Naked barley-Optimized recipe for pure barley bread with sufficient beta-glucan according to the EFSA health claims.

Naked barley is an underutilized crop that is suitable for the production of functional food: it contains remarkable amounts of β-glucans, which are well known for their blood cholesterol and short-time blood sugar regulating properties and their impact on weight regulation. The aim of the present work was to develop naked barley bread with satisfying sensory characteristics and good baking qualities that could augment the intake of dietary fiber, especially β-glucans and therefore meet the requirements of the EFSA health claim for β-glucans. The results of the multiple response optimization suggest that the elevated use of water, malt flour and margarine in pure naked barley bread augment the sensory attractiveness whereas the use of acidifier and pre-gelatinized flour has a negative effect on the sensory quality.

Introduction

Naked (Hordeum vulgare var. nudum) and hulled barley varieties share the same genetic background, except that the naked gene, nud, is expressed in the naked types. Naked barley may be two- or six-rowed, have short or long awns, vary in straw height, and occur in hooded (awnless)-type barley. Environmental growing conditions have major influences on kernel size and composition, but kernel size and shape are also genetically controlled characteristics (Newman and Newman, 2005).

The barley kernel consists of the caryopsis, the lemma, the palea, and the rachella. In contrast to hulled barleys, the caryopsis threshes free of the hull in the manner of common wheat. With the removal of the hulls, nutrients in the caryopsis increase in relative proportion because of reduction of fiber represented in the hulls (McGuire and Hockett, 1981). The caryopsis consists of the pericarp, testa, aleurone layer, endosperm and embryo. Incidences of increased protein and starch contents in naked barley genotypes are given by two studies conducted in the United States and Sweden (Oscarsson et al., 1997, Xue et al., 1997).

Naked barley is a good source of dietary fiber providing soluble and insoluble dietary fiber fractions (Bhatty, 1999, Izydorczyk et al., 2000). Mixed-linkage (1 → 3), (1 → 4)-β-d-glucans (hereafter termed as β-glucan) are a major part of the soluble dietary fiber (SDF) in barley. A previous study showed that the total β-glucan content is higher, whereas the insoluble dietary fiber content is significantly lower in naked barley (Xue et al., 1997) compared to hulled barley genotypes. Nevertheless, its content generally underlies a natural fluctuation depending on the variety and conditions before and after harvesting (Ehrenbergerová et al., 2008). High-amylose and waxy hulless barley contains approximately 7 or 8% β-glucans, whereas regular hulless barley comprises significantly less (4.6%) (Gao et al., 2009, Tiwari and Cummins, 2008).

Together with arabinoxylans, a fraction of partly soluble nonstarch polysaccharides (NSP) occurring in the cell walls, β-glucan has a great impact on cereal processing and product properties.

The positive effects of cereal β-glucans have been recently reviewed by Wood, 2010, Wood, 2007, with most of the data deriving from studies with oat β-glucans, followed by barley and rye. The mode of action of barley β-glucan in particular included the short-time blood sugar regulating effects of bread (Cavallero et al., 2002, Vitaglione et al., 2009) and of chapatis (Thondre and Henry, 2009), beneficial effects on the weight management by increasing satiety (Granfeldt et al., 1994, Nilsson et al., 2010) and on serum cholesterol levels (Shimizu et al., 2008, Smith et al., 2008, Talati et al., 2009). In 2005, the US Food and Drug Administration (FDA) concluded that a cause and effect relationship between the consumption of β-glucan and coronary heart disease lowering properties exists (21CFR101.81). In Europe, the European Food Safety Authority (EFSA) has indicated that it will allow claiming “regular consumption of β-glucans contributes to maintenance of normal blood cholesterol concentrations” (EFSA, 2009) by assuming that barley β-glucans have the same effects as oat β-glucans. In order to bear the claim, EFSA demands a quantity in food of at least 3 g/day of β-glucans from oats, oat bran, barley, barley bran, or from mixtures of non-processed or minimally processed beta-glucans in one or more servings. The positive effects of β-glucans are mainly attributed to its high viscosity in aqueous solution and thus increasing the viscosity of the contents within the intestinal tract (Jalili et al., 2000). Viscosity in the small intestine is determined by the concentration, molecular weight and solubility of β-glucan. At the moment, neither FDA nor EFSA substantiate their claims on the physicochemical properties. However, on a daily dosage of 3 g/day, scientific evidence unequivocally links the effects of β-glucan with its viscosity (Wolever et al., 2010), which is indirectly decreased due to degradation of the molecular weight during food processing (Åman et al., 2004, Andersson et al., 2008, Andersson et al., 2004, Lan-Pidhainy et al., 2007; Tosh et al., 2008).

