Coffee Water in 2026: The Old Rules Are Dead💧 — Transcript

Full transcript

1. 0:00So, today is actually the World Water
2. 0:03Day and that means that we need to talk
3. 0:05about coffee water, which is, of course,
4. 0:08one of my favorite subjects and not
5. 0:10because I love chemistry, but because
6. 0:11it's so important to get right if you
7. 0:13want the tastiest brew. So, for years
8. 0:16the coffee world told you two things
9. 0:18about water, hit 150 TDS and keep your
10. 0:22general hardness double in relation to
11. 0:24your carbonate hardness. Specialty
12. 0:27coffee treated these like laws. Barista
13. 0:29training,
14. 0:30YouTube videos, forum posts, all built
15. 0:33around these numbers and they're
16. 0:35basically both wrong. Not slightly off,
17. 0:37but completely at odds with how the best
18. 0:40baristas in the world think about water.
19. 0:42I know that's a bold claim, so in this
20. 0:45video I will show you the evidence and
21. 0:47give you a clearer understanding
22. 0:50of how you can achieve the perfect water
23. 0:53for coffee without going back to your
24. 0:56old chemistry books from high school.
25. 0:58So, let's get into it. For quite a long
26. 1:00time, water pretty unexplored by the
27. 1:03coffee community, but then around 15
28. 1:05years ago more information started to
29. 1:07appear with the Specialty Coffee
30. 1:09Association's water handbook. Then
31. 1:12around 10 years ago, the book Water for
32. 1:14Coffee was released. And while these
33. 1:17books were released from a kind of noble
34. 1:19idea of sharing more advanced knowledge,
35. 1:22some of the theories that were presented
36. 1:25became kind of monolithic in the world
37. 1:27of coffee. Almost everything that has
38. 1:30been written, said, and done in the
39. 1:32space has been reacting to these two
40. 1:35books. So, when I ask you to disregard
41. 1:37all these old dogmas, it's not because I
42. 1:39want to be controversial just for the
43. 1:41sake of it. It is actually to help you
44. 1:43make better coffee that is more in line
45. 1:46with how top baristas and the top brands
46. 1:49in the industry think about water for
47. 1:51coffee currently. So, let's just look at
48. 1:54a few theories that were super dominant
49. 1:565 to 10 years ago that I think you
50. 1:59should be careful with now. So, the
51. 2:01first theory is that you must have a
52. 2:03general hardness that is exactly double
53. 2:06the carbonate hardness. For example,
54. 2:08that could be a general hardness that is
55. 2:1080 ppm and a carbonate hardness that is
56. 2:1340 ppm. So, that would be a 2:1 ratio,
57. 2:17but that is just not something that's
58. 2:19being followed at the highest level
59. 2:21anymore. And to prove that, you can just
60. 2:23take a look at the World Brewers Cup
61. 2:25finals in 2025. None of the nine
62. 2:28finalists followed that dogma and
63. 2:31actually 44 out of 50 competitors used a
64. 2:34brand called Apex Lab, this one here.
65. 2:37And if you measure the carbonate
66. 2:39hardness of Apex Lab water, which I have
67. 2:42done, I know a little bit geeky, but
68. 2:44then you can see that it's just a very,
69. 2:46very low level. There's also another
70. 2:49brand named Aquacode, which is also
71. 2:51quite popular and used among some
72. 2:53competitors. And this brand is actually
73. 2:55even more extreme because their mineral
74. 2:57concentrate doesn't contain any
75. 2:59carbonate hardness at all. But one thing
76. 3:01I always wondered about is
77. 3:04the alkalinity in Aquacode. Uh-huh. My
78. 3:06my suspicion has always been that it's
79. 3:08close to zero. Yeah. Can you confirm
80. 3:10that the KH is zero of Aquacode? Yes, uh
81. 3:14according to our research team. Yeah.
82. 3:16And they say we are 100% natural and we
83. 3:20don't have KH
84. 3:21uh compound in Aquacode.
