Carotenoids and tocols content in genotypes of colored barley

Carotenoids and tocols of 20 genotypes of colored barley divided into three groups (A, B, C) were investigated. These included 16 F8 recombinant inbred lines obtained from crosses of four parental lines: 2005 FG, K4-31, L94 and Priora. The aim of the present study was to identify, quantify and profile characterize of tocols and carotenoids. Tocols profile is characterized by the prevalence of tocotrienols on tocopherols. The α-tocotrienol was the most represented tocol isomer, contributing about 53.03% of the total content. The highest α-tocotrienol content (33.67 μg g-¹) was found in the blue naked parental genotype 3007 (C-Group). The most abundant carotenoid was lutein on average 86% of total followed by zeaxanthin 10% and by α-carotene 3.40%. The Priora cultivar (C-Group) was the genotype with the highest lutein content (4.10 μg g-¹). The study found great variability in the content of carotenoids and tocols along the lines of each group.     

The effects of extrusion on the content and properties of dietary fibre components in various barley cultivars

Wholemeal flour from five Czech spring barley materials was processed in a single-screw extruder at 130 °C, addition of 20% water and a screw speed of 220 rpm. Two barleys (AF Cesar, AF Lucius) were hulless cultivars with a standard starch composition, while three barleys (KM 2624, KM 2460-1, KM 2460-2) were hulled waxy lines. The effect of extrusion on content of different dietary fibre fractions was determined. Also the changes of the molar mass of β-glucan were studied. Regardless of the barley genotype (standard starch or waxy), the extrusion had no significant effect on arabinoxylan content. A significantly higher beta-glucan and soluble dietary fibre content in barley cultivars with standard starch composition was observed after extrusion. The content of insoluble dietary fibre decreased significantly in all extruded flours. The molar mass of water-extractable beta-glucan increased independently of the barley variety after extrusion. But the increase in beta-glucan extractability due to extrusion was not observed.     

Effect of Cultivar, Year Grown, and Cropping System on the Content of Tocopherols and Tocotrienols in Grains of Hulled and Hulless Barley

In a three-year period (2000–2002) total tocols (tocopherols and tocotrienols), content of vitamin E and its isomers (α-, β+γ-, δ-tocopherols and tocotrienols) were assessed in grain of 13 barley genotypes. The highest content of tocols (60.3–67.6 mg kg⁻¹) and content of vitamin E (Vitamin E equivalent—18.0–20.1 mg kg⁻¹) were determined in the waxy varieties Wanubet, Wabet, and Washonubet. Standard varieties, i.e. of a malting type (Krona and Kompakt), had statistically significantly lower content of tocols (49.9 and 53.6 mg kg⁻¹) and vitamin E (15.7–16.1 mg kg⁻¹) compared to the waxy varieties. The hulless waxy variety Washonubet had statistically significantly higher total content of tocols (67.6 mg kg⁻¹) and α- tocotrienols isomer (42.1 mg kg⁻¹) versus all other genotypes in the set. Chemical treatment and fertilization statistically significantly increased the content of tocols (by 4.7 mg kg⁻¹), vitamin E (by 1.9 mg kg⁻¹), isomer α-tocopherol (by 0.9 mg kg⁻¹) and isomer α- tocotrienols (by 3.3 mg kg⁻¹). The average values of α-tocopherols and α-tocotrienols in the set were 6.7 mg kg⁻¹ and 29.7 mg kg⁻¹, respectively. Some of the reciprocal lines created by us from the malting and waxy varieties are suitable for food use for high contents of all tocopherols and α-tocotrienols.     

Optimization of air classification for the production of β-glucan-enriched barley flours

Barley grains contain a relevant amount of soluble fibre (i.e. β-glucans) and can be used for production of foods with healthy functions. To produce barley flours enriched in β-glucans, grain micronization and air classification of the flour was used, and a method to predict the relationship between the yield of the enriched flour and its β-glucan content was developed. This method is based on a series of sortings of micronized flour, with a progressive increase in the yield of a selected fraction; a curve for β-glucan enrichment vs. yield can then be calculated. Thus, the most suitable combination of yield and β-glucan content can be chosen. We tested this approach on two hull-less barleys with different starch type, and obtained barley flour fractions with twice the β-glucan concentration that the grain had. Enriched flour fractions with 11.2 and 15.6% β-glucans were obtained from cultivars Priora (hull-less) and CDC Alamo (waxy, hull-less), respectively, with a good flour yield (about 30%). We suggest that our method can be adopted for finely tuning the enrichment process to meet the industry's needs.     

