing a semi-purified diet containing cellulose and peanut oil (control) to a whole barley diet and barley diets from which barley fiber, barley oil, or barley oil and barley fiber were removed. The barley fiber was removed enzymatically and the oil was extracted with hexane. The cholesterol-lowering effect of the barley oil was also tested by adding it in place of peanut oil to the control semi-purified diet. Plasma triglycerides and HDL cholesterol levels were not influenced by dietary treatments. Total plasma cholesterol was lower (P < 0.05) in hamsters fed diets containing barley soluble dietary fiber compared to those fed barley diets with SDF removed or those fed insoluble dietary fiber. Barley oil had no statistically significant lowering effect on plasma cholesterol levels compared to those of the controls. The data presented in this study with the hamster model supports the cholesterol-lowering effect of soluble fiber previously reported in other species, but does not support all reports concerning oils and nonsaponifiable oil constituents in this respect. Copyright

Effect of full-fat or defatted rice bran on serum cholesterol

Rice bran has been shown to lower serum cholesterol in hamsters. Leghorn cockerel chicks were fed 60% full-fat rice bran (FFRB) and corn/soy (CS) diets with 0.5% added cholesterol. Both diets contained 19% protein. All reported parameters are on blood serum. Significant differences (p<0.05) were found in total cholesterol (TC), triglycerides (TG), high-density and low-density lipoprotein cholesterol (HDL and LDL). In a second study, chicks were fed FFRB, defatted rice bran (DFRB), and CS diets balanced for 18% protein, 14.47% total dietary fiber and 10.78% lipid with 0.5% added cholesterol. Both TC and TG were significantly lower (p<0.05) in chicks fed FFRB and CS diets. Significant differences were found in HDL values for all diets with FFRB exhibiting the highest mean value (155 mg/dl) and CS exhibiting the lowest mean value (114 mg/dl). All diets were significantly different (p<0.05) in LDL, with mean values of 249, 318 and 275 mg/dl for FFRB, DFRB and CS, respectively. FFRB appears to increase HDL and to lower LDL in chicks, but does not always affect TC, whereas DFRB may increase all three serum lipid components.

Dietary selection for lysine by the chick

Broiler chicks were provided choices of synthetic diets (a) adequate or low in lysine, and (b) adequate in or devoid of lysine. In each case, chicks consumed some of each diet offered, but preference was shown for the adequate lysine diet. Growth rates of chicks given choices ranged from 80% of that of chicks fed an adequate lysine diet with no choice for two weeks, then growth rates fell to about 60% of those fed adequate lysine. In another study, chicks were fed a diet devoid of lysine but were offered pure L-lysine HCl in a separate feeder. These chicks selected some of the supplementary lysine, but their body weights were only 68% of the body weight of chicks fed an adequate lysine diet after 21 days. Chicks given a choice of diets prepared with an adequate quantity of either L- or D-lysine preferred with L-lysine diet but did not select sufficient quantity to reach normal growth. These observations indicate that chicks can discern the presence of L-lysine in diets or separately, but will not select sufficient quantity for maximum growth potential. A diet prepared with D-lysine was more acceptable than one completely devoid of lysine, suggesting some sensory recognition for lysine.

Oat β-glucan-amylodextrins: Preliminary preparations and biological properties

Amylodextrins with soluble β-glucan contents from 1 to 10% were prepared from oats and the hypocholesterolemic properties of the latter were evaluated. The products are called OATRIM and can lower blood cholesterol by replacing animal fats rich in cholesterol in food products and, possibly, by the action of β-glucan in the body after consumption. In the chick model, decreased total blood cholesterol also resulted in increases of HDL cholesterol and decreases of LDL cholesterol. Processing conditions were found that gave the maximum amount of β-glucan and desirable fat-replacement qualities with the least amount of color and flavor.

Reported Adoption of Dietary Fat and Finer Recommendations Among Consumers

OBJECTIVE To identify constraints in adopting dietary fat and fiber recommendations. DESIGN A questionnaire was mailed to a sample of the general population, a convenience sample of persons with heart disease and cancer in 11 states, and registered dietitians in 5 states. The survey included questions on demographic and attitudinal factors that were correlated with specific practices to reduce fat intake and increase fiber intake. SETTING From the general population sample of 6,206 eligible respondents (return rate of 51.5%), those selected were respondents who indicated that they would adopt a dietary recommendation if it were good for them (n = 2,682). Subsamples from the general population were matched to 362 registered dietitians and 147 persons with cancer or heart disease on selected demographic variables. Factors associated with adoption of specific behaviors were identified. STATISTICAL ANALYSIS PERFORMED Statistical analysis included chi 2, factor analysis, and analysis of variance. RESULTS The majority of persons who said they would adopt a fat-reducing behavior if it were good for their health reported practicing that behavior often or usually. More than 60% reported consuming whole grains; however, only 15% reported eating fruits and vegetables frequently. Among the general population sample, those more likely to practice a behavior had the following characteristics: female, college educated, older than 60 years, white, higher income, no children younger than 18 years, perceived health status as excellent, and absence of chronic disease. Registered dietitians and those with chronic disease were also more likely to follow dietary fat and fiber recommendations. APPLICATIONS Nutrition education messages that lead to increased consumption of dietary fiber need to be developed. Nutrition educators should provide strategies for consumers for increasing use of fruits and vegetables in all meals. Good taste and convenience are critical components. The food industry may assist by providing a wider array of convenience entrees or side dishes that feature produce and whole grains.

Growth and lipid metabolism as affected by feeding of hull-less barleys with and without supplemental β-glucanase

Three hull-less barleys, Washonupana (WSNP), Waxbar (WXB), and Bangsa (BGS), were fed to broiler chicks in 21% protein diets containing 0.5% cholesterol in replicate trials. A corn-based diet, with added cholesterol, served as a control. Alternate diets were supplemented with β-glucanase (ENZ). β-glucan content ranged from 4.9% to 6.1% and soluble dietary fiber (SDF) from 3.6% to 7.5% in the barleys. Data from the two trials were pooled for statistical analysis by the SAS General Linear Models procedure. In body weight gain, chicks fed WSNP — ENZ were lower (P<0.05) than all other treatments. The β-glucanase supplement to the WXB and BGS barley tended to improve gains, but the differences were not significant for either barley. Feed to gain ratios were lowest (P<0.0001) for corn fed chicks and lower (P<0.05 toP<0.0001) for those fed the barley+ENZ diets compared to barley −ENZ. Chicks fed barley diets had lower (P<0.05) total serum cholesterol (TSC) and LDL-cholesterol than those fed corn diets, regardless of ENZ supplementation. For chicks on barley −ENZ diets, TSC levels for WSNP, WXB, and BGS were 146, 152, and 142 mg/dl respectively and for chicks on barley +ENZ diets, 218, 200, and 178 mg/dl. LDL-cholesterol levels followed the same trend and there was little difference in serum triglycerides. The BGS+ENZ lowered TSC 30% from the corn control compared to 10.7% and 18% for WSNP+ENZ and WXB+ENZ, suggesting additional hypocholesterolemic factors, possibly tocotrienol and SDF other than 1→3, 1→4 β-D-glucans.