Variations in the composition of oats and barley grown in Wales: (Proximate constituents,available carbohydrate and “1,000 grain weights”)

Proximate analytical data and estimated metabolisable energy values (for poultry) for 171 samples of oats and 179 samples of barley for 3 seasons are presented. The results showed that both grains were extremely variable in crude protein content, the barley rather more so than oats. In contrast, both cereals were relatively constant in calculated metabolisable energy values with oats being more variable than barley. Some of the more important implications of these results in practical livestock feeding are discussed. It is concluded that it would be worthwhile for farmers who home-mix cereals with concentrates to have samples of grain analysed in order to admix concentrates most effectively and economically. Techniques of sampling however, require to be clearly understood for worthwhile results.     

Influence of exogenous enzyme supplementation on energy utilisation and nutrient digestibility of cereals for broilers

The influence of a microbial phytase, produced by solid‐state fermentation, on the apparent metabolisable energy and ileal digestibility of phosphorus, nitrogen and starch in sorghum, maize, wheat and barley was examined using 4‐week‐old broilers. For wheat and barley, the influence of phytase, individually or in combination with glycanases, was also evaluated. Microbial phytase improved (p < 0.05) apparent ileal phosphorus digestibility in all cereals. Phytase supplementation improved (p < 0.05) the apparent metabolisable energy of maize and barley by 2.6 and 7.8%, respectively. Numerical improvements in apparent metabolisable energy were observed in sorghum (1.9%) and wheat (2.1%), but were not statistically significant (p > 0.05). Further improvements (p < 0.05) in the apparent metabolisable energy of wheat and barley were observed when the phytase was combined with glycanases. However, the observed improvements in apparent metabolisable energy were not always associated with enhanced ileal digestibility of protein and starch. Copyright © 2004 Society of Chemical Industry     

Surveillance of stored grain from the 1997 harvest in the United Kingdom for ochratoxin A

This survey examined 306 samples of farm-stored wheat, barley and oats as received at, or tested by, central grain depots in the UK. Samples were taken from lorries or from stored grain using the existing inhouse procedures used for quality checking and examined for ochratoxin A using a fully validated analytical HPLC method with a detection limit of 0.1 μg/kg. Ochratoxin A was detected in 21 % of the samples examined, with barley more frequently contaminated than wheat. Mean concentrations of ochratoxin A found for all samples were 0.69 μg/kg in barley, 0.29 μg/kg in wheat and 0.15 μg/kg in oats. The highest concentration found was 17.8 μg/kg in a barley feed although concentrations of 81 and 30 μg/kg were found in 'reject-grade' wheat samples whose results were excluded from the main survey. In summary, 2.7 and 0.3 % of samples exceeded concentrations of 5 and 10 μg/kg respectively. There appeared to be significant relationships between ochratoxin A concentrations and moisture content, storage time and geographical area. Although conditions at harvest in 1997 were quite variable countrywide and often wet, results were similar to those found in earlier surveys carried out in the UK.     

The apparent metabolisable energy and amino acid digestibility of wheat,triticale and wheat middlings for broiler chickens as affected by exogenous xylanase supplementation

The effects of a commercial xylanase preparation on the apparent metabolisable energy and ileal amino acid digestibility values of wheat (n = 2), triticale and wheat middlings for five-week-old broiler chickens were investigated. The apparent metabolisable energy and ileal amino acid digestibilities in wheat 1 (new season) and wheat 2 (old season) were improved (P < 0.05) by the supplemental enzyme. The apparent metabolisable energy values (MJ kg⁻¹) of wheat 1 and wheat 2, without or with the enzyme, were 13.71 and 14.40, and 14.28 and 15.34, respectively. The average digestibilities of the 15 amino acids in wheat 1 and wheat 2, without or with the enzyme, were 0.85 and 0.91, and 0.85 and 0.90, respectively. Exogenous xylanase was without effect (P > 0.05) on the apparent metabolisable energy values of triticale and wheat middlings. Although numerical advantages in the amino acid digestibility of triticale and wheat middlings were observed with enzyme addition, the differences were not significant (P > 0.05) except for phenylalanine, lysine and glycine in the wheat middlings. © 1999 Society of Chemical Industry     

