Brewing and brewing research: past,present and future

Whilst remaining largely traditional in approach, malting and brewing have become highly efficient processes through a substantial understanding of their underpinning science. Technological change in the industry is driven by four criteria: cost reduction, quality enhancement, maintenance of safety and wholesomeness and opportunity for enhanced sales. Whilst there are some opportunities for cost reductions by savings on raw materials, the major cost components in brewing involve production and packaging. Hence the focus is on energy reduction, maximising vessel utilisation and use of automated control strategies. There is scope in the future for production of beer by novel approaches, involving downstream establishment of quality parameters, though this is likely to be resisted. Quality of beer embraces both package and product. The shift towards enhanced use of non‐returnable green or clear glass has focused attention on eliminating undesirable lightstruck characters from the product as well as the use of oxygen‐scavenging crown corks to minimise the development of stale characters due to carbonyl‐containing substances. There is an increased understanding of how to control the various species that primarily determine the flavour of fresh beer, including sulphur‐containing substances, esters, higher alcohols, vicinal diketones and the bitter resin and oil fractions from hops. The achievement of stable foam on beer is dependent on the presence of foam‐stabilising components, principally amphipathic polypeptides, but is determined by the physical behaviour of bubbles, notably the phenomenon of disproportionation. Malt and beer are at risk over a range of safety issues, but all can be avoided through attention to raw material selection and processing conditions. Moderate consumption of beer is now considered to be potentially beneficial. © 2000 Society of Chemical Industry     

Consumer involvement and perceived differentiation of different kinds of pork – a Means-End Chain analysis

For firms to be able to differentiate their market offerings from those of competitors, knowledge about the consumer is essential. The Means-End Chain (MEC) approach was used to identify the consequences and values that consumers attach to product attributes. The objective of this study was to investigate the motivational structure of consumers in relation to unbranded, imported, branded and local-organically produced pork. The explanation of consumer behaviour was deepened through investigating whether consumers were more involved in some kind of labelled pork than in others. Laddering interviews with 127 consumers concerning the four kinds of pork were conducted in Swedish supermarkets. Imported pork was bought because it is cheap and was the least involving kind of pork. The most involving were branded pork and local-organically produced pork. Pork had the character of a “think” product, foremost bought for functional values. This was especially true for imported pork.     

一种检测啤酒老化的新参数

通过HPLC，研究了在啤酒贮存过程中，酒花苦味物质的变化。观察到异律草酮浓度在此过程中变化显著不同。反式异律草酮的浓度在啤酒贮存过程中逐渐减少。而顺式异律草酮的浓度没有变化。根据色谱峰面积的大小。得到反式-顺式异棒草酮的比例，该比例对于新鲜啤酒，虽然啤酒的种类不同，但总是相差不大。但对于陈酒来说，它是逐渐减少的，其减少的程度与啤酒的种类有关。同时证实了反式-顺式异律草酮的比例与啤酒陈腐味强度有相关性。反式-顺式异律草酮的比例反映了啤酒变质过程中的氧化程度。     

Influence of transport and storage conditions on beer quality and flavour stability

Breweries are exporting their brands overseas, resulting in an increasingly competitive and globalised beer market. Inevitably, the beer experiences varying and prolonged periods of transport and storage prior to consumption. During this process, the flavour of fresh beer deteriorates, leading to the presence of stale flavours and a decrease in the drinkability of the beer. Results reported here show that an increased temperature during beer transport and storage causes significant flavour deterioration, as determined analytically (increase in aldehydes, beer colour and haze formation, decrease in iso‐α‐acids concentration) and sensorially (increase in overall aging score). Further, laboratory experiments show that the vibration of beer results in a rapid decrease of oxygen. Moreover, inappropriate storage temperature has a negative effect on beer quality and stability, in particular when combined with vibration. © 2018 The Institute of Brewing & Distilling     

Linking sensory characteristics to emotions: An example using dark chocolate

The conceptual profile of an unbranded product arises via three sources of influence: (i) category effect – how consumers conceptualise the product category: (ii) sensory effect – how the sensory characteristics of a particular product differentiate it from other products in the category: (iii) liking effect – the disposition of consumers to the category and how much they like a particular product. Assuming that category effects (conceptualisation and disposition) are constant across the set of products, it is anticipated that the conceptual differences apparent across the set of unbranded products would be driven, at least in part, by sensory differences. This study describes the application of best–worst scaling to conceptual profiling of unbranded dark chocolates and outlines novel data modelling procedures used to explore sensory/conceptual relationships.     

