# 🍺 NOTES - BEER
## Remember
* Avoid buying IPA older than three months, and pick beer in a beer fridge over beer on a shelf
Beer is made with four major things: water, malt (usually barley), hops, and yeast
* **Water**: The primary component of any beer, water quality and mineral content significantly influence flavor
* **Malt**: This gives beer its sweetness and body, acting as a counterbalance to the bitterness from hops
* **Hops**: They are responsible for the intense aroma and bitterness, and their volatile oils are sensitive to temperature
* **Yeast**: While yeast plays a crucial role in fermentation, diminishes after the fermentation process is complete
## Bacteria
lactobacillus bacteria (lovingly referred to as “lacto” in the beer world) creates lactic acid, which results in the relatively clean lemony-tart puckering sour you recognize in beers;
pediococcus bacteria (which also gets a cute nickname: pedio), which also creates tart lactic acid but also brings funkier side notes; acetobacter (which *DOESN’T* get a cutesy nickname, which sucks!), the same bacteria that turns wine into vinegar and creates acetic acid, giving (surprise!) sour vinegar flavors; and
brettanomyces, a wild yeast (woo, outlier!) known as “brett” for short that creates a drier, funkier set of flavors.
## Chilled beer - why IPAs
chilled beer is better to buy than room temperature … but only by a small margin
all canned and bottled beverages sold in the United States go through a pasteurization process
pastuerization stablizes flavors
but...chemical reactions slowly alter flavor in food...this happens far slower at cooler temperatures, which is why we store some products in the fridge and freezer
once a beer declines in flavor or aroma, there's really no reversing the effect
unopened beer has a months-long shelf life
hops tend to lose their more delicate flavors when stored at warmer temperatures (anything above 40 degrees Fahrenheit), becoming more and more bitter the longer they sit outside of a cool environment. Conversely, when stored at colder temperatures, the hops' flavors and complex aromas can be better preserved
Temperature plays a critical role in the longevity and flavor profile of IPA. Hops are particularly susceptible, as their aromatic oils can degrade over time when exposed to heat (oxidation) or light (lightstruck/skunking)
Alcohol content over 7% are less influenced by temperature changes because higher alcohol acts as a preservative