Effects of replacement of barley with oats on milk fatty acid composition in dairy cows fed grass silage-based diets

This study consists of milk fatty acid (FA) data collected during 2 in vivo experiments. For this study, 8 cows from each experiment were included in a replicated 4 × 4 Latin square design. At the start of experiment 1 (Exp1) cows were at (mean ± standard deviation) 87 ± 34.6 d in milk, 625 ± 85.0 kg of body weight, and 32.1 ± 4.17 kg/d milk yield and at the start of experiment 2 (Exp2) cows were at 74 ± 18.2 d in milk, 629 ± 87.0 kg of body weight, and 37.0 ± 3.2 kg/d milk yield. In Exp1, we examined the effects of gradual replacement of barley with hulled oats (oats with hulls) on milk FA composition. The basal diet was grass silage and rapeseed meal (58 and 10% of diet DM, respectively), and the 4 grain supplements were formulated so that barley was gradually replaced by hulled oats at levels of 0, 33, 67, and 100% on dry matter basis. In Exp2, we examined (1) the effects of replacing barley with both hulled and dehulled oats (oats without hulls) and (2) the effects of gradual replacement of hulled oats with dehulled oats on milk FA composition. The basal diet was grass silage and rapeseed meal (60 and 10% of diet DM, respectively), and the 4 pelleted experimental concentrates were barley, hulled oats, a 50:50 mixture of hulled and dehulled oats, and dehulled oats on dry matter basis. In Exp1, gradual replacement of barley with hulled oats decreased relative proportions of 14:0, 16:0, and total saturated FA (SFA) in milk fat linearly, whereas proportions of 18:0, 18:1, total monounsaturated FA, and total cis unsaturated FA increased linearly. Transfer efficiency of total C18 decreased linearly when barley was replaced by hulled oats in Exp1. In Exp2, relative proportions of 14:0, 16:0, and total SFA were lower, whereas proportions of 18:0, 18:1, monounsaturated FA, and cis unsaturated FA were higher in milk from cows fed the oat diets than in milk from cows fed the barley diet. Moreover, in Exp2, gradual replacement of hulled oats with dehulled oats slightly decreased the relative proportion of 14:0 in milk fat but did not affect the proportions of 16:0, 18:0, 18:1, total SFA, monounsaturated FA, trans FA, or polyunsaturated FA. In Exp2, transfer efficiency of total C18 was lower when cows were fed the oat diets than when fed the barley diet and decreased linearly when hulled oats were replaced with dehulled oats. Predictions of daily CH₄ emissions (g/d) using the on-farm available variables energy-corrected milk yield and body weight were not markedly improved by including milk concentrations of individual milk FA in prediction equations. In conclusion, replacement of barley with oats as a concentrate supplement for dairy cows fed a grass silage-based diet could offer a practical strategy to change the FA composition of milk to be more in accordance with international dietary guidelines regarding consumption of SFA.     

Physical properties of barley and oats cultivars grown in high altitude Himalayan regions of India

In this study, some selected physical properties of oats and barley viz seed size, shape, gravimetric properties, density characteristics, angle of repose, static coefficient of friction and terminal velocity were determined at a constant moisture content of 8.0 %. These properties are often required for designing of food processing appliances. The average of the principle diameters was found to be 4.96 ± 0.50, 5.34 ± 0.31, 6.00 ± 0.26 and 5.41 ± 0.44 mm and 1,000-grain weight was 41.9 ± 0.2, 40.06 ± 0.02, 36.66 ± 0.01 and 36.51 ± 0.02 g for hulled barley, hulless barley, Sabzaar oats and SkO-20 oats, respectively. The grains were narrow and elongated having an average sphericity of 50.55 ± 3.7, 47.923 ± 1.8, 32.578 ± 1.3 and 35.69 ± 2.1 %, respectively. The physical properties of the flours like angle of repose, flowability, bulk and true density were also determined. The value of angle of repose was found to be 50.44 ± 0.27⁰, 63.45 ± 0.34⁰, 46.86 ± 0.25⁰ and 44.49 ± 0.10⁰ for the flour of hulled barley, hulless barley, oats Sabzaar and SKO-20, respectively. The flours had poor flowability having a compressibility index of 33.69 ± 0.12, 34.32 ± 0.87, 27.94 ± 1.23 and 27.5 ± 0.74 and Hausner’s ratio 1.58, 1.52, 1.38 and 1.37, respectively.     