85. 3:24Now, what about the idea that the ideal
86. 3:26TDS is 150 like the SCA recommended for
87. 3:30a long time? Again, this is also
88. 3:32something that one shouldn't really
89. 3:33follow as a strict rule. I became quite
90. 3:36skeptical about it already 10 years ago
91. 3:38when I read a blog post from the Coffee
92. 3:40Collector from Denmark where they
93. 3:42recommend a TDS of only 30 ppm. And at
94. 3:46first I couldn't get it to fit with what
95. 3:48the SCA was saying, but as I
96. 3:50experimented more and more, I just
97. 3:52realized that generally I also preferred
98. 3:55the softer water. However, there were
99. 3:58also times when the soft water was a
100. 4:00little bit too acidic and then I
101. 4:02realized that actually there is rarely a
102. 4:04value that is perfect for all coffees.
103. 4:07It also depends on how the coffee is
104. 4:09roasted, what tastes the best.
105. 4:11So, strict ideas about numbers, don't
106. 4:14let them dictate your coffee water. And
107. 4:16by the way, at the 2025 Brewers Cup
108. 4:20final in Jakarta, which I referred to
109. 4:22just before, the winner, George Peng,
110. 4:25used a water that had only 40 ppm TDS.
111. 4:28Now, what about the humble TDS meter,
112. 4:31this one here? Well, around 10 years
113. 4:33ago, the TDS meter also started to
114. 4:36become vilified as something that was
115. 4:38completely useless for coffee water. And
116. 4:40it's true that TDS on its own doesn't
117. 4:43tell you
118. 4:44that much. It's a little bit like
119. 4:45looking at a body weight using a
120. 4:48bathroom scale when you're trying to
121. 4:50assess someone's health. So, body weight
122. 4:53tells you the total mass, but not how
123. 4:55much is fat or muscle. And it also
124. 4:58doesn't tell you if the person being
125. 4:59measured is a marathon runner or an
126. 5:03Olympic sprinter. But that doesn't mean
127. 5:05that the bathroom scale is useless. It
128. 5:07can still be helpful if you have some
129. 5:09data about the person in question. For
130. 5:11example, let's say it's a professional
131. 5:12sprinter who's 6 ft tall. Well, then I
132. 5:15would expect a certain kind of weight
133. 5:17that would be very different from the
134. 5:18marathon runner. And it's a little bit
135. 5:20the same with the TDS meter. If you do
136. 5:23know something about the water that
137. 5:25you're measuring with this one here,
138. 5:26then it can be really useful. For
139. 5:28example, let's say you have a very soft
140. 5:30water, this one here, and you have a
141. 5:33very hard water,
142. 5:34this one here. Now, if you want to mix
143. 5:36them, a TDS meter is actually a really
144. 5:39useful way to go about it, just to get
145. 5:41into the right ballpark. So, using a TDS
146. 5:44meter for practical things like that is
147. 5:46actually really useful and helpful and I
148. 5:49still use a TDS meter almost on a daily
149. 5:51basis. And even if you don't know what's
150. 5:54exactly in that harder water, you can
151. 5:56still experiment and scale it up and
152. 5:58down a little bit like turning a knob.
153. 6:00So, you can be fairly sure that you'll
154. 6:03get more general hardness and more
155. 6:04carbonate hardness by increasing the
156. 6:06proportion of the harder water,
157. 6:09especially if it's a natural water. So,
158. 6:11in natural waters, general hardness and
159. 6:14carbonate hardness usually follow each
160. 6:16other quite closely as a pair. It's only
161. 6:18when people start to play around with
162. 6:20different mineral concentrates like
163. 6:22these ones here that you'll see this
164. 6:24pair being broken up. So, my suggestion
165. 6:27is this, find a very soft bottled water,
166. 6:31maybe something with 10 to 30 TDS, brew
167. 6:33with it, then slowly mix in a little bit
168. 6:36more of a harder water and see what that
169. 6:38does to your coffee. And throughout this
170. 6:41process, a TDS meter is really helpful.
