Seed Vigour In Relation To Heat Sensitivity And Heat Resistance In Barley Evaluated By Multivariate Data Analysis

The vigour loss model based on normal distribution after artificially ageing by heat treatment of barley seeds developed by Ellis and Roberts and further developed at Carlsberg by Aastrup et al. introducing vigour potential (VP), does not adequately describe seed vigour for all barley samples. In a preliminary investigation we have identified heat‐resistant barley samples. In this investigation we found untreated barley samples from the field where heat treatment as high as 68°C for 4 h at 12% water content only decreases germination from 99.0% to 93.8% compared with 94.8% to 0.0% for some of the heat‐sensitive barleys following the above mentioned model. The correlation between germination velocity measured by the germination index (GI) of untreated samples and VP is not consistent when comparing different barley material. It is concluded that the classic vigour loss model for heat treatment may be used as a worst case prediction for germination, but it does not address the variation found in practice, including the possible advantage of exploiting the naturally occurring heat resistance.     

Near Infrared Transmission Spectra of Barley of Malting Grade Represent a Physical‐Chemical Fingerprint of the Sample That Is Able to Predict Germinative Vigour in a Multivariate Data Evaluation Model

The physiological and physical‐chemical basis of barley germination was studied. Vigour was defined as germination percentage after 24 h and viability as that of 72 h. The barley samples were analysed under germination capacity and energy conditions after harvest and after long time cold storage at 7°C three‐six years. These parameters were each correlated by Partial Least Squares Regression (PLSR) to two separate multivariate data sets: a set of ten physical‐chemical parameters and to Near Infrared Transmission (NIT) spectra (850–1050 nm). Surprisingly high correlation coefficients for each of these two data sets were obtained especially with vigour, extract (%) and β‐glucan in wort (mg/L) when outliers with viability below 92% were removed. Hard, slowly germinating seeds were more resistant to decay in vigour and viability storage than soft seeds. This change could be predicted by PLSR correlations to the two physical‐chemical multivariate methods. Vigour was a more sensitive indicator for the ability to store than viability. The steep criterion was also found to have a physical‐chemical basis. The results indicate that NIT calibrations can be used to predict vigour in malting grade barley.     

The Influence of Barley Storage on Respiration and Glucose‐6‐Phosphate Dehydrogenase During Malting

Malt is produced by the controlled, but limited germination of barley. To produce good quality malt, the barley employed must be able to germinate rapidly and synchronously. Dormancy is a seed characteristic that can interfere with the rapid and uniform germination of barley, thereby reducing the resultant malt quality. Various studies have shown that post harvest storage can be used to remove dormancy and enhance barley germination characteristics and malt quality. Because of its complexity, the fundamental basis of dormancy induction, maintenance and termination remain unknown. Glucose‐6‐phosphate dehydrogenase (G6PDH) is the rate limiting enzyme of the pentose phosphate pathway and has been associated with dormancy decay and increased seed vigor of a variety of different seeds. The aim of this study was to determine if changes in barley germination vigour were associated with respiration and/or G6PDH changes during malting. Commercially grown barley (cv. Gairdner) was obtained from various states of Australia and stored at room temperature for up to 7 months. At 1, 3 and 7 months, samples were taken and stored at ?18°C. The germinative energy (GE) and germinative index (GI) of these samples were measured. Samples were micro‐malted and the α‐amylase activity, respiration rate, and G6PDH activity of the germinating grains were measured at various stages of malting. It was found that storage of barley for up to seven months significantly improved the germination characteristics and increased the α‐amylase activity during malting. However, these improvements were not associated with concomitant changes in respiration rate or G6PDH activity during malting.     

A New Germinative Classification Model of Barley for Prediction of Malt Quality Amplified by a Near Infrared Transmission Spectroscopy Calibration for Vigour “On Line” Both Implemented by Multivariate Data Analysis

A new germinative two‐dimensional classification plot fully compatible to the current EBC analyses (EBC methods 3.5–3.7) is proposed for malting barley based on separate estimates for “vigour” (24 h germination) as abscissa with limits at 70% and 30% and for “viability” (72 h germination) as ordinate with limits at 98% and 92%. Early detection of germination by image analysis was improved by utilising the auto fluorescence of the root cap. The seven hierarchical germinative classes visualise the quality differences in a consistent way, ordering classes according to falling extract % and increasing wort β‐glucan (mg/L). It was surprising to discover that significant barley Near Infrared Transmission (NIT) spectroscopy based Partial Least Squares Regression prediction models for “vigour” and “viability” were obtained after removing the PLSR outliers. The majority of these were found to be low in vigour. It was concluded after experimental validation that the physical‐chemical structure of the seed, reflected by the correlation of the barley NIT spectral fingerprints to germination speed, is connected to the availability of substrate for germ growth. This is another aspect of the speed of malt modification. An automated combination instrument for measuring physical‐chemical and seed germination parameters is suggested for quality control and to establish an on‐line NIT calibration network for integrated germinative and malting quality classification.     