Dietary manipulation of the yield and composition of milk: Effects of dietary inclusions of barley and oats in untreated or formaldehyde-treated forms on milk fatty acid composition

Eight 1st-lactation cows were given four dietary treatments in a duplicated 4×4 Latin square experiment. Diets consisted of hay and soya bean meal together with barley, formaldehyde-treated barley, oats or formaldehydetreated oats (approximately 34:12:54 on a dry matter basis). Barley diets supplied 211 g fatty acids d^?1, oats diets supplied 537 g d^?1. The fatty acid composition (g kg^?1 total fatty acids) for barley diets was: 300 (16:0); 20 (18:0); 150 (18:1); 470 (18:2); 60 (18:3). Corresponding values for oats diets were 180, 20, 390, 380 and 30 g kg^?1. Formaldehyde treatment of the cereals tended to increase milk yield and reduce milk fat content (P<0·01 for barley) but did not affect milk fatty acid composition. Feeding oats in replacement for barley significantly (P<0·05) increased milk yield and lactose yield and reduced milk fat content (P<0·05 for the untreated cereals) and protein contents (P<0·01) without significant effects on milk fat or protein yields. Oats diets led to significant (P<0·001) reductions in the content of 8:0–16:0 fatty acids in milk fat with associated increases (P<0·001) in the content of 18:0 and 18:1. Changes in milk fat content of 18:2 and 18:3 acids were small. The results show the inclusion of oats in the cow's diet to be a means of reducing the saturated fatty acid content of milk fat thereby improving the nutritional value of milk and milk products and their appeal to the health-conscious consumer.     

Assessment of nutritive value of cereal and legume straws based on chemical composition and in vitro digestibility

The nutritive value of 17 straws was determined on the basis of their chemical composition, in vitro dry matter (DM) digestibility and rumen fermentation kinetics (from gas production curves measured in vitro). Five roughages were from the cereal species Avena sativa (oat), Hordeum vulgare (barley), Secale cereale (rye), Triticum aestivum (wheat) and Zea mays (maize stover). The other 12 samples were legume straws, two samples from each of the species Cicer arietinum (chickpea), Lens culinaris (lentil) and Phaseolus vulgaris (bean) and one sample from each of the species Lathyrus sativus (chickling vetch), Lupinus albus (white lupin), Pisum sativum (field pea), Vicia articulata (one‐flowered vetch), Vicia ervilia (bitter vetch) and Vicia sativa (common vetch). All samples were collected after harvesting from different farms located in León (northwestern Spain). Based on their chemical composition, digestibility and gas production characteristics, species could be clustered into two groups with a significant linkage distance, one for cereal straws that merged at a level of similarity of 80% and the other for legume straws with a degree of similarity of 50%. Species varied widely and significant differences (P < 0.05) were observed between the two groups of straws. Legume straws showed higher crude protein (74 ± 6.1 vs 29 ± 2.2 g kg^?1 DM) and lower fibre (584 ± 18.1 vs 793 ± 27.5 g neutral detergent fibre kg^?1 DM) contents than cereal straws and, consequently, DM digestibility coefficients (0.670 vs 0.609; standard error of difference 0.0054) and metabolisable energy values (7.4 ± 0.15 vs 5.7 ± 0.24 MJ kg^?1 DM) were significantly greater in legume than in cereal straws. Although there were noticeable differences among species within each botanical family, legume straws showed better nutritional quality than cereal straws, indicating that they could be considered promising and interesting sources of roughage for incorporation into ruminant diets. Copyright © 2005 Society of Chemical Industry     

The apparent ileal digestibility of amino acids and the digestible energy content of naked oats (Avena sativa cv Bandicoot) fed to growing pigs