171. 6:44So, the next step is about the pre-made
172. 6:46mineral mixes and this has become a bit
173. 6:48of a trend in coffee water. And there
174. 6:51are good and bad sides to this, but if
175. 6:54you start experimenting heavily with
176. 6:55these before you really understand what
177. 6:57tasty natural water can be like, then
178. 7:00you'll probably just waste a lot of
179. 7:01money and not get that great tasting
180. 7:03coffee any faster. So, if we take a
181. 7:06brand like Third Wave water for example,
182. 7:08I think there are good things to say
183. 7:10about this brand, but the way they have
184. 7:12formulated the water profile is to hit
185. 7:15150 TDS because the old recommendation
186. 7:18from the SCA was that that's what you
187. 7:21need to hit. But what we understand now
188. 7:23is that this is not a magic number. It's
189. 7:25more just an arbitrary number and for
190. 7:28that reason, many people actually prefer
191. 7:31Third Wave water at half strength or
192. 7:33even 1/3 of that 150 TDS strength. So,
193. 7:37instead of thinking of minerals in a
194. 7:40strictly scientific way, a more healthy
195. 7:43approach is just to treat them like a
196. 7:45spice mix. You add a little bit and it
197. 7:47might give you a tasty result. And it's
198. 7:51a little bit the same because nobody
199. 7:52follows a cooking recipe that says add
200. 7:55exactly 4.37
201. 7:58g of cumin. Instead, you taste, then you
202. 8:01adjust, and then you find what works
203. 8:04with this dish that you're making. And
204. 8:06water is exactly the same. Soft water is
205. 8:09your kind of like blank canvas. It lets
206. 8:12coffee's natural character come through,
207. 8:15but a little bit of calcium can enhance
208. 8:17the body, some bicarbonate can reduce
209. 8:20the acidity, round off the cup a bit
210. 8:22more, maybe even add a little bit of
211. 8:24sweetness. But I don't think you need a
212. 8:26certain amount of calcium to hit a
213. 8:28specific general hardness. Some coffees
214. 8:31taste better with more magnesium than
215. 8:33calcium and this is a bit of a culinary
216. 8:36choice and not a scientific rule. And of
217. 8:38course, I also go more into all this in
218. 8:41my coffee water course. So, I'll leave a
219. 8:43link to that down below.
220. 8:45The next important thing to keep in mind
221. 8:47is whether you're brewing espresso or
222. 8:49filter coffee because they are two very
223. 8:51different drinks with different goals.
224. 8:53So, with filter coffee, you usually want
225. 8:56more acidity because that's what carries
226. 8:58the fruit flavors and makes the cup
227. 9:00interesting. And for that reason, low
228. 9:02carbonate hardness like in a soft water
229. 9:05is desirable. And that means you have
230. 9:07less bicarbonate in the cup and as a
231. 9:09result, you'll have a more acidic and
232. 9:12fruit forward flavor. So, here it's a
233. 9:14little bit like let's say you're making
234. 9:15something fruity and refreshing in the
235. 9:17kitchen, maybe a lemon meringue pie. So,
236. 9:21often just having a low overall mineral
237. 9:23content, a low total TDS, will also give
238. 9:27you that low carbonate hardness. So, for
239. 9:30filter coffee, try using water that
240. 9:31measures between 30 and 80 on a TDS pen
241. 9:34like this and that will probably be a
242. 9:37pretty good starting point. For
243. 9:38espresso, the goal is almost the
244. 9:40opposite. Think less lemon meringue and
245. 9:43more like a brownie or chocolate mousse.
246. 9:45Here, you often want to tame the
247. 9:47acidity. So, espresso can easily taste
248. 9:50too sour, so you generally want to have
249. 9:52more carbonate hardness and that usually
250. 9:55also means a higher TDS. So, here we
251. 9:57have a slightly different culinary goal.
252. 10:00And as a result, we look to science not
253. 10:02to understand what our goal is, but
254. 10:05instead to get help to support our goal.
255. 10:07So, it shouldn't be the other way
256. 10:09around. However, when it comes to
257. 10:11espresso, you have to be careful,
258. 10:13especially if you're using mineral
259. 10:14concentrates, because many of them are
260. 10:17very high in chlorides, and chlorides
261. 10:19can be really corrosive to your espresso
262. 10:21boiler over time. That's it for today. I
263. 10:23will probably see you in another coffee
264. 10:25video very soon.