Advanced Coffee Making

0 of 81 lessons complete (0%)


ACM 3.11 – Milk as a Bypass

TDS for Milk Drinks

You can edit this version of the Cowculator (above) right here on the BH website. Edit blue numbers only. 

The Cowculator is a sophisticated dilution calculator for milk beverages, taking into account the main ingredients of milk and coffee, and displaying their concentrations after everything has been mixed. It’s the third sheet in our Toolkit (sheets can be navigated via the tabs at the bottom of the screen).

Milk is about 87% water and that’ll also have an effect on the acidity of your coffee. Milk is actually mildly acidic with a pH of between 6.5–6.7 due to its lactic acid content. This makes it 100 times less acidic than espresso, which has a pH of between 4.5–5. The pH scale is a logarithmic scale where each whole number (integer) represents a factor of 10 times the previous number — i.e., pH5 = pH4 x 10

Referring to the BH Cowculator, it is easy to see the dilution effect of milk sugar (lactose) which averages around 4.8% in whole milk, adds much more saccharides by mass to a flat white coffee than the sugars in the espresso.

As mentioned in the previous lesson, the fat in milk will reduce our palate’s ability to detect bitterness in coffee. This sounds negative but of course, lovely creamy flat whites taste incredible. Understanding how milk fat percentages affect the flavour of your coffee is a very important part of a milk coffee’s ‘TDS’. As there are no hard and fast rules, we highly recommend collecting various kinds of milk available to you and tasting them side by side with coffee, but without labels.

A note on pH:

A small portion of the water in any solution is always split from H2O into H+ and OH- ions. In pure water, the concentration of each is 1×10^-7 M (0.0000001 mol/L) and they balance each other out, to make a neutral solution.

If you add an acid or a base,