An experiment was conducted to determine the apparent ileal digestibility of amino acids and the digestible energy (DE) content of two samples of naked oats (Avena sativa cv Bandicoot) and to compare these parameters in wheat (Triticum aestivum cv Machete) and dehulled oats (groats; Avena sativa cv Echidna). Four Large White male pigs were fitted with simple T-piece ileal cannulae and allocated to experimental diets in a 4×4 Latin square design. Amino acid digestibility coefficients were determined after continuous eight hour collections of digesta over two consecutive days using acid-insoluble ash as an indigestible marker. Digestible energy was determined using grab samples of faeces. No significant difference between the four test cereals was found in the digestibility of all amino acids, except for proline and lysine. The apparent ileal digestibility of lysine in wheat (0·87) and two samples of naked oats (0·89 and 0·82, respectively) was lower (P<0·05) than dehulled oats (0·91). The mean DE value of the naked oats samples was 16·96 MJ kg⁻¹ (air-dry basis). The results suggest that Bandicoot naked oats and dehulled oats are superior amino acid and DE sources to wheat and have potential for use in weaner and grower pig diets. © 1998 SCI.     

Replacement of barley with oats and dehulled oats: Effects on milk production,enteric methane emissions,and energy utilization in dairy cows fed a grass silage-based diet

Sixteen Nordic Red dairy cows, at 80 ± 4.6 d in milk and with an average body weight of 624 ± 91.8 kg, were used in a replicated 4 × 4 Latin square design to investigate the effects of different concentrate supplements on milk production, enteric CH₄ emissions, ruminal fermentation, digestibility, and energy utilization. The cows were blocked into 4 groups based on parity and milk yield and randomly assigned to 1 of 4 experimental concentrates: (1) barley, (2) hulled oats, (3) an oat mixture consisting of hulled and dehulled oats, 50:50 on dry matter basis, and (4) dehulled oats; canola meal was a protein supplement in all 4 concentrates. The cows were fed grass silage and experimental concentrate (forage-to-concentrate ratio 60:40 on dry matter basis) ad libitum. To compare the effects of barley and oats, the barley diet was compared with the overall mean of the hulled oat, oat mixture, and dehulled oat diets. To investigate the effects of gradual replacement of hulled oats with dehulled oats, linear and quadratic contrasts were specified. Milk and energy-corrected milk (ECM) yield were higher on the oat diets compared with the barley diet but were not affected by the type of oats. Concentrations of milk constituents were not affected by grain species or type of oats, except for protein concentration, which was lower on the oat diets than on the barley diet. Feeding the oat diets led to higher milk protein yield and higher milk urea N concentrations. Feed efficiency tended to be higher on the oat diets, and linearly increased with increased inclusion of dehulled oats. Methane emissions (g/d) and CH₄ yield (g/kg of dry matter intake) were unaffected by grain species but increased linearly with increasing inclusion of dehulled oats in the diet. Because of higher ECM yield, CH₄ intensity (g/kg of ECM) was on average 5.7% lower from cows on the oat diets than on the barley diet. Ruminal fermentation was not affected by dietary treatment. Total-tract apparent digestibility of organic matter, crude protein, and neutral detergent fiber was unaffected by grain species but linearly increased with increasing inclusion of dehulled oats. Gross energy content was higher on the oat diets and linearly increased with increasing inclusion of dehulled oats. Feeding the oat diets led to a lower ratio of CH₄ energy to gross energy intake, greater milk energy and heat production but no change in energy balance. Gradual replacement of hulled oats with dehulled oats linearly increased gross energy digestibility, CH₄ energy, metabolizable energy intake, heat production, and energy balance. We observed no effect of dietary treatment on efficiency of metabolizable energy use for lactation. In conclusion, replacing barley with any type of oats increased milk and ECM yield, which led to a 5.7% decrease in CH₄ intensity. In addition, dehulling of oats before feeding is unnecessary because it did not significantly improve production performance of dairy cows in positive energy balance.     

