Beer is one of the oldest cultural achievements of mankind and one of the most popular beverages all over the world. From the technological point of view, beer has four main properties based on its contents and manufacturing processes. It is (i) pure, (ii) wholesome, (iii) valuable, and (iv) it displays a variety of styles and genres:
(a) The purity is guaranteed by the natural ingredients: hops, malt, yeast, and water. No pathogenic germs are found in beer because of the pH-value, presence of hop substances, the anaerobic environment, the alcohol content and also the fact that yeast metabolizes nearly all fermentable sugars. Therefore, other micro-organisms experience a food shortage. Additionally, the manufacturing process is a clarifying process. Mashing, lautering, boiling, fermentation, and filtration separate harmful or exogenous substances.
[...] Yeast The following are the main criteria for a good brewing yeast: fermentation behavior (bottom or top fermentation), flocculation (powdery or flocculent yeast), fermentation performance (fermentation rate, degree of fermentation), production, and degradation of side products (aroma development, diacetyl removal), as well as intensity of propagation. Generally, yeasts are Saccharomyces yeasts and many breweries have their own yeast strains. In speciality beers different yeasts like Brettanomyces yeasts may also be used. In the brewery, bottom fermenting yeast mostly is cultivated at Pilsener or lager is general representatives of this genre. [...]
[...] The quality of milling has an impact on mashing and lautering and thus on quality of the resulting beer. For example, undissolved malt should be milled finer than well-dissolved malt because physical and enzymatic degradation processes are eased then. Mashing- Grist is mixed with water during mashing. Enzymes dissolute malt substances. Processes are regulated by temperature and its residence time (rest), pH-value, and water grist ratio (affusion). Generally, the same enzymatic processes take place as during malting; amylolysis, proteolysis, and cytolysis. [...]
[...] Quality Criteria of Beer Flavor stability The taste and aroma of beer are not stable. An aged impression arises from the loss of positive flavoring substances and development of an aged flavor. The main reason is contamination with oxygen, which is unavoidable in spite of the latest filling systems. International brewers may add sulfites or ascorbic acid to reduce oxygen impact besides oxygen-poor operation. Beer flavor changes within few days after filling and lasts for several years. Aging starts with a “ribes flavor” that turns into a “cardboard flavor”. [...]
[...] Hemicelluloses and gums are polysaccharides and consist of glucose, hexurone acids and pentosans. β- Glucan is the most important factor in barley that influences the viscosity of wort and beer. Protein content in barley ranges between and One-third may end up in the final beer. Protein is found in the embryo and mostly in the endosperm. It is divided into four fractions: albumins, soluble in distilled water; globulins, soluble in weak hydrochloric acid; prolamins, soluble in alcoholic solutions; and gutelins, soluble in weak bases. [...]
[...] Quality and suitability of these ingredients is absolutely vital for a tasty and beneficial product, as they are for cooking. Purchasing of raw materials for the brewery needs to strictly observe predefined quality criteria. These criteria are as variable as the different types of beer on the market. Water Water is the main component of beer and so breweries often stress the purity and originality of their brewing liquor. Water quality for brewing beer is often determined by legislation. It has to be potable, pure, and free of pathogens, as measured by chemical and microbial analyses. [...]
APA Style reference
For your bibliographyOnline reading
with our online readerContent validated
by our reading committee