It is anticipated, that, due to legislation, the interest of food producers and consumers in using naked barley for food purposes will increase. Nevertheless, despite the numerous health promoting properties of naked barley, barley flour is hardly used for human consumption at the moment. Reasons may be the poor baking properties of naked barley flours emerging from the sparsely formed gluten network. Additionally, the high concentration of β-glucan decreases the water availability for the gluten network and thus impairs the baking properties (Gill et al., 2002). The use of naked barley flour in bread is said to deteriorate the sensory properties, because it leads to a lower bread volume and a poorer crumb structure. Thus, the maximum level of barley flour recommended by Bhatty (1986) was 10% based on flour for yeast leavened breads. As a compromise between sensory attractiveness and additional health promoting benefits, barley flours substituted other flours at a maximum of equal parts in a study of Cavallero et al. (2002), albeit usual levels range from 15 to 20% (Berglund et al., 1992, Škribić et al., 2009).

The objective of this study was to develop an optimized formulation for bread based on 100% naked barley flour. For this, an experimental design and statistical multiple response optimization was used to obtain a dough with technologically feasible processing properties and bread with satisfying sensory attributes containing sufficient β-glucan to increase the daily intake and to be in accordance with the scientific opinion of EFSA.

Experimental

Materials

Two-rowed winter naked barley cv. Hiberna (originally released in Germany in 1993 by BPZ Saatenring) was conventionally grown in 2008 in Raasdorf (16°35′E, 48°13′N), Austria, on trial fields of the Experimental Station Gross-Enzersdorf. The baking experiments were accomplished with the following ingredients: Baking margarine was obtained from Senna Nahrungsmittel (Austria), whereas malt flour, pre-gelatinized flour (Risofarin) and acidifier (Diarol) were from Stamag Stadlauer Malzfabrik GmbH (Austria). Salt was obtained from Gustosal Salinen (Austria) and dry yeast (Saf-Instant yeast) from Lesaffre Austria AG (Austria).

The naked barley cv. Hiberna was milled with a MLU 202 roller mill (Bühler, Switzerland) as described by Andersson et al. (2003). The barley was not conditioned before milling and the feed rate for milling was approximately 5 kg/h. Six flour fractions (B1–B3, C1–C3) from the starchy endosperm were collected and merged to give a straight-run white flour. Brans and shorts were collected separately, but not used in this study. The flour was stored at 4 °C until use and allowed to equilibrate to room temperature before baking trials.

Analysis

Proximate analysis

Moisture and ash content of the barley flour were determined according to AOAC approved standard methods 940.56 and 920.153, respectively (AOAC, 1995). Crude protein was determined according to ICC-standard method 105/2 (ICC, 1998) using the factor 5.83 × N for conversion. Total starch (AOAC method 996.11), β-glucan (AOAC method 995.16) and dietary fiber content (AOAC method 991.43) were measured with enzymatic-gravimetric methods using commercially available test kits (Megazyme, Bray, Ireland). Water absorption was determined according to ICC-Standard method 115/1 (ICC, 1998). The β-glucan content was also measured in bread, in order to prove if the claim for helping to maintain a normal cholesterol level is enabled. For this, the bread was immediately shock frosted after baking and analyzed after thawing according to the manufacturer’s recommendation (Megazyme, Bray, Ireland).