PRE-GERMINATION IN BARLEY

Small proportions of grains of barley showing premature germination (pre-germination) were found in newly-harvested samples of good quality dormant barleys. Investigations into the cause suggested that pre-germination could result from a mechanical failure of the pericarp-testa when the moisture content of the developing grain was as high as 45%. Unsuspected pre-germination was shown to occur in samples of top quality British and Candian malting barleys.     

Changes in Germination and Malting Quality During Storage of Barley

To increase brewing yield and efficiency, malts with high extract values, high enzymic activities and good modification are essential. To produce malt that meets these requirements, the barley employed must have minimal post‐harvest dormancy and be able to germinate vigorously. The aims of this study were to determine the extent to which some Australian barley varieties changed during post‐harvest storage, how these changes influenced germination characteristics, enzyme production and malt quality, and, of the germination tests examined, which gave the best indication of a barley's malting potential. Four commercially grown barley samples were obtained, one from Tasmania and three from Victoria. Each sample was stored at room temperature for one year. At monthly intervals, samples were taken and placed at ?18°C. The germinative energy (GE) and germinative index (GI) of these samples were measured. Samples were also micro‐malted and the quality of the malt was assessed using standard EBC methodology. Storage at room temperature positively influenced the germination characteristics of all samples, with concomitant improvements in hydrolytic enzyme production during malting and in a number of malt quality parameters. It was found that, of the germination tests examined, the GI consistently correlated with enzyme activities during malting and with various malt quality parameters thus indicating that the GI is a good indicator of malting potential.     

Malting Performance of Normal Huskless and Acid‐Dehusked Barley Samples

Sulphuric acid dehusked barley had a higher germinative energy and lower microbial infection than normal huskless (naked) barley, suggesting that the pericarp layer harboured microbial infection which may have limited the germination rate. Dehusking the normal huskless barley using sulphuric acid resulted in lower microbial infection, and increased germinative energy. The normal huskless barley sample had a higher β‐glucan content than the acid‐dehusked barley and had slower β‐glucan breakdown during malting. This resulted in the release of seven times more β‐glucan during mashing, and the production of wort of higher viscosity. The normal huskless barley sample had a higher total nitrogen content than the acid‐dehusked barley but both samples produced similar levels of amylolytic (α‐ and β‐amylase) activity over the same malting period. No direct correlation was found between barley total nitrogen level and the amylolytic activity of the malt. When barley loses its husk at harvest, the embryo is exposed and may be damaged. This may result in uneven germination which can reduce malting performance and hence malt quality.     

Malting Behaviour of Barleys Grown in Canada and Spain as Related to Hordein and Enzyme Content

To continue our effort to analyse the genetic (varietal) and environmental (sites and years) effects on malting quality of barley, we have field‐tested four barley varieties, two‐ and six‐rowed, European and North American, in Spain and Canada in 1998 and 1999. The Spanish trials were autumn‐sown whereas the Canadian ones were spring‐sown. Barley grain was analysed for total protein and hordein contents and micromalted. Canadian‐grown barleys had significantly lower contents of grain protein and all‐three hordein fractions than the Spanish ones. They also had lower malt respiratory losses, wort β‐glucan and viscosity but lower fine‐ and coarse‐ground malt extract yield, friability, free amino nitrogen, Kolbach index, α‐amylase and diastatic power. In other words, the Canadian‐grown barleys, despite showing lower protein and hordein contents, produced malt of inferior quality than their Spanish counterparts, which, overall, produced higher quantities of degrading enzymes (amylolytic, proteolytic and cytolytic) during germination, thus being able to attain higher extract yield levels.     

A Reappraisal of the Differences Between Scandinavian and Spanish Barleys: Effect of β‐Glucan Content and Degradation on Malt Extract Yield in the cv. Scarlett

Forty one samples of the malting barley cultivar Scarlett were collected from both Scandinavia (15 from Finland and 10 from Denmark) and the Iberian Peninsula (15 from Spain and 1 from Portugal), during the harvest years of 1998 and 1999. These samples were subjected to grain analyses, comprising protein content, hordein fractions by high performance liquid chromatography (HPLC) and β‐glucan content. The samples were micro‐malted and the malts were analysed to determine different patterns in the influence of grain composition on malt extract development linked to the two contrasting environments. The most obvious difference found between the Scandinavian and Iberian barleys was the effect of the total and insoluble barley β‐glucans. They were an effective barrier of malt extract in the North, but appeared to increase extract in the South. A conclusion was that the positive effect of β‐glucans in the Iberian barleys was a consequence of their greater capacity to synthesise and release β‐glucan hydrolases during germination.     

采用RAPD-毛细管芯片电泳法鉴定啤酒大麦品系

我国啤酒大麦主要依赖进口,建立快速准确的进口啤酒大麦品系鉴定方法对保护我国啤酒制造业利益,维护国际贸易公平具有重要意义。该实验采用RAPD和2100毛细管芯片电泳技术,建立了我国主要进口啤酒大麦品系鉴定方法。采用毛细管芯片电泳技术对11次重复实验数据进行统计分析,根据谱带重现性、特异性筛选标志带,根据标志带精确长度和相对量确定判别标准。5条随机引物产生的7条标志带将19个啤酒大麦品种分成13组。     

制麦过程中微生物菌群的变化

通过培养计数法研究制麦过程中微生物菌群的数量变化.结果表明:大麦表面及内部微生物数量和大麦品种有关,制麦过程中的微生物主要来自大麦表面;浸麦激活污染微生物生长,发芽后期其数量达到最大值,干燥后污染微生物急剧下降;两次浸麦阶段有不同微生物菌群分布;分离及鉴定10种制麦过程中主要真菌;适当的物理和化学方法可以减少微生物数量...     

BARLEY MATURITY AND THE EFFECTS OF STEEP AERATION ON MALTING

Micromalting experiments were carried out with barleys varying in maturity. During steeping, which included water changes, the barleys were either allowed to remain static (the controls) or were mixed at intervals or were mixed continuously in continuously aerated water. No significant improvement in the uniformity of endosperm hydration, relative to controls, was found where grains had been mixed or were continuously aerated during steeping. Mature barley responded to continuous aeration with rapid germination during the steeping process, resulting in high malting losses. Periodic mixing during steeping had little effect on malt quality. It is suggested that, where air-rests are provided and mixing is not required to alleviate pressure, aeration (air-sparging) may be of no benefit when malting mature barley. Water-sensitivity was partially overcome by constant aeration, although periodic mixing was ineffective, hence aeration may be useful in malting water-sensitive barleys. The use of intermittent or continuous aeration inhibited the germination of undried dormant barleys. It is suggested that this effect was due to the excessive proliferation of microorganisms where aeration and mixing were provided.     

采用PCR-RAPD技术鉴定16种北美啤酒大麦

本文采用PCR—RAPD技术，从浸泡过的成熟胚乳中提取DNA，成功地鉴定了在北美种植的五种二棱啤酒大麦和十一种六棱啤酒大麦。与从叶芽中提取DNA的结果比较，表明该方法简单快捷而又准确可靠。     

澳大利亚麦芽大麦和加拿大麦芽大麦品质比较研究

对１９９６～１９９８年度上海口岸进口的澳大利亚麦芽大麦和加拿大麦芽大麦的品质项目逐一进行了比较分析。研究表明,澳大利亚麦芽大麦的发芽率,容重,千粒重,饱满粒含量较高,加拿大麦芽大麦的蛋白质,水分,瘦小粒,杂质含量较高。     

Control of Superoxide Dismutase Activity during Malting Using Plackett‐Burman and Box‐Behnken Experimental Design and Its Effect on Reducing Power of Wort

