Discussion on Coffee Water quality: what does coffee tds mean? coffee water quality tds

Professional coffee knowledge exchange more coffee bean information please follow the coffee workshop (Wechat official account cafe_style)

Black coffee as a drink, the soluble matter accounts for about 1.0-1.5% of a cup of coffee, in other words, 98-99% of a cup of coffee is water. The water we choose will affect not only the extraction process, but also the final performance of coffee in the cup. And the taste of water is also part of the taste of coffee. Therefore, it is very important to choose the right water for cooking.

However, for many people, the choice of cooking water is often easy to overlook. Clean, clear, transparent, odorless healthy drinking water is the most basic requirement.

The first major factor affecting water quality

Total soluble solids TDS

When discussing water quality, we will inevitably mention a concept: the abbreviation for the total amount of soluble solids is TDS, that is, the total amount of soluble matter dissolved in water. This can be measured with a water quality testing pen, or tds pen, which can be bought online for dozens of yuan. It is measured in milligrams per liter, which is usually expressed in ppm, and their values are the same.

The higher the ppm value, the more soluble matter in the water and the lower the extraction rate. On the contrary, the higher the extraction rate will be. The tds we choose to boil water is generally suitable in the range of 80-180ppm.

Let's use a few common water examples. For example, ice dew belongs to mineral water, which is made of pure water by artificially adding trace minerals, about 20-30ppm.

IMG_4973

Natural mineral water such as Nongfu Spring is about 60-80ppm. You can check the label of the bottle. The general brand of water tds will show a general range. Because the water source is different, or the batches are different, the tds will fluctuate in the range of the table note, and the actual measured value should prevail.

In general, natural mineral water contains more trace minerals, more abundant, and the price will be relatively higher, such as Evian at 300-400ppm or higher, which means it contains more trace elements, but it does not mean it is more suitable for coffee brewing. Usually when the tds of the water reaches about 300ppm, you can drink more obvious mineral flavors, such as astringency, weak saltiness and even weak bitterness.

IMG_4974

Generally speaking, pure water and distilled water like Ipoh or Watsons have single-digit tds values, and the coffee produced will be sour, light in taste, and even easy to bring out a little smell. So pure water is not a good choice either. But we can use pure water and mineral water with high tds within the range of our ideal TDS as cooking water.

Different water, even if the TDS value is the same, but it contains different soluble solids, which will also affect the final flavor of coffee. In addition to affecting the efficiency of coffee extraction, ions such as calcium, magnesium, sodium and potassium have a weak taste in water. For example, some water, although the tds value is not high, but there are more potassium and sodium ions, the salty coffee will be strong.

Our most common tap water, which is sterilized, contains residual hypochlorite and may contain very small amounts of heavy metal ions such as iron, which can damage the flavor of coffee. Tap water is not a good choice. If there is only tap water to choose from, we can boil the water first, open the kettle lid and let it boil again for a while before using it.