Females' attitude and preference for beer: a conjoint analysis study

In order to sustain the fast‐expanding beer industry, companies need to attract new female consumers. The main objective of this study was to identify the extrinsic and intrinsic attributes that drive female consumers' purchase of beer. A literature review and focus group (n = 6) were conducted, and six attributes were identified as purchase drivers of beer. These attributes included flavour, appearance (colour), packaging, brand, production methods and beer style. These attributes were used to design a choice‐based conjoint analysis survey. The survey was administered to 277 females (aged 35.09 ± 15.2) residing in Nova Scotia (Canada). The results indicated that sweetness has a positive effect on liking. Bitterness has a strong negative effect on liking of beer. Black colour, stouts and macro‐brewed beers also had negative effects on liking of beer products. The consumer clusters showed that generally all of the consumer groups liked sweet beers with low bitterness.     

The Influence of Heavy Metal Ions on Beer Flavour Stability

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.     

The relationship between flavour instability,preference and drinkability of fresh and aged beer

The preference and drinkability of fresh beer compared with aged beer was tested using a ‘paired comparison test’. After a duo test with small samples, respondents could freely consume the beer of their choice. The results show that the initial preference for fresh beer was significantly higher than the preference for aged beer, with 65% of respondents taking fresh beer first after the duo test. The drinkability of fresh beer also scored significantly higher, with 35% more fresh beer consumed. However, since multiple respondents consecutively consumed multiple aged beers, it cannot be concluded that aged beer results in a lower consumption volume (per capita) when compared with fresh beer. Additionally, Belgians older than 24 years particularly favoured and consumed the fresh beer in the experiment. This was attributed to the influencing and mimicking behaviour of the other respondent groups, since the table setting and table sizes were also found to be important parameters. In this paper, we show the continuing importance of research into beer flavour stability. © 2019 The Institute of Brewing & Distilling     

Effect of UV‐C Disinfection of Beer — Sensory Analyses and Consumer Ranking

Ultraviolet (UV‐C) light irradiation is gaining rapid acceptance within the food and beverage industry as a non‐thermal disinfection technique. A series of trials, using a pilot scale UV‐C treatment system, were conducted to investigate the effect of UV‐C on beer with specific attention to lightstruck flavour formation. Both commercial and micro‐brewed beers were treated with UV‐C light at 254 nm. Samples were analysed by consumer and trained panels. Sensory analyses revealed that at a low UV‐C level, lightstruck flavour was apparent and this increasingly gave way to a more intense burnt rubber off‐flavour as the UV‐C exposure was increased. A sample enrichment probe technique coupled with a gas chromatography‐mass spectrometry (SEP/GCMS) revealed the presence of lightstruck flavour in all the treated beers.     

Effects of “craft” vs. “traditional” labels to beer consumers with different flavor preferences: A comprehensive multi-response approach

Common definitions of craft-style beers emphasize that they are brewed by small, local breweries and that they have complex, novel and, often, bold flavors. In recent research conducted with declared craft beer drinkers who tasted beers in a blind condition, Jaeger et al. (2020) [FQAP, 103884] identified the existence of two preference segments. One segment (Craft-style Likers) preferred the characteristic complex, novel and bold flavors of many craft-style beers, while the other segment (Traditional-style Likers) preferred the less complex and milder flavors associated with traditional-style beers. In the present research, a multivariate response approach that included the evaluation of liking, sensory, holistic/conceptual, and cognitive/emotional/situational responses, as well as beer-related attitudes and behaviors, was used to assess the same set of six beers in a similar sample of declared craft beer drinkers (n = 122) as used in our previous study. However, beers were now labeled to reflect the style of the beer (craft vs. traditional) and the size (small vs. large) and regional origin (local vs. international) of the brewer. Results confirmed the existence of the same two preference segments. Although the effects of labeling the beers in accordance with their craft- vs. traditional-style natures did not influence sensory, holistic/conceptual or cognitive responses, they did influence emotional and situational responses. For craft-style beer likers, the information increased their positive emotions and the situational uses for craft-style beers, while for the traditional-style beer likers the labeling had a corresponding positive effect on their judgments of the traditional style beers. The results confirm previous findings on beer and product labeling, which show that sensory properties are less susceptible to extrinsic information effects than are affective, emotional and other, non-sensory product judgments. Implications for craft and traditional brewers are discussed and suggestions for future research presented.     

