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综述了主要啤酒风味老化物质是5-羟甲基糠醛(5-HMF)与反-2-任烯醛的来源、检测方法.以及啤酒生产过程中控制其含量的措施。 相似文献
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In this study, the importance of iron and copper ions and their radical formation via the respective Fenton and Haber‐Weiss reactions was confirmed. Of the other heavy metals present in the brewing process in relevant concentrations, the impact of manganese ions on beer flavour stability has been elucidated. In contrast to iron and copper, manganese ions are not removed from wort or beer to any great extent during the process. Additionally, manganese shows a similar radical‐promoting effect to that seen with iron and copper. Its reactivity, and typically higher concentration than the other two metals in beer, appear to make manganese an especially potent pro‐oxidant in beer. The results of the investigation clearly indicate that there are other heavy metals influencing the stale flavour characteristics of beer, in addition to the well‐known metals, iron and copper. In contrast to the aforementioned ions, manganese does not enter the product by being leached out of a tank or from piping materials, but rather comes from the cereals employed in brewing. This finding, concerning the importance of manganese as a redox system in beer staling, can serve as a basis for a different approach in the choice of raw materials. 相似文献
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Pilot‐scale brewing trials of a 12°P pale lager beer were conducted to look at the effect of a modified dose of hop and malt polyphenols on haze, flavour quality, and stability. Results confirmed that malt polyphenols, and particularly hop polyphenols, in the course of wort boiling, improved reducing activity values and the carbonyl content in fresh and stored beers. Hop polyphenols significantly increased reducing activity and decreased the formation of carbonyls (TBA value) in fresh and stored beer. Reduced content of malt polyphenols, combined with the use of hop CO2 extract, caused an increase in the TBA value in beer. PVPP stabilized beers tended to be lower in reducing activity. Both malt and hop polyphenols affected the intensity of “harsh taste” in fresh beers and a significant influence from PVPP stabilization of beer was not observed. The staling degree of forced‐aged beers depended on the polyphenol content in the brewhouse. Both hop and malt polyphenols had a positive impact on flavour stability. PVPP treatment of beer had a positive effect on the flavour stability of heat‐aged beers. Polyphenols, especially hop polyphenols, slowed down flavour deterioration during the nine month storage period, but the primary effect was seen during the first four months of storage. Storage trials did not show any unambiguous effects for PVPP stabilization on beer flavour stability. Results confirmed the negative impact of malt and hop polyphenols on haze stability, and PVPP stabilization minimized differences in shelf life prediction values between beers prepared with the modified dose of polyphenols. 相似文献
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Sophie Noël Nadine Metais Sabine Bonte Etienne Bodart Fabrice Peladan Stphane Dupire Sonia Collin 《Journal of the Institute of Brewing》1999,105(5):269-274
To appraise the incidence of oxygen in bottled beer, the stable nonradioactive oxygen isotope 18O2 was injected into the headspace just before ageing and subsequently analysed by proton bombardment and isotopic mass spectroscopy of all the most interesting beer fractions. Although oxygen did cause considerable oxidation of sulphites, polyphenols, and isohumulones, it was not incorporated into the carbonyl fraction, indicating that the cardboard flavour in beer is not due to lipid oxidation but to wort preparation. Nonenal potential measurement was found to be a good indicator of beer flavour staling. The impact of beer stabilisation treatments (addition of polyvinyl pyrolidone powder, potassium metabisulphite, ascorbic acid) was also investigated. 相似文献
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Hirotaka Kaneda Yukinobu Kano Minoru Kamimura Shunro Kawaskishi Toshihiko Osawa 《Journal of the Institute of Brewing》1991,97(2):105-109
