1. The third most popular drink overall, after water and tea.
What is Beer?
The third most popular drink overall, after water and tea.
More than 133 billion liters (3.5×1010 U.S. gallons; 2.9×1010 imperial gallons) are sold per year—producing total global revenues of $ billion
Beer is one of the oldest beverages humans have produced, dating back to at least the fifth millennium BC and recorded in the written history of ancient Egypt and Mesopotamia and was spread throughout world.
Alulu beer receipt – This records a purchase of "best" beer from a brewer, c BC from the Sumerian city of Umma.
The Sumerian IRS expected proofs-of-purchase to be set in stone…

2. A funerary model of a bakery and brewery, from the Eleventh dynasty of Egypt, circa 2009–1998 BC
Beer was part of the daily diet of Egyptian pharaohs over 5,000 years ago. Then, it was made from baked barley bread, and was also used in religious practices.[31] During the building of the Great Pyramids in Giza, Egypt, each worker got a daily ration of four to five liters of beer, which served as both nutrition and refreshment that was crucial to the pyramids' construction.
Who made beer? Alewives! Beginning in the 18th century, women were increasingly barred from the business of brewing, except as barmaids or "publicans", licensees running pubs

3. The grains are usually malted, exposed to water and left to germinate (sprouting). This helps releasing the starches in the seeds and turn them into sugar by the action of amylase. Then, the grains are kilned and milled.
The grains and water are mixed into a mash. Enzymes in the grains break down the starches into sugars, such as maltose.
Lautering: the mash is separated into a sugary wort fluid and the residual grain. Hops are added and boiling follows  hops flavoring is released, the wort is sterilized from unwanted bacteria and other microcritters. Why are the hops added prior to boiling?
The wort is cooled, yeast is added:
Sugar  alcohol + carbon dioxide (bubbles)
Filter, condition, bottle or keg. Bottling requires pasteurizing, not good for taste. Kegged beer tastes better, but has a limited lifespan.

4. Hops are the flowers of the hop plant Humulus lupulus
Hops are the flowers of the hop plant Humulus lupulus. They are used primarily as a flavoring and stability agent in beer, to which they impart bitter, zesty, or citric flavors.
Gruit is an old-fashioned herb mixture used for bittering and flavoring beer, popular before the extensive use of hops. Gruit or grut ale may also refer to the beverage produced using gruit.
Gruit was a combination of herbs, commonly including sweet gale (Myrica gale), mugwort (Artemisia vulgaris), yarrow (Achillea millefolium), ground ivy (Glechoma hederacea), horehound (Marrubium vulgare), and heather (Calluna vulgaris).
Hops tended to better a better preservative. However, brewers tended to use whichever was not taxed by the authorities…
Purity Law: the only ingredients used for the brewing of beer must be Barley, Hops, and Yeast.
In reality, it made for easier enforcement of levies charged on beer ingredients. The Puritan also prohibited gruit because of its “aphrodisiac and stimulating effects” by imposing “sedating” hops instead.
In March 1987, in a case brought by a French brewer, the European Court of Justice found that the Purity Law was protectionist, and therefore in violation of Article 30 of the Treaty of Rome.
However, the law had already had a long negative effect on creativity and variety.

5. Hop cones contain different oils, such as lupulin, a yellowish, waxy substance, an oleoresin, that imparts flavor and aroma to beer. Lupulin contains lupulone and humulone, which possess antibiotic properties, suppressing bacterial growth favoring brewer's yeast to grow.
Many plants secrete bitter, bacteriostatic secondary metabolites: nicotine, morphine, cocaine, colchicine, strychnine, quinine help warding off herbivores with their bitter taste and suppress bacteria, viruses, and parasites.

6. Alpha-acids. Unboiled hops are only mildly bitter
Alpha-acids. Unboiled hops are only mildly bitter. During the boiling, humulone isomerizes to cis- and trans-isohumulone. These “alpha acids” survive the boiling process, although numerous oxidized derivatives are produced. The iso-alpha acids are significantly more soluble than humulone at the pH levels typically present in the brewing process. On the other hand, the non-bitter flavor and aroma of hops come from the essential oils, which tend to evaporate during the boil.
Essential oils: The more volatile components. The concentration of humulene varies among different varieties of the plant but can be up to 40% of the essential oil. It was found that the hydrolysis products of humulene epoxide II specifically produces a “hoppy” aroma in beer.
Aroma hops are typically added to the wort later to prevent the evaporation of the essential oils, to impart "hop taste" (if during the final 30 minutes of boil) or "hop aroma" (if during the final 10 minutes, or less, of boil). Aroma hops are often added after the wort has cooled and while the beer ferments, a technique known as "dry hopping", which contributes to the hop aroma.