Grain composition of Virginia winter barley and implications for use in feed,food, and biofuels production

Grain compositional components impacting barley (Hordeum vulgare L.) use in food, feed and fuel products, must be combined with improved agronomic traits to produce a commercially viable barley cultivar. Little current information is available on grain composition and variability among winter barley genotypes. This study was conducted to determine the variability among modern hulled and hulless winter barley genotypes in grain composition. Barley types varied significantly in grain and kernel weight, starch, beta-glucan, oil and ash content, but not in protein concentration. Hulless barley had significantly higher grain test weight and starch concentration than hulled and malting types, and significantly higher beta-glucan than malting barley. Hulless barley had significantly lower kernel weights, oil, and ash concentrations than hulled and malting types. Higher starch and lower fiber and ash in grain of hulless barley versus hulled feed or malting type barley are characteristics that increase hulless barley desirability. Selection for high starch concentration among all barley types is feasible and will facilitate development of barley cultivars better suited for use in feed, malt, and ethanol production.     

不同类型大麦品种籽粒中酚酸类化合物含量的差异

为了探明不同类型大麦品种籽粒中酚酸类化合物含量的差异,采用超声辅助提取、高效液相色谱测定的方法对15个大麦品种（系）籽粒中的13种酚酸含量进行了比较分析。结果表明,大麦籽粒中的酚酸类化合物主要是羟基苯甲酸衍生物,羟基肉桂酸衍生物含量较少。不同类型大麦品种籽粒中酚酸类化合物的含量存在极显著的差异,黑皮大麦籽粒中总羟基苯甲酸衍生物（THBA）、总羟基肉桂酸衍生物（THCA）和总酚酸（TPA）的含量均高于非黑皮大麦;二棱大麦籽粒中THBA、THCA和TPA的含量均高于多棱大麦;皮大麦籽粒中THCA和TPA的含量高于裸大麦,但THBA的含量与裸大麦无显著差异。另外,与裸大麦相比,皮大麦籽粒中含有更为丰富的酚酸种类。     

Folate in barley grain and fractions

Wholegrain cereals are good sources of folate. However, little is known about folate in barley. In this study, total folate was analysed in five hulled Finnish barley cultivars from three harvesting years (2006–2008). In addition, different fractions were produced from two hulled cultivars by scarification and from mixes of hulled cultivars by industrial milling. Total folate was determined in all samples with a microbiological method and vitamer distribution in scarification and industrial milling fractions, using HPLC or UPLC. Limited variation was observed in the total folate content of the five cultivars. The average contents of the three harvest years ranged from 563 to 773 ng/g dm. Fractions containing germ and outer layers were the richest in folate. The highest total folate content in the scarification fractions was up to 1710 ng/g dm. The total folate content of the hull fraction obtained by dehulling 10% of the grains with an industrial pearler was almost 4-fold compared to the corresponding dehulled grain. This hull fraction is normally not used as food. The main folate vitamers in the fractions were 5-HCO-H₄folate, 5-CH₃-H₄folate, 5,10-CH⁺-H₄folate, and 10-HCO-PGA. Folate content could be enhanced naturally by introducing folate-rich fractions of barley into cereal products.     

Tocols and carotenoids of einkorn,emmer and spring wheat varieties: Selection for breeding and production

Einkorn (Triticum monococcum L., subsp. monococcum), emmer (Triticum dicoccum Schuebl [Schrank], subsp. dicoccum) and spring bread wheat (Triticum aestivum L.) may be rich in lipophilic antioxidants (tocols and carotenoids), and therefore potential food sources with good nutritional properties. The aim of the present study was to determine the contents of major lipophilic antioxidants beneficial for human health in wheat varieties and landraces for breeding and production. In field experiments over two years, fifteen einkorn, emmer and spring wheat varieties were analysed for the contents of tocols and carotenoids in grain. A high carotenoid content (lutein, zeaxanthin, β-carotene) was typical for the selected einkorn genotypes. Among the analysed wheat species, the highest content was of β-tocotrienol, especially in the einkorn accessions. α-Tocotrienol was abundant in einkorn and emmer wheat species. Higher contents of α- and β-tocopherols were characteristic of spring and emmer wheats. δ-Tocotrienol has been detected for the first time in einkorn and some emmer accessions, although in low concentrations. Significant effects of genotype on the contents of carotenoids and tocols were found with einkorn differing from emmer and spring wheats. The year of cultivation had less effect on the contents of carotenoids and tocols. Selected accessions of einkorn with high contents of carotenoids and tocotrienols as well as spring and emmer wheats with higher contents of tocopherols are good sources of antioxidants with potential health promoting benefits for the production of nutritionally enhanced foods.     