Analysis of dough characteristics

To find out whether the investigated factors affected dough handling, dough stickiness was measured with the TA-XT2iR Texture Analyzer (Stable Micro Systems™, Great Britain) using the SMS/Chen-Hoseney Dough Stickiness Rig after kneading and after DFT as described by Grausgruber et al. (2003) with 10 replications per dough sample.

Analysis of bread characteristics

After baking, the breads were allowed to cool down and equilibrate at 20 °C and 50% rH in a climate chamber (MMM, Medcenter Einrichtungen GmbH, Germany) for 24 h ± 2 h.

To characterize the impact of the investigated factors the final bread volume, color, circumference along and across the bread were measured, each in 3 replications. Bread volume was measured by the rapeseed method (Chopin, France) according to ICC-Standard method 131 (ICC, 1998) and expressed on the basis of 1 kg flour. Color of crumb and crust were measured in the CIELAB color space (Micro Color, Dr. Lange, Germany).

The texture of bread cubes (40 × 40 × 25 mm l × w × h) using only bread crumb was assessed with the TA-XT2iR Texture Analyzer (Stable Micro Systems™, Great Britain) as previously described (Grausgruber et al., 2008). Maximum force (Fmax), the force at 25% compression (F25) and relative crumb elasticity (elasticityrel), defined as a proportion of Fres to Fmax, where Fres describes the force after holding at 40% compression for 60 s, were taken for statistical analyses (10 replications per bread sample).

Four trained persons assessed the sensory characteristics of the barley breads. Six parameters (appearance, browning, consistence of the crust, consistence of the crumb, mouthfeel and smell & taste) were scored from optimum (5) to poor (1).

Bread making

Considering preliminary trials the processing conditions were modified compared to ICC-standard method 131 (ICC, 1998) as follows: Each recipe was sized to give approximately 1600 g dough for three tin breads (135 × 95 × 70 mm, l × w × h). Firstly, DY was dissolved in 72 mL H2O (35 °C) containing 52.63 g L−1 sugar. Secondly, the remaining dry ingredients were placed in a mixing bowl (KM020 Titanium Major, Kenwood, UK) and mixed with the kneading hook at speed level 1 for 1 min. The DY solution was added slowly followed by the melted MA and the sucrose-salt solution (75 g sucrose and 75 g salt L−1) at speed level 1 within 1 min. Dough formation was completed by kneading for a further 3 min at speed level 2.5. The dough was proofed at 30 °C and 85% RH in a proofer (G66W, MANZ, Germany), scaled thereafter to 400 g portions and formed. Second proofing was performed in the baking tins at the same conditions as above. Finally, baking started at 230 °C top and bottom heat for 35 min in a baking station (BS60/3W, MANZ, Germany). The oven was steamed once after loading at the maximum level and the temperature was subsequently reduced to 180 °C.

Experimental design

27 recipes for barley bread were assessed with a fractional factorial Plackett-Burman experimental design. All ingredients were related to flour and are expressed in percent flour weight. The level of sucrose and salt was kept constant throughout the experiment and was 1.96 and 1.58%, respectively. The experimental factors studied were the two process parameters: DFT (min) and PP (min) and the six ingredient parameters: H2O, DY, AF, PGF, MF and MA. Each factor was tested at two levels, namely a high level denoted by (+1) and a low level denoted by (−1) with three replications of the center point (0) as listed in Table 1. The respective ranges of the factor levels have been evaluated in preliminary trials (data not published). The parameters used in the Plackett-Burman design and their influence on dough, bread and sensory attributes are shown in Table 2. For statistical analyses, the average value of each response variable was used and experimental factors, which were significant at a 5% level (P < 0.05) from the regression analysis were considered to have greater impact on the bread quality.

Table 1

Levels of the factors used in the experimental design for the production of barley bread and for the optimized recipe.

