Beer is one of the most widely consumed beverages in the world. Since the legalization of low-delta-9-tetrahydrocannabinol (THC) (<0.03%) Cannabis sativa in the United States, this controversial plant is being looked upon as a potential flavor additive for use in beer. Cannabis sativa shares similar aromatic and flavor characteristics to that of hops (Humulus lupulus). This study was designed to determine the influence ethanol concentration has on the cannabinoid and volatile compounds found in beer. Three experimental beers with varying ethanol (3, 6, and 9% ABV) concentrations were used for this experiment. Using dry-hopping practices and dosing from commercial brewing techniques, hemp was placed in the beer for five days at 25 °C. Cannabinoids and volatile compounds were analyzed following the completion of the dry-hemping process. Statistical differences were observed only for the cannabinoid, tetrahydrocannabinolic acid (THCA), while, no other individual cannabinoid or the summation of the total cannabinoids were statistically different. Volatile compounds were analyzed using gas chromatography–mass spectrometry (GC-MS). Statistical differences were observed between the monoterpenes and the sesquiterpenes volatile compound groups. In summary, ethanol concentration appears to have no impact on the extraction efficiency of cannabinoids but does appear to influence volatile compounds when hemp is added to beer through the dry-hemping process.

The exploration of space is becoming more feasible, and with this comes the possibility of performing fermentations in microgravity. Our study explores the potential effects of microgravity on a standard brewing model fermentation. As the fermentation of barley wort has been studied for centuries, there is an established foundation of knowledge with which to compare any changes that occur under microgravity. A modified ASBC miniature fermentation protocol (Yeast-14) was conducted within a Yuri 2.0 microgravity chamber to examine the response of Saccharomyces pastorianus to simulated microgravity conditions. Our findings reveal that yeast exhibited accelerated growth rates under microgravity compared to standard conditions. Additionally, the microgravity environment led to significantly lower levels of volatile compounds such as isoamyl acetate and 2-phenethyl acetate in the final product. Further genetic analysis showed significant downregulation of the ATF2 gene in the control group, potentially the mechanism behind the observed decrease in volatile compounds. These results show that while fermentation under microgravity is likely to eventually be commonplace, there may be changes in rate and gene expression that are beneficial or detrimental to the final product depending upon the desired characteristics.

Spirulina is a highly nutritious microalgae commonly used as a food additive. During fermentation, different adjuncts are incorporated to act as a nutrient source for yeast and fortify or modify the sensory attributes of the final product. In this study, the effect of Spirulina on the characteristics of controlled yeast fermentation and the production of volatile organic compounds (VOCs) was analyzed. Spirulina was added to malted barley during mashing and fermented under standard conditions. An unaltered mash (negative control) and yeast extract (positive control) were also fermented. The addition of Spirulina resulted in an increased fermentation rate (~14% faster) and bigger yeast cells (~34% larger) in comparison to the negative control. There were differences in color (determined as SRM) between treatments; however, there were only minor differences in VOCs, with no statistical differences observed between chemical compound groups. No differences were observed in the pH, total number of yeast cells, or final attenuation between treatments. The primary mechanism for the observed differences is believed to be an increase in amino acids available to yeast that were contributed by the Spirulina. This shows both that Spirulina has a high potential as a fermentation adjunct and that the amino acid profile of an adjunct can significantly impact fermentation.

Why was the work done: Diastatic variants of Saccharomyces cerevisiae are unusual in producing an extracellular glucoamylase which enables the breakdown of starch to fermentable sugars. Diastatic S. cerevisiae has long been viewed negatively as a contaminant of especially beer packaged in cans or bottles. However, this view is being reconsidered due to the opportunities that diastatic strains present for niche fermented products and distillation applications. What are the main findings: This review highlights the utilisation of diastatic S. cerevisiae for its flavour potential, and processing applications in the brewing, distilling, and biofuel industries. Further, genetic differences are compared with non-diastatic strains of S. cerevisiae, together with commonly employed and emerging methods of detection. Why is the work important: Diastatic yeast strains can be used to create flavour profiles that resemble traditional beverages and can be used to achieve fermentation with higher attenuation. This offers greater fermentation efficiency in, for example, the development of low-calorie beers. Additionally, the ability of diastatic strains of S. cerevisiae to convert non-fermentable oligosaccharides to fermentable sugars enables applications that range from novel beverages using unusual raw materials to more efficient distillation and biofuel production. The negative attributes that are associated with diastatic S. cerevisiae yeasts can be managed through co-inoculation or hybridisation with standard strains.