A developmental profile of tocol accumulation in oat seeds

Oats are a good source of many vitamins and minerals, including compounds that collectively constitute vitamin E, the tocols. Tocols are comprised of two subgroups, tocopherols and tocotrienols. Due to their potent antioxidant properties, attention has been given to the health benefits of tocols in oats. However, little is known about developmental aspects of their accumulation. Moreover, aside from their role in protecting membranes from oxidative damage, their possible physiological roles in planta have largely gone uninvestigated. In this study, we quantified tocol accumulation at five time points during oat seed development, and also compared tocol concentration and composition in the whole seed both to endosperm and embryos at a late stage of seed development. The temporal pattern of accumulation of the tocol subgroups was different. Both tocotrienols and tocopherols steadily increased over the course of seed development; however, tocotrienol progression was sigmoidal and tocopherol linear. By the end of seed development, tocotrienols were the most abundant tocol both in whole seed and in seed with embryos removed. In contrast, embryos contained higher concentrations of tocopherols than tocotrienols late in seed development. Differences in both temporal and spatial distribution during seed development suggest distinct roles for tocotrienols and tocopherols.     

Antioxidant activity of small grain cereals caused by phenolics and lipid soluble antioxidants

In this study, the content of soluble, free forms of phenolic compounds (total phenolics, flavonoids, PVPP (polyvinylpolypyrrolidone) bound phenolics, proanthocyanidins and phenolic acids), as well as the content of carotenoids and tocopherols, were determined in whole grains of bread and durum wheat, rye, hull-less barley and hull-less oat, each represented with four genotypes. Antioxidant activity was evaluated as radical scavenging activity with DPPH (2,2-diphenyl-1-picrylhydrazyl) reagent, as well as by hydrogen transfer reaction (reduction power) based on the reduction of Fe³⁺. Generally, a considerable variation in antioxidant activities and phytochemical contents was observed between the cereals. Remarkably higher DPPH radical scavenging ability and reducing power were detected in hull-less barley, followed by rye and hull-less oat and durum and bread wheat, indicating that small grain species have different major antioxidants with different properties. Hull-less barley had the highest content of total free phenols, flavonoids, PVPP bound phenolics and contained flavan-3-ols, not found in other species. Hull-less oat had the highest content of tocopherols, very high content of yellow pigments and PVPP bound phenolics. Ferulic acid was the major free phenolic acid in small grain cereals tested. The relationship between the content of soluble phenols, as well as reducing power and DPPH^• scavenging activity are also considered.     

Mass spectrometry imaging of BARLEYmax fructooligosaccharides

BARLEYmax is a novel hull-less barley cultivar lacking activity of a key enzyme required for starch synthesis (SSIIa), resulting in a grain with reduced total starch, higher dietary fiber, and higher fructan content. In this study, we examined the quantitative differences in fructan among 2 hull-less barley lines (BARLEYmax and Mannenboshi) and 2 peeled barley lines (Glutinous barley rice and Hindmarsh). We found that BARLEYmax had a higher fructan content, particularly 2 types of fructooligosaccharides (FOS), namely kestose and nystose, the important components of fructan that have some beneficial effects for human health. We established a mass spectrometry imaging (MSI) method to further investigate the content and localization of FOS in the barley lines. We found that kestose, nystose, and fructosyl-nystose showed increased molecular ion intensities in BARLEYmax compared with those in other barley lines. These results confirmed that the loss of SSIIa activity in BARLEYmax leads to a decrease in starch in the cytoplasm and an increase in fructan in the vacuole as an energy store. Overall, these findings demonstrate that MSI analysis is helpful for understanding FOS localization in cereal grains and for visual comparison among matured grains.     