Hull-less barley for swine: ileal and faecal digestibility of proximate nutrients,amino acids and non-starch polysaccharides

The nutritive value of three hull-less barley cultivars (Condor, Falcon and CDC Buck) were evaluated. The samples were analysed for proximate composition, amino acids and non-starch polysaccharides (NSP). Wheat and normal barley were used for comparison. Apparent digestibilities were determined with eight cannulated pigs. The diets were formulated to have all energy and protein supplied by the cereals. Compared to normal barley, hull-less barley has higher contents of protein and amino-acids, and lower levels of fibre components. The levels of several essential amino acids in hull-less barley are higher than in wheat. No obvious differences in NSP composition were observed, but the hull-less barley contained considerably higher levels of β-glucan compared to hulled barley and wheat. In digestion trials the piglets did not accept the diet in which conventional barley was formulated as the only energy and protein source, whereas hull-less barleys were well consumed. The results showed that, in the order of Condor, Falcon, CDC Buck and wheat, the overall tract digestibilities of intake energy were 83·1, 80·3, 83·2 and 82·9%, and of protein were 72·6, 69·5, 76·5 and 77·6%, respectively. The averages of apparent ileal amino acid digestibility were 56·5, 58·4, 65·3 and 65·4%, respectively. Hull-less barleys showed 20–37% ileal digestibility of total NSP. This study provides digestibility coefficients of hull-less barleys, and it is concluded that the digestibility of hull-less barley is comparable to wheat and superior to hulled barley in terms of nutrient composition and acceptability. © 1998 SCI.     

The chemical composition and true metabolisable energy content of cassava root meal imported into Northern Ireland

The chemical composition and true metabolisable energy (TME) content of 10 samples of cassava root meal imported into Northern Ireland were measured. There were no major significant differences in the chemical composition of the native and pelleted cassava. Traces of HCN were found in all the samples and the four mycotoxins for which examinations were carried out were absent. The true metabolisable energy content of the meal was 13.46 MJ kg^?1 as fed, i.e. 15.13 MJ kg^?1 in the dry matter.     

Natural levels of ethyl formate in stored grains determined using an improved method of analysis

Ethyl formate was readily determined with a gas chromatograph (GC) equipped with a flame ionisation detector. Natural levels of ethyl formate in Australian wheat, barley, oats, and canola were analysed by GC, after extraction with ammonium nitrate solution. Background levels of ethyl formate were present in newly harvested and stored grain. The levels of ethyl formate (0.1-0.6 mg kg⁻¹) in grains varied with commodity, temperature, moisture and period of storage. The values ranged from 0.1 to 0.2 mg kg⁻¹ for newly harvested wheat, barley and oats, and 0.3-0.4 mg kg⁻¹ for newly harvested canola. Ethyl formate was present in grains at harvest, increased during the first 7 months of storage, and then began to decline, particularly at grain temperatures higher than 25°C and moisture contents higher than 12.5% (for wheat, barley and oats) and 6.5% (for canola). The natural levels of ethyl formate should be considered when establishing maximum residue limits.     

TRI12 based quantitative real-time PCR assays reveal the distribution of trichothecene genotypes of F. graminearum and F. culmorum isolates in Danish small grain cereals

Quantitative real-time PCR assays, based on polymorphisms in the TRI12 gene of the trichothecene pathway, were developed to identify and quantify the trichothecene genotypes producing 3-acetyl-deoxynivalenol (3ADON), 15-acetyl-deoxynivalenol (15ADON) or nivalenol (NIV) in the Fusarium graminearum species complex, Fusarium culmorum, Fusarium cerealis and Fusarium pseudograminearum. These assays were applied on a total of 378 field samples of cereal grain of wheat, barley, triticale, rye and oats collected from 2003 to 2007 to study the trichothecene genotype composition in Danish cereals. The three genotypes, 3ADON, 15ADON and NIV were found in all five cereal species, great annual variation in the occurrence of the trichothecene genotypes was evident with considerable variation between the samples. 3ADON was the dominant genotype in barley, triticale, rye and oats while 15ADON was most dominant in wheat. The NIV genotype was found at low levels in most samples. Study of genotype composition within the Danish F. graminearum and F. culmorum population was based on principal component analysis (PCA). PCA revealed that the dominating genotype of F. graminearum in wheat is 15ADON. For barley, the PCA analysis indicated that the F. graminearum population consisted of all three genotypes, and in triticale, the F. graminearum population consisted mainly of 15ADON genotype. F. culmorum/F. cerealis showed correlation to the NIV genotype in wheat and triticale but not in barley. F. culmorum/F. cerealis also showed some correlation to 3ADON especially in wheat and triticale. Selected wheat and barley samples from 1957 to 2000 showed low amounts of F. graminearum and F. culmorum in general but with a dominance of the 3ADON genotype. 15ADON was not detected in these samples, except for very low amounts in the sample representing the years from 1997 to 2000. Detection of low amounts of the 15ADON genotype in these historical samples and the relatively high amounts of 15ADON genotype in 2003 and following years correspond well with the occurrence of F. graminearum and indicates that the 15ADON genotype was introduced along with F. graminearum around 2000. The amounts of the 3ADON and 15ADON genotypes correlated well with the total amount of DON whereas the amounts of NIV genotype correlated well with the amount of NIV in wheat and triticale but not in barley where the results indicate that Fusarium poae may also contribute to the NIV content.     

