ARTICLE | doi:10.20944/preprints201810.0398.v1
Subject: Chemistry, Food Chemistry Keywords: craft beer; polyphenols; bitterness; preference; sensory attributes
Online: 18 October 2018 (05:09:01 CEST)
The craft beers are outlined as a distinctively flavored, brewed and distributed regionally, using top-fermenting (ale) yeast, bottom-fermenting (lager) yeast or spontaneously fermentation. Craft beers are largely consumed and produced in Brazil and presents great level of polyphenols, which would affect the consumer’s preference. In this way, we analyzed the relation between polyphenols, bitterness and composition of main different styles of craft beers and the consumer´s preference. Six different styles were analyzed according its polyphenol content, bitterness, chemical composition, sensory profile and preference. For preference, a panel with 62 non-trained assessors was used. For sensory profile, the quantitative descriptive analysis was performed, using expert assessors (n = 8). The preferred style was Classic American Pilsner and the style less preferred was Standard American Lager. The craft beer more preferred showed a decreased bitterness (9.52), polyphenol content (0.61 mg EAG/mL), total solids (6.75 ºBrix) and turbidity (7.27 NTU). This beer exhibited reduced sensory notes of malty, fruity, smoked, hoppy and phenolic, but a higher perception of floral, sweet and yeast notes. The bitter attribute has a reduced perception. This study advances understanding the sensory profile and complexity of craft beers styles from Southern Brazilian.
ARTICLE | doi:10.20944/preprints201608.0106.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: packaging; beer; image mold; packaging weight; taste
Online: 10 August 2016 (09:04:27 CEST)
People often say that beer tastes better from a bottle than from a can. However, one can ask whether this perceived difference is reliable across consumers; And, if so, whether it is purely a psychological phenomenon (associated with the influence of packaging on taste perception), or whether instead it reflects some more mundane physico-chemical interaction between the packaging material (or packing procedure/process) and the contents. We conducted two experiments in order to address these important questions. In the main experiment, 151 participants at the 2016 Edinburgh Science Festival were served a beer in a plastic cup. The beer was either poured from a bottle or can (i.e., a between-participants experimental design was used) and the participants were encouraged to pick up the packaging in order to inspect the label before tasting the beer. The participants rated the perceived taste, quality, and freshness of the beer, as well as their likelihood of purchase, and their estimate of the price. All of the beer came from the same batch (from Barney’s Brewery in Edinburgh). Nevertheless, those who evaluated the bottled beer rated it as tasting better than those who rated the beer that had been served from a can. Having demonstrated such a perceptual difference in terms of taste, we then went on to investigate whether people would prefer one packaging format over the other when the beer from bottle and can was served to a new group of participants blind (i.e., when the participants did not know the packaging material). The participants in this control study (N = 29) were asked which beer they preferred or else could state that the two samples tasted the same. No sign of preference was obtained under such conditions. Explanations for the psychological impact of the packaging format, in terms of differences in packaging weight (between tin and glass), and/or prior associations of quality with specific packaging materials/formats (what some have chosen to call ‘image molds’) are discussed.
ARTICLE | doi:10.20944/preprints202103.0394.v1
Subject: Biology, Anatomy & Morphology Keywords: fermental traps; beer traps; Coleoptera; fauna; biodiversity; occurrence
Online: 15 March 2021 (13:56:08 CET)
The possibilities of applying various methods to study Coleoptera give unexpected and original results. The studies were carried out with the help of fermental crown traps in 2018-2020 on the territory of eight regions in the central part of European Russia. The biodiversity of Coleoptera that fall into crown traps includes 294 species from 45 families. The number of species attracted to the fermenting bait is about a third of the total number of species in the traps (this is 97.4% of the number of all caught specimens). The largest number of species that have been found in traps belong to the families Cerambycidae, Elateridae and Curculionidae. The most actively attracted species mainly belong to the families Cerambycidae, Nitidulidae and Scarabaeidae. Species of these families are equally attracted by baits made of beer, white and red wines. To identify the Coleoptera biodiversity of a particular biotope, two-year studies are sufficient, which should be carried out throughout the vegetation season. Especially good results can be obtained from studies of rare species that are actively attracted by such baits. It is possible to study the verti-cal-horizontal distribution of Coleoptera fauna in individual biotopes.