Predicted truly absorbed protein supply to dairy cattle from hulless barley (Hordeum vulgare L.) with altered carbohydrate traits with multi-year samples

Hulless barley breeding lines varying in amylose (1–20% DM) and β-glucan content (5–10% DM) have been developed at the Crop Development Centre, Canada. The objectives of this large-scale study were to 1) determine and confirm the effect of these new hulless barley lines (zero-amylose waxy, CDC Fibar; 5%-amylose waxy, CDC Rattan; normal-amylose, CDC McGwire and high-amylose, HB08302) with altered carbohydrate traits on 1) metabolic characteristics of protein; 2) intestinal digestion of various nutrients and 3) modeling nutrient supply from these barley varieties by using NRC Dairy 2001 model and DVE/OEB system. CDC Copeland was included as a hulled barley control. Among the hulless barley lines, CDC Fibar contained the highest and CDC McGwire contained the lowest total digestible protein (TDP: 147 vs. 116 g/kg DM). HB08302 was greater (P < 0.05) in intestinal digestible protein (IDP: 40.6% RUP) but relatively lower (P < 0.05) in total digestible protein (TDP: 120 g/kg DM). Compared with hulless barley, hulled barley showed relatively lower (P < 0.05) intestinal digestible protein (38 vs. 53 g/kg DM) and total digestible protein (102 vs. 129 g/kg DM). In modeling nutrient supply from the DVE/OEB system, the results showed hulled barley was lower (P < 0.01) in true protein supplied to the small intestine (TPSI: 127 vs. 142 g/kg DM), lower in truly absorbed rumen bypassed feed protein in small intestine (ABCP^DVE: 43 vs. 58 g/kg DM), lower in truly absorbed protein in the small intestine (DVE: 95 vs. 111 g/kg DM), and lower in degraded protein balance (OEB^DVE: −39 vs. −23 g/kg DM) than the hulless barley lines but greater (P < 0.01) in undigested inorganic matter (9 g/kg DM). From NRC Dairy 2001 model, CDC Fibar was greater (P < 0.05) in degraded protein balance (OEB^NRC: −30 g/kg DM) and metabolizable protein (MP: 118 g/kg DM) than the other hulless barley lines, while hulled barley was relatively lower (P < 0.01) in total metabolizable protein (MP: 83 vs. 105 g/kg DM). Our correlation results suggested that TDP was negatively correlated to amylose (r = −0.85, P < 0.001) but positively correlated to β-glucan level (r = 0.74, P < 0.001) in hulless barley cultivars. The DVE and OEB^DVE as well as MP were negatively correlated (P < 0.05) to amylose level but positively correlated to β-glucan level (P < 0.05). In conclusion, altered carbohydrate traits in the hulless barley varieties have the potential to increase intestinal nutrient availability to ruminants and significantly improved the truly absorbed protein supply to dairy cattle compared to hulled barley. Hulless barley with lower amylose and higher β-glucan level could provide greater (P < 0.05) truly digested protein in the small intestine, better synchronized available energy and N and increase metabolizable protein supply to ruminants.     

Predicted truly absorbed protein supply to dairy cattle from hulless barley (Hordeum vulgare L.) with altered carbohydrate traits with multi-year samples

