Journal of the Institute of Brewing

The microbiological quality of draught no- and low-alcohol beers

Giulia Roselli — 2026-03-06

Why was the work done: To determine the microbiological quality of draught no- and low-alcohol beers in the on-trade and to provide insight into the factors that may influence susceptibility to spoilage.

How was the work done: 53 samples comprising of 17 brands, seven different beer styles (lager, India pale ale, pale ale, wheat, radler, pilsner and amber ale), were sampled at least twice in 12 different public houses in Nottingham, UK. Spoilage potential was determined using a forcing test with beers incubated statically at 30°C for 96 hours. Quality was assessed – using four categories - based on the relative increase in absorbance at 660 nm, reflecting the growth of beer spoilage microorganisms present in the beer at dispense. The physiochemical properties of each beer (ethanol, present gravity, pH) were evaluated pre- and post-forcing.

What are the main findings: 54.7% of the draught beers sampled were of ‘unacceptable’ quality due to microbial growth. Additionally, the concentration of ethanol was elevated, with some samples exceeding the limit for no- and low-alcohol beers in the UK. Principal Component Analysis showed that samples ranked as ‘unacceptable’ were positively correlated with a high present gravity and high pH. However, the susceptibility of no- and low-alcohol beers to spoilage is also determined by interacting intrinsic factors (lack of ethanol and carbohydrate profile) and extrinsic influences (hygiene of dispense equipment together with the rate of beer throughput).

Why is the work important: The reduction or elimination of ethanol (an antimicrobial hurdle) in the production of no- and low-alcohol beers results in a product that is more susceptible to spoilage by microorganisms. To ensure product quality and food safety, it is recommended that no- and low-alcohol beers should have a pH < 4.0, contain minimal residual sugar content, and undergo appropriate stabilisation procedures prior to packaging. The production of ethanol by dispense microorganisms presents an additional risk to the no- and low-alcohol category. This should be considered by brewers to ensure that this does not become a compliance issue. Further, particular care should be taken in the hygienic handling of no and low products, with implementation of robust and regular cleaning regimes for conventional long line dispense systems.

The transport of new make spirits through American white oak

Taylor Scott — 2026-03-06

Why was the work done: The reduction of maturation loss is a significant opportunity for increased revenue in aged spirits and varies through several factors. This work aims to better understand maturation loss by isolating and measuring spirit flow through wood.

How was the work done: Bourbon stave disks were fabricated by computer numeric control milling and loaded into a sealed module consisting of flanges holding the stave disk over a liquid filled pipe. The modules were filled with new make spirit at 50, 62.5 or 70% ABV, with either liquid or vapour contact with the stave disk. Further, the grain angle was measured for each sample. Samples were weighed each month to measure flux through the wood, with measurement of initial and final ABV and liquid mass to differentiate between ethanol or water loss.

What are the main findings: The initial alcohol content had a statistically significant (p value ≤ 0.05) effect on spirit diffusion, with the highest initial alcohol content exhibiting a 6.9 g reduction in total mass loss over the initial alcohol content. Based on the change in alcohol content, the change in mass loss is attributed to increased water uptake. Liquid versus vapour contact showed similar monthly rates of loss of mass and a statistically significant difference in total mass loss, though the magnitude of the difference is small (5.2 g, p value = 0.049), due to increased ethanol loss with liquid contact. Grain angle had no significant effect on spirit diffusion. A predicted average annual liquid loss of 1.2 ± 0.3% was calculated for non-leakage losses from a standard bourbon barrel (200L) matured in Kentucky.

Why is the work important: While the transport of water and alcohol through solid wood has been previously observed, this is the first study to investigate the diffusion of high proof alcohol through undamaged barrel staves. Maturation loss is a complex, unavoidable, and important aspect of ageing spirits, and this work establishes a lower level for maturation loss for spirit matured in Kentucky, USA.

Behaviour of volatile aromatic compounds during distillation of cachaça in a three-body pot still

Tiago Coelho — 2026-04-29

Why was the work done: The Brazilian spirit cachaça is distilled from fermented sugarcane juice. The equipment and distillation method influence the volatilisation of aromatic compounds, which affects the chemical composition and odour quality of the spirit. Distillation in a three-body pot still increases yield and productivity, but the impact of this process on cachaça aroma has received little attention. The work reported here considers the distribution of volatile compounds during distillation of cachaça in a three-body pot still, together with the composition and odour activity values (OAV).