The chemiluninescence (CL) analysis has been used to study beer staling. Several types of commercial Japanese beers were stored at 37°C and their CL development analysed at 60°C. The CL level in beer developed as the beer was stored to reach a maximum level and then decreased. The sum of the CL intensities for the first 1 hour showed a good relationship with staling degree as assessed in mean panel scores. It is postulated that the deterioration rates of beers might be assessed from the CL producing patterns in the fresh beers before storage. The presence of sulfite in beer depressed the CL production during its storage indicating that there is some contribution of sulfite to flavour stability due to its inhibitory effect on radical reactions in beer. 相似文献
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麦汁煮沸是啤酒生产的一个重要环节,煮沸过程影响着啤酒内味老化前驱物质的形成。避免过高的热负荷、隔氧煮沸、有效去除麦汁固形物等方法,可以减少麦汁中的羰基化合物的含量,从而提高啤酒的风味稳定性。 相似文献
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Contribution of staling compounds to the aged flavour of lager beer by studying their flavour thresholds 总被引:3,自引:0,他引:3
Daan Saison David P. De SchutterBregt Uyttenhove Filip DelvauxFreddy R. Delvaux 《Food chemistry》2009
The effect of 26 staling compounds on the aged flavour of a Belgian lager beer was studied. Strikingly, thresholds were regularly found to be substantially lower than those previously reported, and it appeared important to consider threshold values as indicative rather than absolute because of very large variations in sensitivity of individuals. In addition, a masking effect of isoamyl acetate and various interactions were observed between flavour compounds, which can considerably influence their flavour activity, even at sub-threshold concentrations. Cardboard flavour was essentially caused by (E)-2-nonenal. Additionally, methional, 3-methylbutanal, 2-furfuryl ethyl ether, β-damascenone and acetaldehyde were confirmed as key contributors to the aged flavour and to a lesser extent, (E,E)-2,4-decadienal, phenylacetaldehyde, 2-methylpropanal, diacetyl and 5-hydroxymethyfurfural. Finally, the addition of a selection of compounds could fairly well reproduce the flavour of aged lager beer, indicating that these compounds account for the major part of this flavour. 相似文献
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Pavel Čejka 《Journal of the Institute of Brewing》2011,117(1):47-54
Improving beer flavour stability is an important brewing goal. Pilot scale brewing trials (50 L) were performed that focused on the determination of the influence of hop pellet dosage and dosage timing on carbonyl compounds in stored beer. The reducing activity of experimental worts, beers and stored beers appeared to depend on the hop pellet dose. Brews with lower amounts of hop antioxidants showed an enhanced formation of carbonyl compounds over the course of beer storage. A correlation between DPPH reducing activity and the content of some carbonyls, including the important markers 2‐furfural and (E)‐2‐nonenal, was found. Fresh and aged beers hopped by different amounts of hop pellet doses were clearly distinguishable according to their carbonyl content using Cluster analysis. Results of the sensorial analysis corresponded to the analytical criteria values. Results of this study bring further evidence of the indispensable impact of hop antioxidants on the suppression of undesirable carbonyl compound formation in the course of beer staling, which can be significant in beers hopped by aroma hops. However, hop antioxidants are only one of many factors affecting beer staling. 相似文献
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《Food quality and preference》2005,16(2):157-162
Brewers need to know how ageing affects the organoleptic properties of beer. This paper describes sensory assessments of aroma changes in lager beer subjected to accelerated staling (5 days at 40 °C) at different pH values (4.2 and 4.6), according to a new method for training panellists, based on AEDA results. It shows, for 10 key compounds whose concentrations are known to increase during staling, how modifications in pH affect ageing and perception thereof.In agreement with the AEDA results, “dimethyltrisulphide”-, “trans-2-nonenal”- and “methional”-like perceptions increased significantly as a result of ageing in regular pH 4.2 lager beers. A higher pH led to a smaller age-related intensity increase in the “cardboard” note (“trans-2-nonenal”-like). It also enhanced the “coconut” character (“γ-nonalactone”-like) but did not change the age-related intensification of the “cabbage” note (“dimethyltrisulphide”-like). Perception of the remaining six compounds (“furaneol”-, “ethyl butyrate”-, “2-methoxypyrazine”-, “acetylpyrazine”-, “β-damascenone”- and “ethyl cinnamate”-like) did not evolve with ageing or pH. 相似文献
