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* Sodium Hydroxide, NaOH. Available in liquid or powder form. Be sure to note its molarity (M), units of mol/L. For more info on mol, see [https://en.wikipedia.org/wiki/Mole_(unit) here].
:*<code>'''Safety caution''': always wear safety glasses and gloves when handling NaOH in any concentration. NaOH can cause severe burns. In concentrations higher than 0.1, NaOH can corrode through clothing. See [https://www.ccohs.ca/oshanswers/chemicals/chem_profiles/sodium_hydroxide.html Canadian Centre for Occupational Health and Safety on Sodium Hydroxide].</code> :*Note that bottles of NaOH should be capped so as to avoid as much exposure to the air as possible. This is because NaOH reacts with CO<sub>2</sub> in the air, causing the NaOH to become inaccurate over time as a base titration <ref>[https://www.sciencedirect.com/science/article/pii/S2405656116300578 A novel rate of the reaction between NaOH with CO<sub>2</sub> at low temperature in spray dryer. Yadollah Tavan, Seyyed Hossein Hosseini. 2017. DOI: https://doi.org/10.1016/j.petlm.2016.11.006.]</ref><ref>[https://www.chem.indiana.edu/wp-content/uploads/2017/11/17-3-Sodium-Hydroxide-and-Carbon-Dioxide.doc "Sodium Hydroxide and Carbon Dioxide: Why it is Important to Keep Your Standard NaOH Solutions Capped". Indiana University course material. Retrieved 10/18/2018.]</ref><ref>[https://www.homebrewersassociation.org/how-to-brew/resources/conference-seminars Robert Hall. The "Sour" in Sour Beers: Microbiology Sensory Perception and Styles. HomebrewCon 2018 Seminar. 2018.]</ref> (~42:00 mins in).
* Nitrile or latex gloves. NaOH is a strong base, it will hurt you if you get any on your skin.
At or around a pH of 8.2, we have reached our equivalence point for a titration of pure NaOH and pure lactic acid. We need to convert the moles of NaOH we added into moles of lactic acid, and then divide the equivalent grams of lactic acid by the original volume of beer. That gets us g/L, and our titratable acidity. For a numerical example, assume '''15mL''' beer with a gravity of '''1.015''', '''5mL''' 0.1M NaOH:
[[File:TA example.gif|center|Titratable Acidity Example]]
In summary, the measurement of titratable acidity is a technique to quantify the total acid level of a beer. A major assumption was made: all the acid in the liquid was lactic acid. Two beers could have the same TA measurement, but have differing levels of palatable acidity, due to the acid makeup of the beer.
==Limitations of TA==
Although a better representation of perceived acidity than pH, titratable acidity might have has some limitations on accurately measuring perceived acidity in beer. [[Omega_Yeast_Labs|Omega Yeast]] performed [https://topcrop.co/dialing-in-sourness-ph-vs-ta an experiment] to compare pH and TA. While TA represented sensory test results of which samples were more sour than others in many cases, there were some exceptions. For example, beers dosed with the same amount of acetic acid versus lactic acid measured the same TA, but the acetic acid sample measured higher in sour flavor in the sensory test. Different types of beers dosed with the same amount of acid measured the same TA, but they had different sourness levels in the sensory test. Also, beers dosed with double the amount of acid did not necessarily taste twice as sour, meaning that the taste of sourness is not linear with higher TA levels. Omega Yeast concluded that the types of acids can greatly impact the sensory experience of sourness, as well as the base beer. While TA can be a good indicator of sourness, it still cannot replace the human organoleptic system. See also:* [https://topcrop.co/dialing-in-sourness-ph-vs-ta "Dialing in Sourness: pH vs TA" by Laura Burns and Shana Solarte.]* [https://www.facebook.com/groups/MilkTheFunk/permalink/1481798761848333/ this MTF discussionon TA] for details.
==Lactic Acid Test==
* [http://sourbeerblog.com/a-guide-to-blending-sour-beer-with-fruit/ "A Guide to Blending Sour Beer With Fruit" by Matt Miller; includes ABV and TA calculators for fruit additions.]
* [https://www.beyersanalytical.com/redcheck RedCheck Titratable Acidity kit.] <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1934289469932591/?comment_id=1944943422200529&reply_comment_id=1945120492182822&comment_tracking=%7B%22tn%22%3A%22R1%22%7D Kelley Freeman. Milk The Funk Facebook group thread on TA kits. 01/06/2018.]</ref>
* [https://www.lallemandbrewing.com/en/canada/brewers-corner/brewing-tools/measuring-titratable-acidity Lallemand Brewing online TA tool and instructions using ASBC methods.]
* [https://blueowlbrewing.com/2017/06/20/what-is-a-sour-unit Blue Owl Brewing uses an altered TA number called "Sour Units" to communicate to customers how acidity their beers are.]
==Authorship==