GuinnessGuinness (prononcé ) est une marque de bière ainsi qu'une brasserie irlandaise. Fondée en 1759, celle-ci est devenue une entreprise de taille mondiale avec l'acquisition en 1986 de Distillers Company, un groupe écossais possédant notamment les marques de whiskies Johnnie Walker, Ballantine's ou Chivas Regal. Guinness PLC a disparu en 1997, date de la création de l'entreprise Diageo PLC par fusion-acquisition avec Grand Metropolitan. La Guinness est une stout, une bière noire coiffée d'une mousse blanche, connue mondialement pour sa saveur et son aspect si particuliers.
Yeast flocculationYeast flocculation typically refers to the clumping together (flocculation) of brewing yeast once the sugar in a wort has been fermented into beer. In the case of "top-fermenting" ale yeast (Saccharomyces cerevisiae), the yeast creates a krausen, or barm on the top of the liquid, unlike "bottom-fermenting" lager yeast (Saccharomyces pastorianus) where the yeast falls to the bottom of the brewing vessel. Cell aggregation occurs throughout microbiology, in bacteria, filamentous algae, fungi and yeast.
Mash ingredientsMash ingredients, mash bill, mashbill, or grain bill are the materials that brewers use to produce the wort that they then ferment into alcohol. Mashing is the act of creating and extracting fermentable and non-fermentable sugars and flavor components from grain by steeping it in hot water, and then letting it rest at specific temperature ranges to activate naturally occurring enzymes in the grain that convert starches to sugars. The sugars separate from the mash ingredients, and then yeast in the brewing process converts them to alcohol and other fermentation products.
Beer in EnglandBeer has been brewed in England for thousands of years. As a beer brewing country, it is known for top fermented cask beer (also called real ale) which finishes maturing in the cellar of the pub rather than at the brewery and is served with only natural carbonation. English beer styles include bitter, mild, brown ale and old ale. Stout, porter and India pale ale were also originally brewed in London. Lager-style beer has increased considerably in popularity since the mid-20th century.