INFLUENCE OF pH ON FLAVOUR STALING DURING BEER STORAGE

A decreasing pH accelerated an increase in the chemiluminescence production and degradation of isohumulones and procyanidins during the storage of beer and using a model system. The sensory test showed that the addition of HCI to fresh beer accelerated the flavour staling during beer storage but that the addition of HCI to stored beer did not significantly accelerate the flavour staling. Therefore, it was thought that the acceleration of beer flavour staling is not dependent on a decrease in pH such that the decreasing pH isolates stale flavour aldehydes by a dissociation from staling-flavour aldehyde adducts but based on the fact that the decreasing pH accelerates the flavour staling reactions, free radical reactions, during beer storage.     

Influence of information about manufacturing process on beer acceptability

The purpose of this study is to investigate the extent to which consumer information concerning the manufacturing processes of beer can influence how acceptable the product is to the consumer. In this study subjects were informed that the beer had been produced (1) using genetically modified yeast; (2) with organic barley and hops, and (3) using traditional brewing technology. Three products were selected to represent high, moderate and low acceptability. A blind evaluation of the selected samples was followed by an assessment of the subjects' expectations of the sample products based on the different information about product processing. The impact of these expectations on liking after tasting the product was examined and demonstrated that information regarding manufacturing technology is capable of modifying the consumers' liking of beer. The disconfirmation that occurred as a result of different product–information combinations revealed that liking moved towards their expectations (assimilation). However assimilation was not complete, indicating that sensory properties of products were important in determining perceived quality. Finally, the present study does not entirely confirm findings of previous research. Combining different information with different levels of product liking may lead to a better understanding of the asymmetry of disconfirmation.     

Processing of a Top Fermented Beer Brewed from 100% Buckwheat Malt with Sensory and Analytical Characterisation

A top fermented beer was brewed from 100% buckwheat malt and sensory and analytical characterisation was carried out. Difficulties with lautering and filtration were encountered during the brewing process, which resulted in problems during fermentation and beer filtration. The beer was evaluated in the fresh and forced aged state for the following attributes: odour, purity of taste, mouthfeel, tingling, and bitterness. Analytical results indicated that the buckwheat beer compared quite closely to a typical wheat beer with regard to pH, FAN, fermentability and total alcohol. However, the extract of the buckwheat wort was lower, resulting in a final extract yield of 54.5%. GC analysis of the resultant beer revealed commonly encountered levels of the esters that give beer a fruity character. A low level of fusel alcohols, in comparison to a typical wheat beer, was detected. A high level of ethyl caprinate (coconut flavour) and lauric acid (fatty odour) was detected. Sensory analysis indicated that the buckwheat beer was acceptable with regard to odour, purity of taste, mouthfeel, tingling and bitterness. In conclusion, results of this study prove buckwheat's qualification as a gluten‐free brewing material and with process optimisation, its readiness for marketing.     

Possibilities to improve the antioxidative capacity of beer by optimized hopping regimes

Different hopping regimes were evaluated to investigate the effect on the oxidative stability of wort and beer. Compared with a single hop dosage at the beginning of wort boil, it was possible to increase the concentration of α‐acids in pitching wort and beer by applying incremental hop dosage, dry hopping or the use of a pre‐isomerized hop product in combination with an α‐acid extract, which concomitantly resulted in lower iron concentrations and an enhanced flavour stability as indicated by standard wort and beer analyses, atomic absorption spectroscopy, electron spin resonance spectroscopy and sensory analysis of fresh and force‐aged beers. The functional principle of hop dosage variations is explained by saving of α‐acids throughout the wort production process, which yields an increased formation and precipitation of pro‐oxidative acting transition metal ions (e.g. Fe) in α‐acid‐complexes during the whirlpool rest and fermentation. Consequently, fewer reactive oxygen species are generated. Additional laboratory trials simulating wort cooling and beer storage in buffered model solutions proved that un‐isomerized α‐acids are strong iron chelators and confirmed the functional principle of the applied hopping regimes. Negative effects of higher α‐acid contents on fermentation performance and depletion of the zinc concentration, which is an essential nutrient for yeast, could be excluded. Copyright © 2014 The Institute of Brewing & Distilling     

