Comparison of the hydrocolloids application efficiency for stabilizing the foam of beer

Subject of research: technology of high gravity brewing, developed to improve production efficiency and reduce energy consumption. This technology has a wide range of benefits, from improving process economics to reducing environmental impact. Investigated problem: despite the presence of significant advantages, there are a number of problems in the technology of high gravity brewing that need to be solved. The main problem is to reduce the foam stability of the resulting beer, which, together with the appearance, aroma and taste, is the most important attributes of the quality of the beverage for the consumer. The stability and texture of the foam depend, among other things, on the quality of grain and hop raw materials, and the course of technological processes. Elevated levels of key malt proteins (LTP1, Z4 and Z7) and hop α-acids have a positive effect on foam quality. Yeast protease A has a negative effect. Yeast secretes this enzyme to a greater extent during fermentation of high gravity wort, which may be one of the reasons for the decrease in foam stability in high gravity brewing. High molecular weight a- and b-glucans with hydrophilic properties can play an important role in foam stabilization. They increase the viscosity of the liquid, slow down its drainage from the foam segments and thereby increase the foam retention. Main scientific results: the effect of hydrocolloids (highly methoxylated pectin, carboxymethyl cellulose, xanthan gum, guar gum, a mixture of xanthan and guar gum) on foam performance and beer filtration rate was investigated. The advantages of pectin as an additive allowing to stabilize beer foam, in particular, in high gravity - brewing, have been established. The recommended dosage of the additive is 0.4-1 g/hl. Highly methoxylated pectin is a good alternative to the currently widespread use of propylene glycol alginate. The area of practical implementation of the research results: brewing companies. Innovative technological product: highly methoxylated pectin as a stabilizing additive for beer foam. Scope of application of the innovative technological product: the use of highly methoxylated pectin as additives that stabilize beer foam, in particular in high gravity brewing.

Comparing the efficiency of applying yeast of different generations in high gravity brewing

When fermenting beer, in addition to the formation of basic, secondary, and by-products, which largely determine the taste and aroma of the beverage, yeast is accumulated. Such yeasts can be reused in subsequent serial repitching, which allows cost savings compared to yeast cultivated for each fermentation. This paper investigates the influence of yeast generation on the progress of the wort fermentation process and the quality of beer obtained, specifically in high gravity brewing. It was established that the increase in the number of yeast generation in the range from the first to the fourth generation causes a slight acceleration of the fermentation process of high-gravity wort, while at higher values of the fermentation generation number it slows down. Yeasts secreted after six or four serial wort fermentations with a gravity of 15 °P/18 °P, respectively, have a good physiological state and can be reused. The yeast generation number does not significantly affect ethanol content and sensory beer quality indicators. However, the use of yeast of the seventh and eighth generation causes a slight increase in the pH and color of high gravity beer, the appearance in the aroma of noticeable extraneous shades ‒ yeast tone, tone of young beer. As wort gravity increases, the number of yeast re-use cycles decreases, which is a consequence of the influence of various stress factors, specifically high osmotic pressure, and increased ethanol levels. Therefore, for the fermentation of wort with a gravity of 15 °P, it is recommended to use yeast up to five generations, for 18 °P wort ‒ to four generations. To obtain beer with appropriate physicochemical parameters and high sensory evaluation in high gravity brewing technology, it is advisable to ferment wort with a gravity of 15 °P with yeast for up to five generations.

Genome Sequence of the Lager-Brewing Yeast Saccharomyces sp. Strain M14, Used in the High-Gravity Brewing Industry in China

ABSTRACT Lager-brewing yeasts are mainly used for the production of lager beers. Illumina and PacBio-based sequence analyses revealed an approximate genome size of 22.8 Mb, with a GC content of 38.98%, for the Chinese lager-brewing yeast Saccharomyces sp. strain M14. Based on ab initio prediction, 9,970 coding genes were annotated.

Optimization of Main Fermentation of High-Gravity Wort

The mathematical model has been developed to calculate the content of higher alcohols and esters depending on wort initial concentration and fermentation temperature. The process was optimized in accordance with the developed model. To obtain high-quality beer via high-gravity brewing technology the wort concentration was found to be 14-15 % relative to dry matter and main fermentation temperature of 284–285 K.

Research Regarding High Gravity Brewing in the Pilot Station USAMV Cluj-Napoca

This paper aims to present preliminary research results obtained while developing and implementing a high gravity beer fermentation process. Production trials were performed in brewery pilot plant from University of Agricultural Sciences and Veterinary Medicine, Faculty of Food Science and Technology. The tehnological parameters were adapted and monitored during the making.