FINAL TOUCH 💧

In this blog post ( WATER CHEMISTRY - 3) we mentioned that there is a need to improve existing water resources so that coffee can dissolve well and reach maximum aromas. We emphasized that using tap water directly for brewing coffee would be far from healthy and desired results.

The existing water must be softened to a certain extent. Among the filtering methods used to soften water, reverse osmosis and ion exchange methods have different advantages and disadvantages.

The reverse osmosis method is based on the principle of separating the ions of water by applying pressure through a membrane. This method can reduce the hardness of water because it reduces the ion content of water. However, reverse osmosis can also reduce the mineral content of water because it filters not only ions but also other minerals. Therefore, filtering the minerals that affect the taste of beverages such as coffee can be an undesirable result in some cases.

The ion exchange method, on the other hand, softens water by replacing the calcium and magnesium ions that cause hardness with other ions. In this method, ion exchange resins are used. When these resins are passed through hard water, they retain calcium and magnesium ions and release sodium or hydrogen ions instead. In this way, the ions that cause hardness are removed from the water and the water is softened. The ion exchange method is a more sensitive method and does not affect the taste of the water due to the filtering of minerals.

As can be seen, both methods soften the water, but access to the desired ions is uncontrolled. Although Mg+2 and 1% Ca+2 are continuously given to the water in the reverse osmosis system, the ion feeds required to reveal the coffee aroma will be insufficient. The most important part here is actually the difficulty in accessibility rather than the adequacy of these filtering systems. Since these systems are not economical enough for everyone to use, different solutions need to be found.

Based on this perception, as Meet Lab Coffee, we are happy to introduce our “FINAL TOUCH” product that we produce for professional coffee brewers and will put the finishing touches on your coffee brewing experience. Let’s talk about the purpose and chemistry for which we created our R&D study.

When brewing coffee, we need strong mineral ions that can enter the cellulose walls of the cell for a good extract and combine with coffee components to return to us as flavor. According to SCA and many coffee scientists, Magnesium, Calcium, Sodium and Potassium ions give us this strong mineral structure.

The hardness of water can be increased by adding MgCl2 and CaCl2 salts. This allows the components in the coffee beans to dissolve better. However, excessive use of these salts negatively affects the taste and aroma of the coffee and is undesirable. Therefore, the hardness of the water should be kept at a certain level to achieve optimum solubility of the coffee beans. It should be noted that no matter how much filtering is done in tap water, calcium is found much more than other salts.

Calcium and magnesium salts hydrate with water to form their hydrates. These hydrates dissolve in water as free calcium (Ca²⁺) and magnesium (Mg²⁺) ions. The hydration reactions are as follows:

CaCl₂ + 6H₂O → CaCl₂.6H₂O

MgSO₄ + 7H₂O → MgSO₄.7H₂O

These hydrates are the source of calcium and magnesium ions that cause water hardness. These two salts do not contribute to the softening process of water, but they contribute to the dissolution of compounds contained in coffee. Water that is too hard will have a soap effect and its dissolution tendency will decrease, so the optimum level is very important.

Bicarbonate salts such as NaHCO3 and KHCO3 increase the alkalinity of the water and raise its pH. This is a desirable feature when brewing coffee, as most coffee beans contain acidic compounds. Bicarbonate salts help balance the acidity level when brewing coffee, providing a more satisfying coffee experience. Magnesium (Mg) is usually sourced from MgSO4 or MgCl2 salts. MgSO4 and MgCl2 are both water-soluble salts. However, MgSO4 is more soluble than MgCl2. Therefore, MgSO4 can be seen as a more effective option for reducing the hardness of water, but MgCl2 is much better than MgSO4 in terms of coffee solubility. This is because MgCl2, unlike MgSO4, increases the wettability of water by reducing the surface tension of water molecules. This allows water to flow more easily and can be used as a more effective solvent in the preparation of coffee. In addition, the taste of MgSO4 is more bitter than MgCl2, therefore, in order to prevent undesirable taste changes that may occur as a result of the use of MgSO4, MgCl2 should be preferred, as we use in our FINAL TOUCH product.

So, what kind of water will we use for which coffee region?

Although the answer to this question is relative, it has been observed in several previous scientific studies that the local characteristics of coffee beans can determine the effect of the water used as a solvent.

If we look at the studies in general, it can be said that coffee beans grown in South America are better suited to harder water. Therefore, water hardness should be selected higher for coffee beans grown in this region.

It can be said that coffee beans grown in Africa are better suited to softer waters.

For this reason, the hardness of the water for coffee beans grown in this region should be kept lower and bicarbonates should be more dominant.

In order to determine with exact results which salts dissolve better for which coffee regions, first the mineral content of the region where the coffee beans to be used are grown should be analyzed. Then the relationship between the characteristics of the coffee beans grown in this region and the mineral content of the water is examined. As a result of these analyses, it is determined which salts dissolve better for which coffee regions. For example; in regions where coffee beans have low magnesium levels, magnesium-containing salts can dissolve better. As a result, which salts dissolve better for which coffee regions vary depending on the relationship between the mineral content of the region where the coffee beans are grown and the mineral content of the water. However, since it is difficult to conduct these field-based analyses, we professional coffee lovers, apart from the basic distinction made above for African and American regions, can come up with a recipe for the most optimum and impressive extracts by relying heavily on our sensory analyses, as we do in every subject.

As we have shown in previous blog posts, sensory analysis has begun to find an important place in such scientific studies, thanks to panels of experts, as well as analytical and instrumental analysis.

Although the subject of quality coffee is still a new concept, our FINAL TOUCH product, which emerged as a result of our R&D work, will allow you to make the final touch in reaching the best coffee for professional baristas who are devoted to this work and aim to achieve better, coffee shops that cannot obtain the expensive filter systems mentioned in our article for any reason, and home baristas who want to transform themselves from a good coffee drinker to a good brewer.

Have fun brewing!

You can have the perfect water you need for your coffee by trying the recipes we have created below or your own recipes.

​

*Add the number of drops listed in the prescription to your 450 ml of water;

​

For Filter Coffee

​

SWEETNESS and BALANCE ( 100 ppm )

4 drops / Magnesium 4 drops / Calcium 2 drops / Potassium 1 drop / Sodium

CLEAN and BRIGHT ( 78 ppm )

3 drops / Sodium 3 drops / Potassium 1 drop / Calcium

BODY and BALANCE ( 94 ppm )

7 drops / Magnesium 2 drops / Calcium 1 drop / Potassium

*** Recipes with Uludağ Premium (33 ppm) water

has been prepared.

*** Shake the bottles before use.

*** Store bottles at room temperature and in the dark.