Factor level	Factor
	DFT [min]	PP [min]	H2O [%]	DY [%]	AF [%]	PGF [%]	MF [%]	MA [%]
−1	10	10	60.32	1.27	0.00	0.00	0.00	0.00
0	15	15	63.35	1.58	0.40	1.50	1.00	2.50
+1	20	20	66.38	1.89	0.80	3.00	2.00	5.00
Optimized	17.5	10	66.27	1.30	0.01	0.08	2.00	1.05

Values of ingredients are expressed as percent flour weight.

Table 2

Plackett-Burman design matrix (2^8 × 3/32) with observed values for physical and sensory attributes.

Run	Variables								Dough characteristics			Bread texture							Sensory attributes
	DFT	PP	H2O	DY	AF	PGF	MF	MA	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P
1	0	0	0	0	0	0	0	0	4.4	15.8	14.7	216.0	2289.7	35.3	36.9	0.34	78.9	74.8	2	2	2	2	3	1
2	1	−1	1	−1	−1	−1	1	1	5.0	23.8	24.1	223.2	5273.3	22.1	22.5	0.35	70.2	72.4	4	4	3	4	3	4
3	1	1	−1	1	−1	−1	−1	1	5.0	29.7	29.9	198.3	1908.9	42.8	45.5	0.34	73.0	73.5	2	3	2	3	2	3
4	−1	1	1	−1	1	−1	−1	−1	4.0	16.2	12.3	219.1	2223.9	33.2	37.8	0.32	85.3	73.8	4	1	3	2	3	1
5	1	−1	1	1	−1	1	−1	−1	5.0	14.8	11.8	221.2	2320.2	42.4	48.4	0.36	73.5	72.5	3	2	3	1	3	4
6	1	1	−1	1	1	−1	1	−1	4.1	13.8	13.4	210.8	2175.9	46.5	51.8	0.34	83.9	75.0	2	1	3	2	2	2
7	1	1	1	−1	1	1	−1	1	4.1	21.0	18.9	202.5	2275.2	43.6	44.3	0.28	76.4	73.1	2	2	2	2	3	2
8	−1	1	1	1	−1	1	1	−1	5.0	22.5	14.9	203.6	1969.4	31.2	35.2	0.38	76.2	71.1	3	2	4	2	3	4
9	−1	−1	1	1	1	−1	1	1	4.1	41.1	31.6	200.7	2190.1	31.5	34.0	0.32	73.8	72.7	3	3	2	4	3	1
10	−1	−1	−1	1	1	1	−1	1	4.1	10.8	10.5	185.0	2472.2	58.1	60.4	0.34	79.3	76.7	1	2	1	1	1	1
11	1	−1	−1	−1	1	1	1	−1	4.0	12.1	12.9	209.3	2313.8	60.3	67.5	0.32	82.4	74.2	1	1	2	2	1	1
12	−1	1	−1	−1	−1	1	1	1	5.1	19.1	17.1	195.6	1940.5	37.8	40.6	0.38	69.0	70.8	3	4	1	3	2	3
13	−1	−1	−1	−1	−1	−1	−1	−1	5.0	11.0	8.6	209.3	2331.3	51.7	56.0	0.37	80.2	76.8	2	2	4	1	2	3
14	0	0	0	0	0	0	0	0	4.4	16.0	17.4	211.3	2362.3	38.6	41.5	0.35	79.1	73.1	2	2	2	2	1	2
15	−1	1	−1	1	1	1	−1	−1	4.0	10.8	8.8	197.0	1804.9	72.4	78.2	0.33	82.8	74.8	1	1	1	1	1	2
16	−1	−1	1	−1	1	1	1	−1	4.1	11.5	10.8	200.6	1953.1	37.3	41.8	0.33	83.4	72.8	4	1	4	1	4	2
17	1	−1	−1	1	−1	1	1	1	5.1	16.6	12.3	214.5	2242.0	37.0	40.4	0.37	70.6	69.9	2	3	1	2	1	3
18	−1	1	−1	−1	1	−1	1	1	4.1	16.2	15.8	217.0	2229.7	43.6	45.8	0.33	79.0	73.4	2	2	1	1	1	1
19	−1	−1	1	−1	−1	1	−1	1	5.0	28.0	29.2	203.1	2218.0	35.0	36.6	0.35	71.2	71.2	3	3	2	3	2	3
20	−1	−1	−1	1	−1	−1	1	−1	5.0	19.5	16.8	140.9	1642.1	40.5	44.1	0.37	78.4	73.4	2	3	4	3	3	3
21	1	−1	−1	−1	1	−1	−1	1	4.0	16.2	13.7	204.9	2127.2	44.1	45.3	0.32	76.9	73.7	2	2	1	1	1	1
22	1	1	−1	−1	−1	1	−1	−1	5.0	14.8	11.0	221.7	2577.5	58.6	65.2	0.36	77.8	73.4	2	1	4	1	2	3
23	1	1	1	−1	−1	−1	1	−1	5.0	34.3	30.5	210.2	2051.3	27.1	30.5	0.37	77.8	70.2	2	2	3	3	1	3
24	−1	1	1	1	−1	−1	−1	1	5.0	21.9	18.9	214.2	2317.5	31.1	33.1	0.32	72.0	72.3	2	3	3	3	2	3
25	1	−1	1	1	1	−1	−1	−1	4.1	15.6	11.9	180.6	2642.3	40.4	45.2	0.31	81.5	73.6	2	1	4	1	2	2
26	1	1	1	1	1	1	1	1	4.1	25.1	22.3	214.8	2298.0	37.0	38.8	0.32	75.3	71.7	1	2	1	2	2	1
27	0	0	0	0	0	0	0	0	4.5	22.1	21.7	214.1	2341.2	34.8	37.5	0.34	81.3	73.0	2	2	2	2	3	2

