Development of a Novel Technique for Evaluating Beer Foam Color Using Two-Dimensional Colorimeter

Chapter 1 - Beer foam: achieving a suitable head

A suitable head on a beer is one of the first characteristics by which consumers judge the quality of their beer; thus it is of vital importance to brewers. Beer foam quality is characterized by its stability, adherence to glass, and texture, which are inherently determined by the quality of the barley and hop raw materials used for beer production. In addition, beer production processes, addition of foam palliatives, packaging and method of dispense influence the basic foam quality determined by the raw materials. Elevated levels of key malt proteins and hop acids generally influence foam quality positively, while the inclusion of excessive levels of lipids, protein modification, and ethanol generally reduce foam quality. The primary objective of this review is to identify malt components that can be manipulated to produce beer foam of superior quality.

12 - Beers

Beer foam and storage haze stability are of critical importance to brewers because they are among the first characteristics by which a consumer judges the quality of his or her beer. Key malt-derived, foam-positive proteins, including protein Z4, lipid transfer protein 1 (LTP1), and some members of the hordein storage protein family, interact principally with hop acids to stabilize foam. Silica-mediated beer stabilization procedures remove haze-active protein with high levels of proline (>30%) and glutamine (>30%), suggestive of a hordein origin, without reducing foam stability. Polyclonal antibodies to protein fractions of enriched beer foam proteins and proteins extracted from silica used for beer stabilization were developed. The antibodies were found to measure different malt-derived proteins. The antibodies were subsequently used to select foam-positive and haze-active hordein-recognizing monoclonal antibodies, which enabled the development of enzyme-linked immunosorbent assays (ELISAs). The ELISAs and immunochemical procedures were applied to predict beer foam and haze quality from malt used to brew beer by using pilot- (50 L) and small-scale (0.6–0.8 L) brewing procedures. It is anticipated that the immunochemical methods may be applied to select and manipulate malt for brewing to improve beer foam stability while reducing the likelihood of storage haze formation.

Foam quality is an important index for judging the quality of beer. In this experiment, the interaction between PZ and iso-α-acid extracted from hops and its effect on beer foam production were investigated. According to the results of fluorescence titration experiments, the stoichiometric number ratio of PZ interacting with iso-α-acid was 3.91 ± 0.39, and the binding constant K was (2.16 ± 0.23) × 105 M−1. According to the results of molecular dynamics simulations, the binding sites of iso-α-acid in PZ were Leu-396, Ser-292 and Lys-290. The secondary structure of PZ was altered by the addition of iso-α-acid, and the percentage of β-sheets increased from 21.75% to 29.74%. which increased the protein’s flexibility, leading to enhanced foaming, stability, and texture of the foam.

Many of the methods for measuring beer foam are based on measurements of the weight or volume of beer collapsed from foam rather than on measurements of the foam itself. However, these drainage methods may not reflect the consumer's perception of foam collapse. Therefore, a method to characterize numerous properties of total poured foams from fully carbonated packaged beers was developed. Visual measurements were obtained with readily available equipment. Foam collapse was found to be a complex phenomenon, however, it was found to have a useful logarithmic relationship over a 1- to 5-min period. The total foam stability of commercial beers, expressed as half-life, was typically found to be in the range of 2–5 min—a value greater than that reported for beer drainage. Foam densities at 1 min typically ranged between 0.14 and 0.24 g/ml. The half-life and density were found to increase with foam volume produced at dispense. A prototype instrument using video camera technology has been developed to measure and calculate total foam attributes.

Product image display in marketing communications plays an important role in consumer perception and behavior. In this dissertation, I explore one significant aspect of product image display, namely, the facing direction of product images. Building on the literature of visuospatial attention and spatial representation of time, this research shows that products whose images are facing toward the left (vs. right) are evaluated more favorably when consumers focus on the past, whereas the reverse holds true when consumers focus on the future. Furthermore, this research compares product facing direction with a prior established spatial cue of time, namely, product horizontal position. This research shows that when the horizontal position of product images is matched with consumers' temporal focus (i.e., left-past, right-future), products facing toward a congruent (vs. incongruent) direction with the position will receive more favorable evaluations. Further, this research shows that the effect of facing direction is stronger than the horizontal position effect. That is, product images facing toward a congruent direction (and positioned incongruently) with consumers' temporal focus result in higher product evaluations than those positioned congruently (and facing toward an incongruent direction) with consumers' temporal focus. Finally, this research demonstrates an important moderating role of product features (i.e., desirability and feasibility) in the effect of facing direction on product evaluations. That is, for products higher on feasibility features, a match (vs. mismatch) between facing direction and consumers' temporal focus leads to higher product evaluations, whereas the reverse holds true for products higher on desirability features. Important theoretical and managerial implications of this research are discussed.

The process by which man accepts or rejects food is of a multi-dimensional nature. In complex food matrices, it is not always easy to establish relationships between the individual chemical stimuli concentration, physiological perception, and consumer reaction. Consumers’ responses to food are not only based on the sensory characteristics of the product and on their physiological status but they are also related to other factors, such as previous information acquired about the product, their past experience, and their attitudes and beliefs. This paper discusses different methods to obtain information about consumer perceptions, attitudes, beliefs, and expectations.

Product image display in advertising plays an important role in consumer perception and behavior. In this research, we establish important downstream consequences of one significant aspect of product image display—facing direction—on product evaluations. Building on the literature of visuospatial attention and grounded cognition, we show that products with their images facing toward the left (versus right) in advertising are evaluated more favorably when consumers’ temporal focus is on the past, whereas the reverse holds true when consumers focus on the future. Furthermore, we establish that the impact of facing direction on product evaluations exists regardless of the horizontal position of product images. In addition, we demonstrate that for products higher on desirability features, a mismatch (versus match) between facing direction and consumers’ temporal focus leads to higher product evaluations, whereas the reverse holds true for products higher on feasibility features. Important implications for advertising theory and practice are discussed.

