Question

If you measure a tds of 1.4%, and you used a brew ratio of 15, what is the percent extraction?

Answer 1

The percent extraction, also known as percent yield, of coffee in brewing can be calculated from the TDS and brew ratio. In this case, using the values given, the percent extraction is 21%, which is within the ideal range of 18-22% for coffee brewing.

Step-by-step explanation:

To find the percent extraction of coffee during brewing, we use the formula:

1. Identify the given information:
   - Total Dissolved Solids (TDS) = 1.4% (which is the concentration of coffee in the water),
   - Brew ratio = 15 (which represents the ratio of water to coffee).
2. Calculate the percent extraction using the formula:
   % Extraction = (Brew ratio × TDS) / 100
3. Plug in the values and calculate:
   % Extraction = (15 × 1.4) / 100 = 0.21 or 21%

The percent extraction represents how much of the coffee was extracted into the water. An extraction rate of 18-22% is generally considered ideal for coffee brewing, which means the extraction in this scenario is within the typical desirable range.

Answer 2

Answer: the extraction is 18.2%.

Step-by-step explanation:

Let's see few definitions:
TDS = Total Dissolved Solids = solids dissolved in the brew
PE = Percent Extraction = percent of solids extracted from the dry coffee grounds

The percent extraction can be calculated by the formula:
PE = TDS × Rm

where
Rm = ratio between the mass of the brew and the mass of dry grounds

Now, you need to consider the following facts:
1) every 1g of coffee absorbs 2g of water
2) the given brew ratio is 1:15, which means that for every 1g of grounds we use 15g of water

Let's call
x = grams of coffee grounds we want to use
Therefore the mass of the brew will be:
m(brew) = water we use - water absorbed by the coffee
= 15·x - 2·x
= 13·x

Therefore,
Rm = m(brew) / x
= 13·x / x
= 13

Hence, the percent of extraction will be:
PE = TDS × Rm
= 1.4 × 13
= 18.2