dg61 wrote:Just chipping in to note that people drinking beer because it has antibiotic properties is a widespread myth; there's not a lot of evidence people actually drank beer to avoid bacteria and as others have said the alcohol content would not sterilize it-you'd have to drink alcohol at poisonous concentrations for that. ... Medieval and other pre-modern people mostly drank alcohol for the same reasons we do today-for the calories in some cases(if one was engaged in hard labor) or simply for the pleasurable mood-altering effects.
All pretty much correct. But understanding of the (relative) safety of fermented beverages, and also pickled foods, goes way back, even among people with no concept of micro-organisms. People also recognized the possibility of spoilage, and in many areas learned ways of decreasing it. This was one of the documented reasons for distillation. Yeasts can get the alcohol content up to around 12%, but there are things that can live at that level. But if you've learned how to distill off the alcohol, you can add it to other things, including batches of wine or beer, and get an even higher alcohol level that won't spoil. Thus, sherry is made by distilling part of the wine and mixing the resulting brandy with the remaining wine, to get around 18% alcohol.
And part of the evidence that this is what was going on is all the historical comments about diluting fermented beverages, often with boiled water or freshly-pressed fruit juices, before drinking. This can be interpreted as evidence that many people weren't trying to get drunk; they'd just learned that the results tasted good and didn't make you sick.
In cold areas, e.g. Scandinavia and Russia, they didn't even have to distill their booze. People have long used freezing to remove part of the water, raising the alcohol percentage in the resulting liquids. This has been especially common with ciders, but has been done with anything that can be left outside overnight to form a layer of ice on top. This works well, but also concentrates the flavor, and the result can be too strong for most people's taste. So they look for safe ways to dilute the results. Such concentrates have also been widely used in cooking. As someone else pointed out, this does typically drive off most of the alcohol, but then it's in the air and everyone is breathing it, especially the cooks.
Some of my acquaintances who brewed beer have commented that it's no surprise that beer (and the distilled form, whisk(e)y) are among the safest drinkables. They usually comment on how they have to be fanatics about cleanliness, boil the juices thoroughly, keep the containers sealed, etc. If they screw this up, they don't get beer; they get disgusting slop that nobody will drink. It's a lot more difficult than distilling fruit juices, and has historically been done by beer-brewing specialists. The result is that home-brewed wine is usually safe, but not always, while home-brewed beer not done right is simply discarded as undrinkable.
OTOH, I grew up in the Seattle area, which like most of the US west coast is a natural wine-producing area. Lots of people there get some very good (if highly carbonated) cider by buying gallon jugs of fresh apple juice (without preservatives), and putting them in a closet for a week or two. You can drink it at any time, of course, but people wait until it fizzes well when you loosen the lid. I never knew anyone who got sick from it. Then I moved "out east", and when I tried it, I just got disgusting slop that I wasn't about to drink. So now I have to buy cider, and most of it's too sweet.