The Plackett‐Burman multifactorial design was employed to screen the important malting parameters for superoxide dismutase (SOD) in final malt of Ganpi‐3. The eight factors screened for SOD were steeping temperature, steeping time, peroxide hydrogen concentration in steeping water, germination temperature, germination time, withering temperature, drying temperature and kilning temperature. Variance analysis showed that steeping time, germination temperature and kilning temperature were significant for SOD activity. Box‐Behnken experimental design was further used to optimize the levels of the above three factors. By response surface methodology and canonical analysis, the optimal malting factors for higher SOD activity in final malt were: steeping time 42.2 h, germination temperature 16.9°C and kilning temperature 82.9°C. Under these conditions, the model predicted a SOD activity of 2234 U/g of dry weight malt. Verification of the optimization showed that a SOD activity of 2220 U/g was observed under optimal conditions. It showed that the experimental data could be reliably predicted by the polynomial model. Besides Ganpi‐3, three other barley varieties including Ganpi‐4, Ken‐2 and Hamelin were malted under optimal and common conditions under laboratory conditions. To some extent, SOD activities were higher in malts from the optimal malting process than those from the common malting process. Especially, SOD activities in Ganpi‐3 and Hamelin increased by 18.8% and 15.3%, respectively. Furthermore, twenty‐nine samples of malts, including eleven imported malts and eighteen domestic malts, were used. Relationships between SOD activity in malt and the reducing power of wort were examined. There was significant correlation between SOD activity and the reducing power of wort (R² = 0.8069).     

浅谈塔式制麦

将传统平面流程改为立体流程是塔式制麦的划时代革新.制麦工序的所有工艺设备均安装于园形立体制麦塔中.精选分级后的大麦一次提升至塔顶,自上而下完成浸麦、发芽、干燥全过程;由于采用了纵向立体流程,工序间以自重缓冲的方式进行物料转移.这在节省输送设备的同时避免了因物料碰撞、摩擦产生的机械损伤,提高麦芽的质量和麦芽的制成率;这样庞大的制麦系统井然有序地排布在制麦塔中,提高了空间利用率,大大节省了占地面积;设备系统高度集约化的布置,为自动控制和工艺操作提供了极其便捷的条件.塔式制麦系统的流程设计最大限度地吻合了大麦生长代谢和麦芽转化规律,设备配置使工艺阶段性得到了更精细的划分,为实施过程控制奠定了基础;以计算机为主体的可编程逻辑控制系统,使制麦参数得以精确控制,为制麦工艺的准确执行提供了可靠保证,有利于麦芽品质的稳定和提高.并详细介绍了塔式制麦的优点,以及垦3大麦,在塔式制麦中的应用.     

Mechanisms of Malt Extract Development in Barleys from Different European Regions: II. Effect of Barley Hordein Fractions on Malt Extract Yield

To examine environmental differences between southern and northern European malting barleys, particularly relating to protein and hordein influences on malt extract development, samples of the malting barley cultivar Alexis, from the Nordic countries and from the Iberian Peninsula, were used. Fractionation of hordeins was carried out on barley grams, prior to micromalting and malt analyses, using high performance liquid chromatography (HPLC). Different mechanisms for extract development, in malting barleys from the North and South of Europe, have been demonstrated. Barley protein content determined a significantly greater decrease in malt extract in the Nordic samples, compared with those from the Iberian Peninsula, while apparent final attenuation showed a more pronounced positive association with extract in the South than in the North. B‐hordein was associated with a significanlty greater decrease in malt extract in the Nordic compared to the Mediterranean samples.     

RELATIONSHIPS BETWEEN PEARLING RESISTANCES OF BARLEYS AND THE EXTRACT POTENTIAL OF THE SUBSEQUENT MALTS

A modified pearling instrument was used to determine the hardness of samples of barley and the results correlated with the extracts achieved by the malts made from those barleys. The influence of variety was such that the procedure could not be applied to selection of progeny from a breeding programme. However, the method could be used to accurately predict the malting potential of samples of varieties of malting barley if the relationship for the particular variety were known.     

Production of a Novel Virus‐Resistant Barley Line Introgression to the ryml Locus with High Malting Quality Using DNA Marker Assisted Selection

The rym1 is completely resistant to the Barley yellow mosaic virus (BaYMV)‐I, ‐II, the Barley mild mosaic virus (BaMMV)‐Ka1 and ‐Na1, and is acceptably resistant to BaYMV‐III. However, in breeding programs for BaYMV resistance, rym1 was not commonly introgressed into the established cultivars. This present study introduces a novel resistant gene, rym1, to a malting barley variety, ‘Mokkei 01530’, which was bred from a cross between a donor for rym1, ‘Y4’ line and a high malting quality variety, ‘Haruna Nijo’. This paper describes the malting quality and the agronomic performance of the line. The results indicate that ‘Mokkei 01530’, carrying rym1, is completely resistant to BaYMV‐I and has an acceptable level of resistance to BaYMV‐III. In comparison with its high quality parent, ‘Haruna Nijo’, the malt produced by ‘Mokkei 01530’ had similar levels of all malting quality characteristics. Furthermore, its agronomic performance was similar to ‘Haruna Nijo’.