Preference segments among declared craft beer drinkers: Perceptual,attitudinal and behavioral responses underlying craft-style vs. traditional-style flavor preferences

Craft beer is a product category that continues to expand, and craft beer drinkers are generally differentiated from traditional (or mainstream) beer drinkers in terms of their preference for innovative beers with novel and complex flavor profiles, and greater involvement in beer and product-focused behaviors and activities. The present research explores the existence of flavor-driven segments within the overall craft beer segment, where some declared craft beer drinkers exhibit the characteristic craft beer preference (stronger and more complex flavors), while others exhibit a preference for less complex and more traditional flavors. Research conducted with craft-style and traditional-style beers (n = 6) confirmed such preference segments in a group of male New Zealanders (n = 120). The preference segments perceived the sensory and holistic/conceptual characteristics of the beers similarly. However, they differed in specific attitudes and behaviors toward craft beers that were associated with the extent of their use and exposure to craft beers. The presence of the two preference segments was interpreted as being the result of a normal transition of declared craft beer drinker preferences away from the lighter flavors of the traditional style beers to which they had been accustomed and toward the more novel and robust flavors of craft beers. This shift in flavor preferences is tentatively attributed to the same exposure effects (mere and evaluative) that are responsible for flavor preference development in other foods and beverages. The implications for craft and traditional brewers are discussed and suggestions for future research presented.     

Personality traits and bitterness perception influence the liking and intake of pale ale style beers

Bitterness is classically considered undesirable in foods and beverages. Yet, widespread commercial success of beers (like Bitters in the UK or IPAs in the US) indicate bitterness is desirable for some consumers. Here, we tested whether personality traits influence beer liking and intake. Under laboratory conditions, beer consumers (n = 109) rated liking and intensity of 2 pale ales and a lager, and intensity of two bitter solutions (quinine, Tetralone®). Participants also completed intake and personality questionnaires (Sensation Seeking, Sensitivity to Punishment and Reward, and Food Involvement). A liking ratio for each beer was calculated from each participant’s liking for that specific beer and their total liking for all beers. Participants were classified as weekly, monthly, or yearly pale ale consumers using intake data. Using intensity ratings, personality measures, and other parameters, hierarchical linear regression was used to predict liking ratios, and logistic regression was used to predict beer intake frequency. A significant interaction between Sensation Seeking and quinine bitterness (p = 0.03) was found for the liking ratio of a pale ale. The interaction revealed liking of the pale ale increased with Sensation Seeking but only if quinine bitterness was also high. Intake models showed increased odds of frequent pale ale intake with greater quinine bitterness and lower liking for lager beer. These data suggest liking and intake of pale ales is positively related to Sensation Seeking and bitter taste perception. Contrary to findings in other bitter foods and beverages, the high bitterness found in pale ales may be desirable for some consumers.     

Does the origin of inputs and processing matter? Evidence from consumers’ valuation for craft beer

In this study we aim at exploring consumer valuation for craft beer brewed locally and made with locally grown hops. The research is motivated by the fact that, although existing literature shows that consumers generally pay a price premium for locally produced foods or those made with local ingredients, it is still unclear how consumers value localness of production (i.e., brewing location) over localness of inputs (i.e., hops origin) and whether consumers value these attributes as either complements or substitutes. Moreover, little is still known regarding consumer preference for local ingredients in beer. Thus, we address these research questions by means of a choice experiment survey on craft beer consumers in the State of Indiana, United States. Results show that consumers have the highest willingness to pay for craft beer brewed in-state, but preferences over hops origin are heterogeneous. We find evidence of complementarity between brewing and hops origins among frequent craft drinkers and evidence of substitution between these claims for casual drinkers. Segmenting consumers based on how they define local beer, we find one consumer segment that has the highest willingness to pay for beer brewed in-state and made with hops that are grown in-state. These results can inform product differentiation, marketing, and pricing strategies. They are also relevant to state policymakers supporting local hops production and local brewing.