[[File:TA Formula.gif|center|Titratable Acidity Example]]
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 as a base titration overtime <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).
===Example===