ARTICLE | doi:10.20944/preprints201608.0117.v1
Subject: Chemistry, Food Chemistry Keywords: beer; nuclear magnetic resonance; solid-phase microextraction; gas chromatography
Online: 11 August 2016 (11:04:58 CEST)
Chemical analysis of the organic components in beers has applications to quality control, authenticity and improvements to the flavor characteristics and brewing process. This study aims to show the complementary nature of two instrumental techniques which in combination can identify and quantify the majority of organic components in a beer sample. Nuclear Magnetic Resonance (NMR) was used to provide concentrations of twenty five different organic compounds including alcohols, organic acids, carbohydrates, and amino acids. Calorie content was also estimated for the samples. NMR data for ethanol concentrations were validated by comparison to a Fourier Transform Infrared Spectrometry (FTIR) method. Headspace Solid-Phase Microextraction (SPME) Gas Chromatography Mass Spectrometry (GCMS) was used to identify a range of volatile compounds such as alcohols, esters and hop derived aroma compounds. A simple and inexpensive conversion of a Gas Chromatography Flame Ionization Detector (GC FID) instrument to allow the use of Solid-Phase Microextraction was found to be useful for the quantification of volatile esters.
ARTICLE | doi:10.20944/preprints202107.0423.v1
Subject: Life Sciences, Biochemistry Keywords: non-conventional yeasts; Saccharomyces; fermentation; beer; dry-hopping; brewing potential
Online: 19 July 2021 (16:08:39 CEST)
Consumer demands for new sensory experiences have driven the research of unconventional yeasts in beer. While much research exists on the use of various common Saccharomyces cerevisiae strains as well as non-Saccharomyces yeasts, there exists a gap in knowledge regarding other non-cerevisiae Saccharomyces species in the fermentation of beer, outside that of S. pastorianus. Here, five distinct species of Saccharomyces from the UC Davis Phaff Yeast Culture Collection, as well as one interspecies hybrid from Fermentis, were chosen to ferment 40 L pilot scale beers. S. kudriavzevii, S. mikatae, S. paradoxus, S. bayanus, and S. uvarum yeasts were fermented in duplicate, with one fermenter in each pair receiving 10 g/L dry-hop during fermentation. Analytical measurements were made each day of fermentation and compared to controls of SafAle US-05 and SafLager W 34/70 for commercial brewing parameters of interest. Finished beers were also analyzed for aroma, taste, and mouthfeel to determine the flavor of each yeast as it pertains to brewing potential. All beers exhibited spicy characteristics, likely from the presence of phenols; dry-hopping increased fruit notes while also increasing perceived bitterness and astringency. All of the species in this study displayed great brewing potential, and might be an ideal addition to beer depending on a brewery’s desire to experiment with flavor and willingness to bring a new yeast into their production environment
ARTICLE | doi:10.20944/preprints201705.0054.v1
Subject: Chemistry, Electrochemistry Keywords: E-tongue; E-nose; data fusion; variable selection; patter recognition; beer
Online: 8 May 2017 (08:57:56 CEST)
Multi-sensor data fusion of E-tongue and E-nose can provide a more comprehensive and more accurate analysis results. However, it also brings some redundant information, it is a hot issue to reduce the feature dimension for pattern recognition. In this paper, the taste-olfactory data fusion based on E-tongue and E-nose combined with Support Vector Machine (SVM) was used to classify five different beers. First, the taste and olfactory feature information were obtained based on E-tongue and E-nose. Second, the original feature data of single system were fused, then Principal Component Analysis (PCA) was applied to extract principal components, Genetic Algorithm-Partial Least Squares (GA-PLS) was used to select the characteristic variables, 20 subsets were generated with those variables based on the best Variable Importance of Projection (VIP) score. Finally, the classification models based on SVM were established, also c and g of SVM were calculated by Grid Search (GS), Genetic Algorithm (GA), and Particle Swarm Optimization (PSO), the classification results of all subsets were obtained. The results showed that the classification accuracy using data fusion was much higher over single E-tongue and single E-nose, and the variable selection method by VIP had the best classification performance in #12 subset coupled with GA-SVM.
ARTICLE | doi:10.20944/preprints202105.0773.v1
Subject: Chemistry, Analytical Chemistry Keywords: Ethnic beer; borde; shamita; keribo; korefe; indigenous drinks; fermented beverages; probiotics; Farsoo; moringa
Online: 31 May 2021 (12:50:33 CEST)
This study was designed to improve Ethiopian traditional beer – tella with the substitution of gesho by moringa leaves to enhance micronutrients. Substation of gesho by moringa from 50 – 100% against the biochemical dynamics, nutritional and sensorial profiles of tella was assessed. Incorporation of moringa suppressed the activities of yeast and favored that of lactic acid bacteria, which shifted the property of the product from mild alcoholic nature to low alcoholic and mild acidic nature, revealing the probiotic potential of tella. Moringa leaves at 100% substitution for gesho resulted in to the least yeast count compared to the other formulations. The storage of tella samples over periods of 10 days also strengthened the probiotic nature of tella by drastically reducing the yeast cell counts (from 5 logs to <1). This corresponded to the slow increase in the acidity (0.63 to 0.99%), indicating comparatively higher activities of lactic acid bacteria. The best nutritional contents (dietary minerals) and sensorial acceptance of the product was attained at the 50% substitution of gesho by moringa. The implication of the present study is that ethnic foods and beverages can be innovated to meet the nutritional needs of the community