[Low (−1); High (+1); Center point (0)] A: pH-value; B: stickiness after kneading; C: stickiness after DFT; D: circumference/kg flour; E: volume/kg flour; F: F25; G: Fmax; H: elasticityrel; I: L∗ crust; J: L∗ crumb; K: appearance; L: browning; M: consistence crust; N: consistence crumb; O: mouthfeel; P: smell & taste.

Optimization

Based on the results of the statistical design, the multiple response optimization procedure was used to optimize the bread recipe. Table 3 shows the impact factors for each of the observed variables: mouthfeel, smell and taste had the greatest importance followed by circumference and volume, elasticityrel, appearance and consistence of the crust. Generally, the highest priority was ascribed to the sensory evaluation of the naked barley bread whereas dough properties and colour of crust and crumb were graded less important.

Table 3

Direction of optimization and impact factor for each response variable of the multiple response optimization.

Observed variable	Direction of optimization		Impact factor
	Minimize	Maximize
Dough
pH-value		X	1
Stickiness after kneading	X		2
Stickiness after dft	X		2
Bread
Circumference/kg flour		X	4
Volume/kg flour		X	4
F25	X		3
Fmax	X		3
Elasticityrel		X	4
L∗ crust	X		2
L∗ crumb		X	2
Sensory
Appearance		X	4
Browning		X	2
Consistence crust		X	4
Consistence crumb		X	3
Mouthfeel		X	5
Smell & taste		X	5

Data analyses

All data were evaluated with STATGRAPHICS centurion XV® (Statpoint Technologies, Inc., Virginia) after eliminating outliers with Box-and-Whisker-Diagrams.

Results and discussion

Proximate composition

The proximate composition of the barley flour is presented in Table 4. Total starch was the main constituent, followed by protein and soluble dietary fiber of which β-glucan content was measured as 3.16% db. Insoluble dietary fiber, lipids and ash were found in minority with contents of 2.4, 1.7 and 1.1% db, respectively. Water absorption was 57.2%.