Moniliformin in Norwegian grain.

Norwegian grain samples (73 oats, 75 barley, 83 wheat) from the 2000-02 growing seasons were examined for contamination with moniliformin, and the association between the fungal metabolite and the number of kernels infected with common Fusaria was investigated. Before quantification of moniliformin using ion pairing reversed-phase high-performance liquid chromatography with diode array ultraviolet light detection, all samples were extracted using acetonitrile/water (84/16) and disposable strong anion exchange columns used for clean up. The limit of detection was 40 microg kg(-1). Moniliformin was found in 25, 32 and 76% of the barley, oats and wheat samples, respectively. The maximum concentrations of moniliformin in barley, oats and wheat were 380, 210 and 950 microg kg(-1), respectively. At the same time, the prevalence and infection level of the moniliformin-producing F. avenaceum/arthrosporioides was as high as 100 and >53% on average, respectively. Moniliformin concentrations were significantly correlated to the variables grain species, growing season and infection with F. avenaceum/arthrosporioides and F. culmorum. The survey indicates that the prevalence of moniliformin in Norwegian grain is high, especially in wheat. On the other hand, field conditions in Norway do not seem to favour contamination of grain with high levels of moniliformin.     

Beauvericin and enniatins A,A1, B and B1 in Norwegian grain: a survey

Norwegian grain samples (73 oats, 75 barley, 80 wheat) from the 2000 to 2002 growing seasons were examined for contamination with five different enniatins and the association between the found concentrations and the prevalence or infection level with several common Fusarium species investigated. Enniatin B was the fungal metabolite with the highest prevalence (100%) and the highest maximum concentration (5800 μg/kg, wheat). The maximum concentration of all five enniatins together in a single sample was 7400 μg/kg (wheat). Enniatin concentrations were correlated with several independent variables, among them grain species. Beauvericin was only sporadically detected in barley and wheat and at concentrations just above the limit of detection of 3 μg/kg, while amounts up to 120 μg/kg were found in oats. The likelihood of detecting enniatin A1 as well as the concentrations of enniatins B and B1 could be mainly related to infection with Fusarium avenaceum/arthrosporioides, and the likelihood of detecting beauvericin could be related to infection with Fusarium poae. This survey indicates that the prevalence of enniatins A1, B and B1 in Norwegian grain is high, and that enniatin B concentrations of above 1000 μg/kg are common in barley and wheat.     

Nutritional evaluation of peas for ducks

The nutritive value of four pea cultivars (AC Advantage, Carneval, CDC Mozart and Keoma) and soybean meal (SBM) was evaluated in a 102 h study with 48 male White Pekin ducks. All birds were tube‐fed 25 g of dextrose at 24 and 30 h after feed withdrawal, then 25 g of each feedstuff was tube‐fed to eight ducks at 48 and 54 h after feed withdrawal. Excreta were quantitatively collected during the next 54 h. Endogenous nitrogen, amino acids and energy per bird in the 54 h collection period were 1.06 ± 0.58 g, 0.047 ± 0.025 g and 0.098 ± 0.049 MJ respectively. There were differences (P < 0.05) in apparent amino acid digestibilities (AAAD) and true amino acid digestibilities (TAAD). On average, AAAD were 82.8, 82.0, 70.3, 82.4 and 77.7% and TAAD were 89.4, 89.2, 82.3, 89.5 and 85.3% for SBM, AC Advantage, Carneval, CDC Mozart and Keoma respectively. The nitrogen‐corrected apparent and true metabolisable energy values did not differ among the pea diets and were 13.36 ± 0.071 and 14.59 ± 0.071 MJ kg^?1 respectively. Respective values for SBM were 12.16 ± 0.16 and 13.39 ± 0.16 MJ kg^?1 and both were lower (P < 0.05) than in peas. Copyright © 2004 Society of Chemical Industry     