Apple juice is widely consumed across global beverage markets. Its colour and cloudy appearance play a crucial role in consumer perception. Various physical treatments are available to modify juice turbidity and preserve colour, among which filtration and high-pressure homogenisation are considered the most respectful to the raw juice composition. In this study, red apple juice from the Kissabel® Rouge cultivar was filtered using membranes ranging from 100.0 to 0.2 μm and homogenised at pressures from 20 to 60 MPa. The physicochemical properties were then evaluated after 205 days of storage at two different temperatures. Microfiltration (<5.0 μm) increased juice lightness (87 vs. 66), but compromised cloud and colour stability by reducing cloudiness by 15 days compared with the unfiltered juices. Homogenisation increased turbidity, both in absolute value and during storage, which is typically appreciated in 100% apple juices. Finally, colloidal stability was affected by both treatments; combining mild filtration with low homogenisation pressure yielded the highest colloidal repulsion (−16.3 mV). Elevated storage temperatures generally diminished juice quality in terms of colour tone and intensity, and accelerated particle sedimentation.

Repurpose is becoming more popular as a circularity strategy. This circularity strategy is specifically promising in the case of furniture. One of the challenges of upscaling repurpose is the negative consumer perception of repurposed products. Studies up to date pertain to consumer perception of refurbished products and products using recycled content. In this study we investigate (1) to which extent the motives mentioned within literature play a role when it comes to consumers’ perception of repurposed furniture and (2) to what extent the visibility of past identity of repurposed furniture and storytelling play a role in consumer perception. The result indicate that aesthetic and functional quality are highly valued. Storytelling seems to be a secondary motive for customers to consider a repurposed product. We further identified three categories of repurposed furniture (i.e., visibly repurposed, non-visibly repurposed and unique look) that appeal to different consumer segments. While further research can be done into the demographic profiles, these categories can be used by designers/makers to make repurposed products that better appeal to their envisioned customer base.

In the world of marketing, packaging of products is a very vital word. No doubt, it plays a significant role in effective marketing of products, especially in the global market. In marketing, the consumer is said to be king, and as such, much effort is made to draw the attention of this king through packaging in the internal scene. Many firms have confirmed that packaging has been playing an estimable role in consumer perception and the selective retention of made in Nigeria products in the global market. Thus, this paper examines the impact of packaging made in Nigeria on products for the global market.

A majority of consumers in industrialized countries today, when surveyed, report unpleasant sensations related to the use of consumer products, despite extensive premarket testing confirming a lack of irritant effect. Called “sensitive skin,” this phenomenon’s understanding has been hampered by the diversity of sensory perceptions and signs reported and by a lack of correlation between the two. Once thought to be a “princess and the pea” cultural complaint, sensitive skin is now known to be a genuine irritant response, although cultural factors do appear to play a role in consumer perceptions. Improved testing methods are now revealing the underlying physiological mechanisms of sensitive skin, which may ultimately prove to be comprised of subgroups of exaggerated sensitivity stemming from different physiological mechanisms.

Instant research work was an attempt to fortify rice and study the pasting behavior of developed fortified treatments with the advancement in storage. Purposely pectin-based coatings were developed impregnated with FeSO4 (30 and 50 ppm) and NaFeEDTA (20 and 40 ppm) and ascertained for pasting behavior of stored grains using Rapid Visco Analyzer (RVA). It was observed that storage resulted in appreciable increase in peak viscosities from 2,352.43 ± 57.03 to 2,510.65 ± 60.73 cP at 0–90 days, respectively. Likewise, trough (1,985.00 ± 17.81 to 2,080.30 ± 18.67 cP) and final (3,996.58 ± 19.88 to 4,187.95 ± 20.84 cP) viscosities were also improved with the ingress in storage from 0 to 90 days correspondingly. Moreover, pasting temperatures were raised from 73.67°C ± 1.67°C (0 day) to 75.29°C ± 1.13°C (90 day). Conclusively, it can be termed that ageing had a visible impact on pasting behavior of rice grains that ultimately has a contemporary role in consumer perception and acceptability. Practical applications There has been an alarming increase in micronutrient deficiencies that pose serious threat to well-being of individuals. Present research is a way forward to suggest some novel fortification methods to address nutritional insecurities. Moreover, authors have attempted to relate the effects of developed coated fortified rice on pasting properties that govern mainly with the food preferences and quality for consumer. It is highly hoped that edible coatings based fortification is a way forward to address the ever-increasing rate of micronutrient deficiencies with minimum quality deterioration. Furthermore, nutrition industry is expected to flourish by the launch of such health promoting food-based commodities.

A study on the biochemical changes in pear beverages during storage was conducted in the Laboratory of the Department of Horticulture, Faculty of Agriculture, Guru Kashi University, Talwandi Sabo, Bathinda, Punjab, India, during the academic year 2024-25. Pear is widely utilized in the food processing industry, valued for its naturally appealing pulp colour, which significantly enhances the visual attractiveness of food products. Colour is a critical quality attribute in processed foods, playing a key role in consumer perception and marketability. In the present study, various quantities of pomegranate seeds were incorporated to naturally colour beverages prepared from white-fleshed pear, concentrating on Ready-to-Serve (RTS) beverages and squash. The results indicated that the use of 80 gm of pomegranate seeds per litre was optimal for achieving desirable colour in both RTS and squash formulations.