7. The 1990s microbrewery movement in the U. S
The 1990s microbrewery movement in the U.S. and Europe saw a renewed interest in unhopped beers and several have tried their hand at reviving ales brewed with gruits, or plants that once were used in it. Commercial examples include:

8. The process is anaerobic
The process is anaerobic. Atmospheric oxygen would oxidise the ethanol to carbon dioxide.
First to appear: Top cropping is a method of harvesting yeast from beer that is in the 2nd or 3rd day of active fermentation.  Ale yeast are also known as top-fermenting yeast.  During fermentation the unique shape of the ale yeast's surface allows it to attach to rising CO2 and travel to the beer's surface.  Top cropping was the norm years ago.  It is how breweries managed to reuse yeast for hundreds of years. Ale yeast likes warmer temperatures.
There are literally hundreds of varieties and strains of yeast.
Saccharomyces cerevisiae

9. Lagers are relatively new to the brewing scene
Lagers are relatively new to the brewing scene. They first arose in Bavarian breweries in the late 15th or early 16th century, then eventually spread to the rest of Europe (most famously to Plzeň, the birthplace of pilsner) and eventually to the rest of the world. All of
those beers you think of as "national" brands -- Heineken, Tsing Tao, Sapporo, Kingfisher, Budweiser to name just a few -- those are all
lagers.
Lager yeast, Saccharomyces pastorianus, possesses many similarities to that of ale yeast, Saccharomyces cerevisiae -- it in fact has whole stretches that are identical to S. cerevisiae. But lager yeast works best in cold temperatures -- temperatures that would make an ale yeast go dormant. Further, unlike ale yeast, no "wild-type" lager yeast has ever been found in
Europe and lager yeast need humans to continue its propagation. Finally, ale yeast usually spends its life as a diploid organism. Lager yeast is what biologists call "allotetraploid": it has four copies of its genome, which is made up of genomes from two different species.
Credit: Popular Mechanics

10. So, where did lager yeast S. pastorianus come from
So, where did lager yeast S. pastorianus come from? And why did it only show up in the 1500s, thousands of years after
humans figured out how to brew with S. cerevisiae?
The scientists knew through prior research that Saccharomyces species thrive on oak trees in Europe. After collecting samples from forests all over the world, they isolated two cold-tolerant yeast strains from the forests of Patagonia in Argentina: S. eubayanus.
Many distinct strains of S. eubayanus exist in South
America, which strengthens the argument that the strain is indigenous to the area.
S. pastorianus -- lager yeast -- is a hybrid of S. cerevisiae and S. eubayanus.
Two sets of lager yeast chromosomes are from ale yeast, and two are from this wild Patagonian species.
The Patagonian species is what gives lager yeast its interesting cold-tolerant and sulfite-metabolizing characteristics--
characteristics that manifest in the distinctive flavor and character of lager beer.

11. Lager beer is fermented and then "lagered" (stored) in caves for a period of weeks or months at temperatures hovering in the 40s Fahrenheit. This low-and-slow fermentation means that lagers taste "clean" and lack the fruity esters characteristic of ales. Further, because of the sulfite metabolism, lager beers usually smell a lot like rotten eggs during fermentation (this is normal), and a very slight bit of dimethylsulfide (DMS) character in the end
beer is considered proper for the style.
The researchers speculate that hitch a ride
it did during the early years of trans-Atlantic trade, then eventually ended up in the cold-fermenting vats of Bavarian beers. There, S.
eubayanus fused with S. cerevisiae to form a hybrid strain, which then evolved in the brewing environment by dropping some genes here and there -- the cold and high-alcohol environment of a brewing vat made sure to kill off any unfit mutants -- to the new brewing strain S. pastorianus: the modern lager yeast.
Credit: Popular Mechanics

12. And now for the fun part!
PatentBase search on “beer”, : 9217 hits!
Let’s filter out less relevant technologies…
Beer bottle: 1031
Product design: 937
Beer barrel: 163
Beer dispenser: 122
Beer keg: 71
…and focus on beer-making and such.