Effect of unmalted oats (Avena sativa L.) on the quality of high-gravity mashes and worts without or with exogenous enzyme addition

Barley malt is the preferred brewing material these days because of its high extract content and high enzyme activities. However, when substituting malted barley with oats to create a unique beer flavor and aroma, endogenous malt enzymes become the limiting factor. Therefore, the objectives of this study were to evaluate the effect of 10–40 % unmalted oats on the quality of high-gravity mashes/worts and to investigate the limitations of endogenous malt enzymes as well as the benefits of the application of industrial enzymes. The enzyme mix Ondea^® Pro was found to be particularly suitable for mashing with unmalted oats and was therefore used in the present rheological tests and laboratory-scale mashing trials. In order to gain detailed information about the biochemical processes occurring during mashing, the quality of mashes was comprehensively analyzed after each mash rest using standard methods described by Mitteleuropäische Brautechnische Analysenkommission and Lab-on-a-Chip capillary electrophoresis. Mashing with up to 40 % oats resulted in increased mash consistencies, color/pH (20 °C) values, β-glucan concentrations, wort viscosities 12.0 %, and filtration times as well as decreased FAN and extract contents. The application of Ondea^® Pro enormously increased the color of worts despite lower pH values but considerably improved the quality and processability of 30 or 40 % oat-containing mashes/worts. However, the substitution of up to 20 % barley malt with unmalted oats can easily be realized without the addition of exogenous enzymes.     

Chemical characterisation and ruminal nutrient degradability of hulled and hull-less oats

The objectives of this study were to determine the chemical and ruminal nutrient degradability characteristics of two hulled (Calibre and AC Mustang) and one hull-less (AC Belmont) oat varieties. Ruminal nutrient degradability characteristics of the oat varieties were determined relative to barley using one ruminally fistulated cow. Neutral (NDF) and acid (ADF) detergent fibre levels were higher (P < 0·05) in hulled than hull-less oats. Hulled AC Mustang had higher (P < 0·05) NDF and ADF content than hulled Calibre. Starch content was higher (P < 0·05) in AC Belmont (590 g kg⁻¹) than Calibre (457 g kg⁻¹) and was higher in Calibre than AC Mustang (415 g kg⁻¹). Crude protein was higher (P < 0·05) in hull-less than hulled oat. Both hulled varieties had similar CP content (average 124 g kg⁻¹). Estimated digestible energy value was highest (P < 0·05) for AC Belmont (16·94 MJ kg⁻¹), intermediate for Calibre (14·18 MJ kg⁻¹) and lowest for AC Mustang (13·34 MJ kg⁻¹). Ruminal dry matter and NDF degradability were higher (P < 0·05) in hull-less than barley and was higher in barley than hulled oats. Ruminal starch degradability exceeded 900 g kg⁻¹ for all tested feeds and had the order AC Belmont = barley > Calibre = AC Mustang. It was concluded that oat varieties used in this study varied considerably in their chemical composition and ruminal degradability. When compared with barley, hulled oats had lower while hull-less oats had higher ruminal degradability. © 1998 SCI.     

Dispersibility of cereal proteins in urea solutions

Protein estimations by the biuret method were highly correlated with Kjeldahl determinations for 87 samples of the seven major cereal grains. The extent of binding of acid orange 12 in a phosphate buffer at pH 1·7 was correlated with the protein content but was affected by non-specific binding which varied with the tested cereals. Extraction with 3M-urea at 4° yielded an average of 67·9% protein from wheat, 67·3% from wheat flour, 66·2% from rye, 71·2% from oats, 46·7% from barley, 32·1% from rice, 22·3% from corn, and 24·6% from sorghum. Differences in dispersible proteins seem to be affected by the disaggregating and hydrogen-bond-disrupting effect of urea, and seem to be related to amino-acid composition and functional properties of cereal proteins. The urea-dispersible protein fraction in wheat flour was higher than in whole wheat.