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José Ricardo Carneiro Luis Ferreira Guido Paulo José Almeida José António Rodrigues & Aquiles Araújo Barros 《International Journal of Food Science & Technology》2006,41(5):545-552
2‐Furaldehyde is often used as an analytical indicator of beer flavour deterioration. Although 2‐furaldehyde itself has a flavour threshold far above levels generally present in beer, it can be used as a good marker of heat damage of beer. A reversed‐phase liquid chromatographic assay, using ultraviolet‐visible detection, was applied to investigate the behaviour of 2‐furaldehyde throughout the brewing process and during extended storage of beer. The impact of storage temperature, sulphur dioxide and oxygen content on the level of 2‐furaldehyde was studied. It was found that the concentration of 2‐furaldehyde markedly increases during wort boiling and is rapidly reduced by yeast during the first hours of fermentation, emphasising the yeast reducing capacity as a determinant factor for the 2‐furaldehyde content found in the final beer. The results obtained suggest that sulphur dioxide and oxygen content play a key role on the 2‐furaldehyde content in packaged beer. 2‐Furaldehyde increase during ageing is oxygen dependent and sulphur dioxide retards its development by possibly protecting beer against the occurrence of oxidative reactions. 相似文献
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Elke K. Arendt 《Journal of the Institute of Brewing》2011,117(3):411-421
Oats are a cereal with beneficial nutritional properties and also unrealized brewing potential. Furthermore, oats can be tolerated by the majority of people who suffer from celiac disease. Malting of oats produced a malt, which was found suitable for brewing a 100% oat malt beer. The mashing regime, designed by using mathematical modelling, was successfully transferred to a pilot scale plant. The improved lautering performance of oat malt was due to its higher husk content, which also led to a lower extract content in oat wort when compared to barley wort. The protein profile of oat wort, as measured by using Lab‐on‐a‐Chip analysis, revealed that there was no significant difference in the protein profile between oat and barley wort. The fermentation of oat and barley worts followed the same trend; differences could only be seen in the higher pH and lower alcohol content of the oat beer. The flavour analysis of oat beer revealed some special characteristics such as a strong berry flavour and a lower amount of staling compounds when forced aged. This study revealed that it was possible to brew a 100% oat malt beer and that the produced beer was comparable to a barley malt beer. 相似文献
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Jessika De Clippeleer Gert De Rouck Luc De Cooman Guido Aerts 《Journal of the Institute of Brewing》2010,116(4):381-398
In this paper, the involvement of iso‐α‐acids in the appearance of stale flavour in beer during storage was examined. Flavour instability upon storage, by far the most important quality problem of beer, may be caused by a multitude of reactions, in particular, the degradation of trans‐iso‐α‐acids is pivotal. In order to gain improved understanding of the beer ageing process, the behaviour of the stereoisomers of the bitter acids was studied for the first time in pilot beers at particularly high and low proportions of the trans‐iso‐α‐acids concentration relative to the cis‐iso‐α‐acids concentration. Therefore, pure trans‐ respectively cis‐isomers were required and obtained on a pilot scale by the separation of trans‐iso‐α‐acids as β‐cyclodextrin inclusion complexes from a commercial isomerised hop extract, permitting the quantitative dosage to beer in mg/L amounts. The relationship between the storage‐induced degradation of these iso‐α‐acids in authentic beer samples and the increase in staling aldehydes, especially 2‐methylpropanal, 2‐methylbutanal and 3‐methylbutanal, is the subject of further investigations. A remarkable increase in the relative concentration of cis‐iso‐α‐acids was observed in the beers bittered with purified trans‐iso‐α‐acids, which may be ascribed to partial conversion, i.e., reverse isomerisation, of trans‐iso‐α‐acids via α‐acids into cis‐iso‐α‐acids. In spite of the trans‐specific degradation observed during ageing, the decomposition of these bitter acids leading to volatile carbonyl compounds is of minor importance. Aldehyde formation as a function of forced ageing was irrespective of the mode of bittering, emphasising that malt quality and the brewing process itself are probably the most important factors regarding the flavour instability of beer. 相似文献