Table 4

Proximate composition of naked barley flour (cv. Hiberna).

Constituent	% db
Dry matter	88.00 ± 0.12
Ash	1.12 ± 0.02
Protein N × 5.83	9.62 ± 0.10
Fat	1.66 ± 0.02
Total starch	69.61 ± 1.54
Total β-glucan	3.16 ± 0.18
Dietary fiber, insoluble	2.36 ± 0.24
Dietary fiber, soluble	4.27 ± 0.03

Preliminary tests showed that pure barley bread of the cultivar Hiberna has a thin, cracked, light brown crust and a greyish, firm, compact and fine-pored crumb with a short bite and a dry mouthfeel during chewing.

The experimental design was used to identify ingredients that significantly affect the bread quality. As shown in Table 2, the wide variation of the response variables reflects the potential of optimization for a higher consumer preference. It is also reflected in Table 5 which summarizes the results of the ANOVA that DFT, PP and DY had no significant influence on any of the response variables. DFT and PP were set relatively low because preliminary tests showed that an extensive fermentation negatively influenced bread quality. DFT beyond 40 min resulted in a very smooth dough, leading to reduced bread volume and circumference. However, as a result of the optimization process, DFT was close to the high level and PP to the low factor level. The main reason for this can be seen in their effects on bread volume. A longer DFT increased the volume of the bread whereas longer PP decreased it, although both effects were not statistically significant (P = 0.113 and 0.197, respectively). DY negatively influenced the appearance of the bread at higher concentrations (P = 0.0566) and moreover, at the highest level a reduced bread volume and circumference were observed. These negative effects might be caused by an excessive rising in combination with a dough unable to hold the incorporated air. This results in a reduced volume and less appealing appearance of the bread.

Table 5

Summary of Regression analysis of Plackett-Burman design for prediction of significant experimental factors.

Observed parameter	Factor
	R2	DFT [min]	PP [min]	H2O [%]	DY [%]	AF [%]	PGF [%]	MF [%]	MA [%]
Dough
pH-value	98.78					−0.0000
Stickiness after kneading	59.05			+0.0070					+0.0182
Stickiness after DFT	57.84			+0.0209					+0.0065
Bread
Circumference/kg flour	34.24
Volume/kg flour	37.29
F25	87.43			−0.0000		+0.0010	+0.0006	−0.0004	−0.0034
Fmax	87.66			−0.0000		+0.0017	+0.0005	−0.0007	−0.0003
Elasticityrel	84.87			−0.0107		−0.0000		+0.0049	−0.0227
L∗ crust	89.87					+0.0000			−0.0000
L∗ crumb	69.83			−0.0039		+0.0043		−0.0041
Sensory
Appearance	53.86			+0.0049
Browning	90.32					−0.0000		+0.0067	+0.0000
Consistence crust	74.83			+0.0139		−0.0139	−0.0483		−0.0000
Consistence crumb	62.42					−0.0162		+0.0162	+0.0162
Mouthfeel	37.90			+0.0095
Smell&taste	80.93					−0.0000

Significant positive effects are marked with (+) and negative ones with (−), both are shown with the P-Value at the 95% confidence level.

H2O addition increased stickiness after kneading and stickiness after DFT which complicated dough processing. This finding is in agreement with others (Chen and Hoseney, 1995). A higher H2O addition softened the dough and consequently declined F25, Fmax and the elasticityrel, but had no impact on circumference and volume of the bread. With increasing amount of H2O, the crumb became more bread like and darker and affected the appearance, consistence of the crust and the mouthfeel positively.

The use of MF exhibited several positive effects on naked barley bread. It softened the bread (lower F25 and Fmax) and improved elasticity (elasticityrel) which led to a more bread-like texture. Furthermore, it ameliorated the crust in terms of browning and consistence.

MA softened the bread in regard to physical and sensory attributes (lower Fmax, F25 and better consistence of the crumb) and led to a better browning of the crust. On the other hand, an increased use of MA made the dough stickier and thus more difficult to process and negatively influenced the crust consistence.

