today we're uncovering the most common crimes against coffee some are subtle some are surprising
most are unintentional but they're happening every day in home kitchens around the world the
first step is admitting we have a problem so let's take a deep breath as i dish out some tough love
hey it's josh from seven miles coffee roasters coming to you from my lounge room thanks to
sydney's current covid lockdown and speaking of being stuck at home it's high time we shine a
light on some bad coffee habits we'll start with a problem that's so widespread it's basically
expected people often ask how long does coffee last they take a look at the best before date on
the bag which on many coffees might say six months or 12 months from when it was packed
while it's true that coffee is safe to drink at this point you're really not going to get any
great results with a coffee that's a year old with old coffee typically you'll find that you get very
little crema and you'll quite often get a very flat bland tasting espresso in tests by our coffee
science and education center we found that most coffees hit their peak flavor at around 14 days
after they're roasted yep two weeks that's not to say that coffee cannot be tasty after this point
but within a few weeks after the coffee has roasted coffee starts to steady decline into
blah we found that the ideal range for coffee varies with the exact packaging method and roast
but for most coffees we got a good result in a range from two weeks up to a maximum of eight
weeks after the roast date assuming the coffee was packed oxygen free and kept in its original
packaging unfortunately old coffee isn't the only cause of stale coffee the second freshness
killer is once the coffee is exposed to oxygen you know like once you've opened the bag you
can minimize the effects of oxygen by using an airtight container but ultimately unless
you're using the whole bag within a few days we found that your best to store open bags of coffee
in an airtight container in the freezer yes yes i realize some people out there on the internet
say the freezer is its own crime against coffee but the data does suggest otherwise
in our tests open bags of coffee stored in the freezer performed significantly better
in blind taste tests than the same coffee stored in the fridge or at room temperature
the last tip i'll give you about coffee freshest is probably the most important
you really need to get a grinder grinding the coffee speeds up the staling process significantly
so buying a pre-ground means that you're already fighting a losing battle on that freshness scale
the second mistake is ignoring the brew ratio i know that there are some that
would rather just freestyle in the kitchen but if you want consistently tasty results
a little maths can go a long way so brew ratio is simply the ratio of amount of ground coffee to the
amount of liquid espresso this ratio can have a big impact on the flavor espresso you end up with
so it's definitely worth finding a balance that tastes good for the coffee that you're drinking
we usually write this down as a recipe for example for this coffee we recommend using 21 grams of
ground coffee to brew 40 grams of liquid espresso in a time of 26 to 30 seconds if the machine
you're using has larger or smaller baskets you can adjust the weight of the espresso shot at the same
ratio so if you're using 18 grams of ground coffee i'll reduce that liquid espresso to 34 grams
to maintain the same ratio and balance of flavors but now if you're a nerd like me the
easiest way to manage this is to use some digital scales that way you're always spot on target
but if that's too intense for you then you can still control the ratio by using some old school
methods like filling and swiping the portafilter or programming the brew volumes on your machine
the third mistake is using random cup sizes if you drink coffee with milk like say a flat white
a latte or a cappuccino then the amount of milk you add to the espresso will have a big impact on
the taste of the finished product you'll notice that most specialty cafes use smaller cup sizes
than the cups you may have lying around at home these sizes are selected to give you an ideal
balance of espresso and milk when filled to the top the ideal ratio varies a little depending
on how dark the coffee is roasted or how the flavor plays with milk but a good rule of thumb
is that you generally want no more than around 160 to 180ml of milk per shot of espresso so for a
double espresso try to find a cup that's no larger than 300 to 350 mls yes i know you love that jumbo
world's best dad mug you got for father's day but maybe save it for the hot chocolate because we can
never have enough of that mistake number four is ignoring water quality the water you use to brew
your coffee can affect the flavor in two ways the first it can taint the flavor of the coffee
if you're using plain old tap water you'll most likely be getting chlorine and metallic taste
from the pipes in your house a simple carbon filter will generally get rid of most of these
and so it's a real simple way of improving the flavor of your coffee straight out of the gate the
second way that water affects the taste of coffee is a little more technical the chemistry of water
itself affects the balance of flavors that you can extract from the coffee dissolved minerals
like magnesium and calcium as well as the acidity of water all have an effect on the way that the
coffee tastes i won't go into the details now but if you're interested in how this works i'll
link up to a more technical video up here if you want to nerd out in some water for coffee for now
i suggest just starting out with a basic water filter to get rid of those flavor
taints speaking of ingredients that can turn a good coffee bad our next mistake is milk abuse
the most common example is burning the milk if you're making a cappuccino a latte or a flat
white then it's a mistake to heat the milk to the same temperature as the coffee i know i know some
people like that flat white to be piping hot but milk based coffees like these just don't taste
right at high temperatures most milks are at their best when they're heated up to around 65 degrees
celsius to around 70 degrees celsius beyond this point milk will start to taste cooked and that is
less sweet with a little bit more of an eggy aroma the higher temperatures also make it harder to get
silky milk texture which we'll get to in a second getting the right temperature is pretty simple
you can either use our old-fashioned touch temperature method that many baristas use
and develop over their career or you can use a milk thermometer like these stickers that change
color when the milk hits the right temperature the texture of the milk also has an effect on flavor
if you inject too much air into the milk you'll end up with fluffy peaks of milk foam that quickly
separate out into layers that float around on the top of the cup but these larger bubbles of milk
foam tend to accentuate the bitter notes of the coffee whereas a more silky creamier milk texture
will blend with the espresso and give a bit more of a balanced flavor of course some people prefer
re-enacting the final moments of the titanic on their cappuccino so each to their own i guess
our final mistake is the hidden menace the thing that no one wants to talk about dirty equipment
most of us are pretty good at keeping the outside of our shiny new espresso machine clean
but we do tend to let the team down when it comes to parts we can't see after we make
a few shots of espresso the coffee oils coat the surfaces in the group head the portafilter
and the basket this residue bakes on creating all manner of metallic rancid and generally
unpleasant flavors and aromas i mean just take out that basket and take a sniff
that's what's waiting for your next coffee at the risk of sounding like a late night infomercial
the solution is pretty simple just get some espresso cleaner these cleaners are designed
to remove this coffee residue and a jar of this stuff will last you a really long time
keeping your home coffee equipment free from those dank coffee vibes most manual home espresso
machines come with a blind filter or a cleaning disc that you use to back flush the group head
use this with a small amount of espresso cleaner and flush it back through the group a few times
if it's really nasty you might need to leave it to soak for just a few minutes once that's done
empty out the dirty water and flush it through a few more times with plain water to remove any
of the residue from the espresso cleaner next separate the portafilter and the basket and soak
them in hot water with a scoop of espresso cleaner after five minutes you can give them a quick scrub
a rinse and you're ready to get back to making good coffee that doesn't taste like an ashtray
and with that i wish you the best of brews at home till next time stay exceptionally stoked