Hulless barley breeding lines varying in amylose (1–20% DM) and β-glucan content (5–10% DM) have been developed at the Crop Development Centre, Canada. The objectives of this large-scale study were to 1) determine and confirm the effect of these new hulless barley lines (zero-amylose waxy, CDC Fibar; 5%-amylose waxy, CDC Rattan; normal-amylose, CDC McGwire and high-amylose, HB08302) with altered carbohydrate traits on 1) metabolic characteristics of protein; 2) intestinal digestion of various nutrients and 3) modeling nutrient supply from these barley varieties by using NRC Dairy 2001 model and DVE/OEB system. CDC Copeland was included as a hulled barley control. Among the hulless barley lines, CDC Fibar contained the highest and CDC McGwire contained the lowest total digestible protein (TDP: 147 vs. 116 g/kg DM). HB08302 was greater (P < 0.05) in intestinal digestible protein (IDP: 40.6% RUP) but relatively lower (P < 0.05) in total digestible protein (TDP: 120 g/kg DM). Compared with hulless barley, hulled barley showed relatively lower (P < 0.05) intestinal digestible protein (38 vs. 53 g/kg DM) and total digestible protein (102 vs. 129 g/kg DM). In modeling nutrient supply from the DVE/OEB system, the results showed hulled barley was lower (P < 0.01) in true protein supplied to the small intestine (TPSI: 127 vs. 142 g/kg DM), lower in truly absorbed rumen bypassed feed protein in small intestine (ABCP^DVE: 43 vs. 58 g/kg DM), lower in truly absorbed protein in the small intestine (DVE: 95 vs. 111 g/kg DM), and lower in degraded protein balance (OEB^DVE: −39 vs. −23 g/kg DM) than the hulless barley lines but greater (P < 0.01) in undigested inorganic matter (9 g/kg DM). From NRC Dairy 2001 model, CDC Fibar was greater (P < 0.05) in degraded protein balance (OEB^NRC: −30 g/kg DM) and metabolizable protein (MP: 118 g/kg DM) than the other hulless barley lines, while hulled barley was relatively lower (P < 0.01) in total metabolizable protein (MP: 83 vs. 105 g/kg DM). Our correlation results suggested that TDP was negatively correlated to amylose (r = −0.85, P < 0.001) but positively correlated to β-glucan level (r = 0.74, P < 0.001) in hulless barley cultivars. The DVE and OEB^DVE as well as MP were negatively correlated (P < 0.05) to amylose level but positively correlated to β-glucan level (P < 0.05). In conclusion, altered carbohydrate traits in the hulless barley varieties have the potential to increase intestinal nutrient availability to ruminants and significantly improved the truly absorbed protein supply to dairy cattle compared to hulled barley. Hulless barley with lower amylose and higher β-glucan level could provide greater (P < 0.05) truly digested protein in the small intestine, better synchronized available energy and N and increase metabolizable protein supply to ruminants.     

Chemical Composition and Microstructure of Two Naked Waxy Barleys

Two naked waxy barley cultivars, Bz 489-30 and Prowashonupana were analysed in order to study the chemical composition and the microstructure. Prowashonupana contained more protein, fat and ash, and less starch than Bz 489-30. The content of mixed-linked β-glucan was almost three times higher in Prowashonupana (14·9%) than in Bz 489-30 (5·6%), but extractability at 40 °C was much lower. Microscopy studies showed that kernels and endosperm cells of Prowashonupana were irregular, and that cell walls were thicker with a higher content of mixed-linked β-glucan than in Bz 489-30. In both barleys the sub-aleurone layer contained black starch granules, indicating a higher amylose content in this structure compared to the rest of the kernel. Starch was isolated from both barleys using two different procedures and analysed for amylose content. The amylose content was higher, while volume % of A-granules was lower and mean diameter of A-granules was smaller in starch isolated from Prowashonupana than from Bz 489-30. Both composition and yield of starch were however influenced by the isolation procedure used. The procedure which gave higher starch yield resulted in a higher amylose content, probably because of greater recovery of starch from outer parts of the kernel with a higher amylose content.     

啤酒大麦品种的蛋白质含量和环境变异研究

大麦是兼食用、饲用、酿造于一体的作物 ,蛋白质含量是各种用途大麦的重要品质性状。本研究在我国南方冬大麦区设置 8个试点 ,测定分析了 10个大麦品种在各试点种植两年的蛋白质含量。结果表明 ,蛋白质含量在品种间、地区间以及年度间均存在着显著差异 ,两年平均 ,浙农大 6号和盐引一号分别为蛋白质含量最高和最低的品种 ,泰安和杭州是蛋白质含量最高和最低的试点。年度间和品种与地区及品种与年份之间的互作均达极显著水平。     

Effects of Cultivar and Environment on β-(1,3)-(1,4)-D-glucan Content and Acid Extract Viscosity of Spanish Barleys

The acid extract viscosities and β-glucan contents of ten two- and six-rowed barley cultivars grown at seven locations in three consecutive years in Spain were studied in the present work. The viscosities varied from 2·4 to 24·8 centistokes (cSt) and the mean value was 6·4 cSt. The average β-glucan content of barleys determined by HPLC was 3·5% with a range of 1·9–5·5%. Significant differences were found in both β-glucan content and acid extract viscosity between different cultivars, locations and years. The β-glucan contents and viscosities of winter cultivars were higher than those of spring. Cvs. Barbarrosa and Hatif de Grignon were the genotypes with the highest values for both parameters, while cv. Beka had the lowest viscosity and β-glucan content. Environmental factors influenced both parameters. The acid extract viscosities of barleys were correlated negatively with the amount of precipitation (r=−0·754;P<0·05). Barleys grown in wet and rainy areas (Girona and La Coruña) had lower viscosity values.     