How was the work done: Fermented sugarcane juice was distilled in a three-body pot still and 13 volatile compounds quantified using gas chromatography with flame ionisation detection and gas chromatography–mass spectrometry. The OAV of the compounds in the heart fraction of cachaça were calculated. The chemical and sensory quality of cachaça from a three-body pot still was compared to single and double-distilled spirit.

What are the main findings: The volatile compounds were classified as 'light', 'intermediate' and 'heavy', according to their volatility and distribution. Initially, aldehydes, esters and higher alcohols predominated, with acetic acid, ethyl carbamate and furfural cpredominant in the final fractions. Of the analysed compounds, 66% contributed to the aroma of cachaça, notably - with an OAV > 10 - ethyl acetate and 3-methyl-1-butanol.

Why is the work important: Distillation in the three-body pot produced high-quality cachaça, with chemical parameters within the limits of the Brazilian legislation. These results provide a reference for evaluating the quality of cachaça and for research of the odour activity values in distilled beverages.

Discrimination of stored and aged cachaça using synchronous fluorescence spectroscopy and supervised classification

Amanda Lemes Silveira — 2026-04-29

Why was the work done: Brazilian legislation requires 'aged' cachaça to be matured for a minimum of one year in wooden barrels with a maximum capacity of 700 L. 'Stored' cachaça is stored for less than a year in wooden barrels that are bigger than 700L. Discrimination between these categories is required to mitigate against economic fraud, as the maturation process increases production costs and market value. The development of robust analytical methodologies for discrimination assures labelling integrity and protects the commercial value of the spirit.

How was the work done: Synchronous fluorescence spectroscopy (SFS) was used to analyse 212 samples of cachaça that were either aged or stored in barrels made of oak, umburana, bálsamo, jequitibá, and amendoim. To differentiate the two classes, supervised classification models based on partial least squares discriminant analysis were developed. Savitzky–Golay smoothing with the first derivative was used to preprocess the spectral data before splitting them into two datasets: a training set (141 samples) and a test set (71 samples) for respectively building and then validating the model.

What are the main findings: Using synchronous fluorescence spectra recorded at a Δλ (λ_em - λ_exc) of 30 nm, the model differentiated 88% of the cachaça samples as either stored or aged.

Why is the work important: The method is simple, fast and inexpensive. It establishes a robust analytical methodology to differentiate aged and stored cachaça. This study enables the validation of cachaça, providing regulatory agencies with a tool for authentication and quality control.

Reflections

David Quain — 2026-04-29

As is the way in the first issue of the year, there is a big thank you to the kind folks who took the time to review manuscripts in 2025. This celebrates the splendid group of peer reviewers who support and drive the publication of papers in the Journal. It’s a hackneyed expression but these people really make a difference and deserve our fulsome thanks. It is also the annual ‘numbers’ time for JIB. Pleasingly in 2025, the site ‘traffic’ continued to grow with visitors (from 143 countries) up (by 38%), views of abstracts (up 36%) and reads of pdfs (up 28%). The 14 research articles and two reviews in 2025 came from nine countries. Finally, there is an update on the KPIs that track the time for steps in the process compared with those in 2023-25.

Big thanks to all the reviewers in 2025

David Quain — 2026-04-29

In 2025, two reviews and 14 papers were published in the Journal of the Institute of Brewing. Front and centre of the process is peer review (see https://jib.cibd.org.uk/index.php/jib/article/view/86 for where ‘review’ fits in the end to end process). This is the key process in scientific publication. The review process inevitably takes a lot of time but, without doubt, results in significantly better manuscripts for the benefit of the authors, the Journal and its readers.

Accordingly, I would like to fulsomely thank the 26 busy reviewers who freely gave their time and expertise to review manuscripts for the Journal. Many will have reviewed the manuscript on submission and after revision. Further, six reviewers were kind enough to review two manuscripts with one reviewing three and another contributing a magnificent four reviews!