The elevated use of AF predominantly deteriorated the sensory and textural attributes. Higher levels of acid went along with a worse browning, consistence of crust and crumb, smell and taste. Of the textural parameters, elasticityrel increased at higher AF levels.

PGF had no positive effects on any of the observed parameters. It hardened the dough and had a negative impact on the consistence of the crumb.

Table 1 summarizes the levels of the investigated factors after running the multiple response optimization. To estimate the reliability of the multiple response optimization, the predicted values for the naked barley bread were compared with the observed values. For instance, the predicted volume of the bread was 7% higher than the volume of the processed bread. The colour of the crust was 9% darker than predicted whereas the color of the crumb was 2% lighter. Generally, the results of the sensory evaluation were better than statistically predicted, which was positive because the emphasis of the experiment was set on sensory attractiveness.

Fig. 1A shows the naked barley bread processed according to the optimized formulation of the multiple response optimization. It illustrates the well developed bread volume, the light color of the crumb and its evenly distributed crumb structure.

Fig. 1

A. Pure naked barley bread produced according to the optimized recipe. B. Pure naked barley bread meets the health claim requirements for beta-glucan within the nutrition recommendation.

Fig. 1B shows that the β-glucan content of the naked barley bread is sufficiently high to meet the requirements of the recently passed EFSA health claim (3 g/day). One serving of bread (50 g) delivered 0.81 g of β-glucan, as measured enzymatically. The nutritional recommendation for bread intake is set between 200 and 300 g of bread per day (Elmadfa et al., 2009). Consequently, an intake of naked barley bread according to the nutritional recommendation goes along with a β-glucan intake that is sufficiently high to have health promoting effects. Thus, an intake of four servings of naked barley bread a day can make a contribution to a reduced blood cholesterol level.

Conclusions

The basic function of food to satiate and to provide macro- and micronutrients has become in the Western industrialized countries less and less important. Concurrently, the discussion of increasing the healthiness of consumers by changing eating habits or incorporating ingredients with health benefits has increased quickly.

With increasing prosperity and/or educational knowledge, additional attributes were ascribed to the consumption of food like sensorial sensation, social prestige or ethical aspects. Among these supplementary functions of food, the health-awareness of consumers is used to a high degree by the food and marketing industry for the promotion of existing and newly developed food products.

The perception that "healthy" foods are boring foods, the lack of information on packages as well as family pressures were seen as major barriers for dietary changes as observed by Baghurst (1992) in Australia. A few years later, these barriers have not changed much (Lopez-Azpiazu et al., 1999).

A further barrier for increasing the consumption of whole grain in particular is the still increasing knowledge about the biochemical mechanisms behind the health benefits. In the late 80s, Bhatty (1986) concluded that the removal of β-glucan by plant breeding could enhance the use of naked barley in food and feed applications, whereas nowadays it is assumed that exactly the contrary is the case.

Since then, in most studies attention was mainly focused on the polysaccharide moiety, while the potential role of whole grain antioxidants was considered less up to now. The newly introduced term “dietary fiber-antioxidants” assumes that the beneficial effects attributed to the cereal dietary fiber are due not only to the polysaccharide moiety, but also to the associated polyphenolic compounds (Vitaglione et al., 2008).

The present experiments showed that the baking quality of naked barley flour is sufficient to bake pure naked barley bread. Thus, naked barley is an interesting alternative for commonly used grains and could contribute to a higher diversity in human nutrition.

Facts which strongly support the use of naked barley are the non-uniform distribution of dietary fiber within the kernel and especially its high content of β-glucans. As a consequence, white barley flour fractions contain a sufficiently high amount of soluble dietary fiber. This being the case, there is no need for using whole meal flour to obtain high dietary fiber cereal based products when naked barley is utilized for food production. Thus, the current preference of consumers for white bread may be met more easily until eating habits have changed due to an increased health consciousness and scientific evidence.