Barley Bulgur: Effect of Processing and Cooking on Chemical Composition

Three barley cultivars (Hordeum vulgareL.) were processed into bulgur by pressure cooking or cooking at atmospheric pressure. The effect of processing on levels of thiamine, riboflavin, minerals (Fe, Cu, Zn, Mn, Ca, Mg) as well as the phytic acid and β-glucan was investigated. Significant decreases (p<0·05) were observed in ash, riboflavin and thiamine contents during bulgur processing. Neither the cooking methods nor the dehulling process had significant influence on the content of Fe, Cu, Zn or Mg. However, the Mn and Ca content of the bulgurs were significantly (p<0·05) lower compared with the corresponding raw barleys. For all cultivars total P and phytate P contents of the bulgurs were significantly (p<0·05) lower compared with the corresponding raw barleys. In contrast, levels of β-glucan were significantly higher in processed bulgur vs raw barley. Protein contents of the samples did not change significantly during bulgur processing. Bulgur processed from barley appeared to retain most of the nutritional value of raw barley, in particular it showed high levels of soluble dietary fibre.     

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 -glucanase (ENZ). -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 -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 13, 14 -D-glucans.Contribution No. J-2487, Montana Agricultural Experiment Station. This research was supported, in part, by a grant from the Montana Wheat and Barley Committee, Great Falls, MT, U.S.A.     

Metabolic characteristics in ruminants of the proteins in newly developed hull-less barley varieties with altered starch traits

Recently, new varieties of hull-less barley have been developed with altered carbohydrate traits. To our knowledge, there is no study on metabolic characteristics in ruminants of the proteins in the newly developed hull-less barley varieties. The objectives of this study were to: compare metabolic characteristics of the proteins of zero-amylose waxy (CDC Fibar), low-amylose waxy (CDC Rattan), high-amylose (HB08302), and normal starch (CDC McGwire) hull-less barley. In situ animal trials were carried out to generate the original rumen fermentation data for modeling nutrient supply to dairy cattle by using two dairy nutrition models – Dutch DVE/OEB system and NRC 2001. The major comparisons were made in terms of i) truly absorbed protein in the small intestine (DVE or MP, and ii) degraded protein balance (DPB). The study revealed that zero-amylose waxy hull-less barley was superior (P < 0.05) in both DVE (123 vs. 117, 114, 103 g kg⁻¹ DM) and MP (112 vs. 93, 96, and 87 g kg⁻¹ DM) when hull-less barley was evaluated as a single feed for dairy cattle. All of four hull-less barley varieties had negative DPB (DPB^OEB; −37.4, −17.1, −30.2, and −28.2 g kg⁻¹ DM for normal starch, zero-amylose waxy, waxy, and high-amylose cultivar, respectively), indicating the potential N shortage. In conclusion, the alteration of starch structure in granule provided a relatively balanced energy and protein for microbial synthesis in the rumen. The DVE and DPB predicted by using the DVE/OEB system can be explained (r² > 0.76) by the equivalent parameters, predicted by using the NRC 2001 model. The alteration of starch structure in granule affects metabolic characteristics of the proteins of hull-less barley in ruminants.     

Assessment of biochemical markers identified in wheat for monitoring barley grain tissue

The possible use of specific biochemical compounds identified in wheat grains was evaluated for monitoring barley grain tissues during fractionation. First barley grain anatomy was studied through microscopic observation and quantification of the relative proportion of each anatomical part in four distinct barley samples from both hulled and hulless genotypes. As expected from cereal phylogeny and irrespective of the possible presence of hull, common features were observed between barley and wheat grains, but the aleurone layer predominated in the outer layers. The specific location of the compounds identified in wheat was established. Phytic acid was specifically localized in the aleurone layer and alkylresorcinols in the composite layer containing the testa, even if their concentration differed from that observed in wheat grain tissues. Thus, these two markers identified in wheat can be used to monitor the corresponding barley tissues, independent of the presence of hulls. Conversely, phenolic compounds, either ferulic acid trimer or p-coumaric acid, cannot be used to monitor respectively the outer pericarp or the aleurone cell walls in barley grains. p-coumaric acid was identified as an efficient marker of the hull and could be used to distinguish hulled or hulless barley grains and to help monitor the dehulling process.