Learning how to brew your own beer at home can …
Hops do not add alcohol content to beer as they are simply used during the brewing process to add flavor and aroma to the finished beer. Hops used in brewing are the flowers, or cones, of the Humulus Lupulus plant and contain no fermentable sugars which could be converted into alcohol during the fermentation process.
Hops add an insignificant number of calories to beer through the extraction of hop oils during the brewing process where they are boiled or steeped in the beer to add flavor and aroma to the finished beer. Hop-heavy beer styles such as IPAs typically include more calories because they often have higher alcohol content and unfermentable sugars.
Homebrew beer can come out of airlocks during active fermentation because the explosive growth of yeast and excess carbon dioxide inside the wort can quickly expand to overfill the available headspace inside the fermenter. Using a blow-off tube will allow foam, beer, and yeast to exit the fermenter safely and avoid clogging an airlock.
Any S-shaped airlock or 3-piece airlock works well for fermenting homebrew as long as it is properly sanitized, creates a tight seal with the fermenting vessel, and stays filled with sanitizing solution. Blow-off tubes can be utilized during active fermentation to avoid blowouts and then switched to either an S-shaped or 3-piece airlock later.