Why Does My Coffee Taste Watery/Weak?

December 6, 2018

You put that cup to your lips and take a sip of the good stuff… but the taste is thin and watery, nothing like what you were hoping for? What gives…?

Watery coffee is the worst. For me, drinking my coffee is the highlight of my morning and the supercharged ‘buzz’ I get sets me up for the day, so strength is pretty darn important.

So what makes coffee taste watery?

There are three main mistakes you can make that will result in a coffee that tastes thin and lifeless, they are…

1. Using a weak strength ratio. Essentially, putting too much water or too little coffee in the brew. (Read a bit further to find out what ratios give what levels of strength).

2. The coffee is being underextracted. This one’s a little more technical and requires you to understand how the brewing process works but is a surprisingly common issue for a lot of home brewers.

3. You’re not drinking enough. For many people, watery coffee is associated with the coffee being ‘weak’ and you may simply have to drink more to get that caffeine buzz that comes with strong coffee.

Now if you wanna learn how to brew so you never get hit with a watery coffee again, then scroll a little further and I’ll tell you everything I know.

Reason #1: Brew Strength Ratio Is Wrong

Usually the problem when… you don’t measure how much coffee or water you put in.

When you really start getting into brewing your coffee at home, one of the first things you must do is use a scale to measure your ratios.

Here’s a rough guide to what kind of ratios give what kind of coffee (coffee grounds is first and water is second).

STRONG -> 1:11
MEDIUM -> 1:15
QUITE WEAK -> 1:17
WEAK -> 1:20

(By the way, we like to use grams and milliliters in the coffee world as they’re smaller than ounces and so more appropriate.)

For example, let’s say you use 15g of coffee and 225g of water, that gives you a nice ratio of 1:15 which is somewhere in the middle which is considered ‘Medium’.

Of course, this is all subjective and your viewpoint on what is weak and strong may be different to the general consensus.

I would recommend that you measure your coffee:water ratio and see where it falls on this list.

If it’s ‘WEAK’ or ‘QUITE WEAK’ then look at adjusting your ratio by either adding a little more coffee or reducing the amount of water and see if that satisfies your taste buds.

If your coffee falls in the ‘MEDIUM’ or higher range then the likeliest problem is that your brew process is underextracting the compounds from the coffee beans. In this case, you need to go on to Reason #2.

Reason #2: The Coffee Is Underextracted

Usually the problem when… the taste of the coffee is a little grassy or acidic.

The extraction of your coffee is what’s going on when you brew and is an incredibly important part of the brewing process.

Coffee is not like tea. You cannot let it sit for a few minutes and be safe in the knowledge that a minute or two extra or less is not going to make any difference.

Coffee is a finicky substance that can go wrong very, very easily.

If you extract too little, perhaps because you don’t brew for long enough or your grind is too coarse, your coffee becomes dominated by much of the earlier extracting acidic compounds and can taste thin and watery because not enough of the compounds and oils and everything in the coffee beans have been absorbed into your drink.

As an aside, this is why an overly acidic taste is an obvious marker for the reason your coffee taste watery being due to an underextraction.

The good news is the solution to this is simple, the bad news is that the solution is not easy. To extract more, you just need to increase the brew time, the water temperature or make the grind of your coffee finer.

Which one you select depends on your brew.

For a French Press, it’s easy enough to brew it for an extra minute. For a Pour Over you can’t change the brew time so making your grind finer is probably the way to go.

The tricky part comes by getting the variables just right. So let’s say you brew that French Press for one minute longer. It might taste a lot nicer, with minimal acrid tastes. In this case, great!

But what about if you brewed for just 30 seconds longer, that might be the sweet spot that turns your coffee from ‘great’ to ‘amazing’.

Likewise, you might overdo it and cause an overextraction, the calling card of which is noticeable bitter flavors in your coffee. In which case you need to dial the brew time back a bit, but by how much?

In this way, coffee is very much a refining process. If you’re really interested in making awesome coffee then you will need to play around with the variables until you get something that is really fantastic.

And when you do, all that refining and adjusting is totally worth the wait.

Reason #3: You Aren’t Using Enough Coffee

Usually the problem when.. the coffee tastes fine but you don’t get enough of a buzz.

The last problem, and the least likely, is that you are not drinking enough coffee.

If the coffee is tasting good and tasting strong then you know that your strength ratio is acceptable and you must be extracting enough. The next thing to look at is the amount of coffee you’re using in a cup.

A typical range for ground coffee is 12-30g for a drink. The average caffeine content for a gram of coffee is 13.5mg, so take a look at this table to see how much caffeine you get in a drink.

12g coffee – 162mg caffeine
17g coffee – 230mg caffeine
20g coffee – 270mg caffeine
25g coffee – 338mg caffeine
30g coffee – 405mg caffeine

To put this into context, a typical decent sized coffee is considered to be about 150-200mg with larger coffees going above that. The RDA states that up to 400mg per day seems to be healthy in adults.

Personally, in my experience with people who really love their coffee, these numbers are a little on the low side.

Also, note that the amount of coffee that used to give you an awesome buzz can become more ‘weak’ over time.

It’s a sad fact that we build up our tolerance to the caffeine in coffee over the years and you may need to increase the amount you are drinking to still feel the same ‘rush’.

What Other Flavors Tell You About The Brew

Bitter – If your coffee is tasting bitter it’s highly unlikely it will also taste watery. Bitterness is caused by an overextraction, when you brew for too long the later-extracting bitter compounds come to dominate the brew.

This causes very unpleasant tastes and can ruin your brew. It’s often a danger among people who are trying to aim for a ‘strong’ coffee and just end up with a coffee that tastes bad.

Sour – If your coffee tastes sour or acidic then this is a clear sign of an underextraction, where you brew for too short an amount of time which causes the earlier extracting acidic compounds to dominate the brew.

Considered the opposite of bitterness, balancing these two flavors is a delicate exercise that once mastered, puts you into the top 5% of home coffee brewers.

How To Eliminate Negative Flavors In Your Coffee For Good

If you’d like to go even further down the rabbit hole and explore more nuanced tastes like ‘vegetal’, ‘beefy’, ‘overwhelming’ and a whole bunch more, let me introduce you to the Coffee Compass.

This was designed by the guys over at Barista Hustle and provides you with a framework for achieving the perfect balance of strength and extraction by way of a diagram using a compass.

It supports much of what I’ve written about in this article and takes it one step further with a handy little ‘how to’ guide. Check it out!

You Might Also Like

No Comments

Leave a Reply