Implications of Temperature Abuse on Unpasteurized Beer Quality Using Organoleptic and Chemical Analyses

Abstract

Beer flavor and sensory quality are affected by storage time and temperature due to chemical breakdown and aging. This study aimed to investigate the organoleptic properties of temperature-abused, unpasteurized craft beer and analyze the chemical breakdown associated with the process. Sensory tests were performed using a triangle test to determine consumer identification of temperature-abused beer. The chemical tests were conducted to determine the chemical breakdown of the two beer groups: control beer (COB) and temperature-abused beer (TAB). The chemical analysis of the two beer groups showed significant changes in multiple chemical compounds such as ethyl esters, linear aldehydes, and sulphur-compounds; however, the sensory analysis results were not significant even though 39% of participants were able to detect differences. in this study, two factors identified that caused chemical reactions in the TABs were oxidation and live yeast cells. In conclusion, these results can be used by beer producers to ensure a quality product throughout the distribution chain by controlling time and temperature.

Increasing of craft beer shelf life, with and without alcohol, through immersion batch pasteurization

“…When calculating the pasteurization time in bottled beer, the centre of the bottle should be taken as a reference. It is necessary to consider a time both in heating and cooling; and the insulating effect of the container should not be overlooked as well [17].…”

“…An interesting topic of the pasteurization process, from an industrial point of view, is the heating and cooling of the containers during pasteurization. The mathematical models used for time calculations must take into account the thickness and materials of the container, because otherwise there will be an important difference between the pasteurization model and reality, which can make the results obtained are not the expected ones [17].…”

Brewing on an industrial and a craft scale – impact on the physicochemical properties and volatile compounds profile of the pale pilsener-style lager beer analysed with HS/GC-MS

“…pasteurisation, microfiltration) and process conditions (wort aeration level, fermentation temperature, conditioning time), yeast strain (secondary metabolites), as well as storage conditions (light and oxygen contribution) and last but not least by microbial contamination [1,[11][12][13][14]. Hence, In order to provide a highquality product, it is necessary to keep good manufacturing practice (GMP) and obtain the balance of the beer aroma through maintaining a proper concentration of volatiles such as esters, higher alcohols, carbonyl compounds (aldehydes and ketones), sulphur compounds and organic acids, which at concentrations above their sensory thresholds are perceived either detrimental or beneficial to beer flavour depending on its style [4,14]. In this way, the volatile profile is one of the unique characteristics of each beer style, determining its quality [15].…”

“…In the analysed batch of samples a total of 57 volatile compounds were identified by using NIST spectrum library and literature LRI values (Table 4). Those compounds can be classified into 6 groups, namely: esters (29), alcohols (14), carboxylic acids (3), carbonyl compounds (6), terpenes (4) and sulphur compounds (1). The volatile compounds profiles of 12 beers, 6 from craft group (A-F) and 6 from commercial group (G-L), are shown in Table 3.…”