Lesson 5 - The Mashing Process SAQ

 ** You are brewing a beer using isothermal mashing, and you need the mash to be 66°C. From the data in the table below, what should the strike temperature be, and what is the percentage fermentability of the wort produced?

Response:

Our equation for calculating mash temperature from the temperatures and amounts of mashing water and grist is as follows:

Where:

We can rearrange this to make the mashing water the subject:

Inputting the figures from the table gives us:

And calculating out the brackets gives us:

We can check we are correct by entering our water temperature into the original equation:

To work out the fermentability, we need to calculate the apparent attenuation using this equation:

So if we enter our numbers from the table, we get:

And to convert the apparent attenuation to the real attenuation, we multiply by a factor that accounts for the effect of ethanol on the gravity: