Carbonation in Lambic: Difference between revisions

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at a ratio of about one H<sub>2</sub>CO<sub>3</sub> molecule per 590 dissolved CO<sub>2</sub> molecules [REF, CRC handbook?]. Carbonic acid has pKas of ~3.49 and ~10.32 [PINES 2016], which are defined as:
at a ratio of about one H<sub>2</sub>CO<sub>3</sub> molecule per 590 dissolved CO<sub>2</sub> molecules [REF, CRC handbook?]. Carbonic acid has pKas of ~3.49 and ~10.32 [PINES 2016], which are defined as:


Ka<sub>1</sub> = [H<sup>>+</sup>][HCO<sub>3</sub><sup>-</sup>]/[H<sub>2</sub>CO<sub>3</sub>]
Ka<sub>1</sub> = [H<sup>+</sup>][HCO<sub>3</sub><sup>-</sup>]/[H<sub>2</sub>CO<sub>3</sub>]
Ka<sub>2</sub> = [H<sup>+</sup>][CO<sub>3</sub><sup>2-</sup>]/[HCO<sub>3</sub><sup>-</sup>],
Ka<sub>2</sub> = [H<sup>+</sup>][CO<sub>3</sub><sup>2-</sup>]/[HCO<sub>3</sub><sup>-</sup>],


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Note that the denominator is the total concentration of CO<sub>2</sub> and products to an approximation better than one part in two million. Combining this with the total carbon from above and re-arranging, we can write
Note that the denominator is the total concentration of CO<sub>2</sub> and products to an approximation better than one part in two million. Combining this with the total carbon from above and re-arranging, we can write


[CO<sub>2</sub> (aq)] = (4.3*10^-2(pH+1))V_CO<sub>2</sub>/((1+Ka_0)*10^-2pH + Ka_0 * Ka_1 * 10^-pH + Ka_0 * Ka_1 * Ka_2)
[CO<sub>2</sub> (aq)] = (4.3*10<sup>-2</sup>(pH + 1))V<sub>CO<sub>2</sub></sub>/((1+Ka_0)*10^-2pH + Ka_0 * Ka_1 * 10^-pH + Ka_0 * Ka_1 * Ka_2)
[H2CO3] = Ka_0 * [CO<sub>2</sub> (aq)]
[H2CO3] = Ka_0 * [CO<sub>2</sub> (aq)]
[HCO3 -] = Ka_1 * [H2CO3] * 10^-pH
[HCO3 -] = Ka_1 * [H2CO3] * 10^-pH
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N.B. these calculations were performed assuming a temperature of near enough to 25C to make no meaningful difference, and no account was taken for ionic strength, etc.
N.B. these calculations were performed assuming a temperature of near enough to 25C to make no meaningful difference, and no account was taken for ionic strength, etc.


==The effects of Carbonation on Mouthfeel and Physiology==
==The effects of Carbonation on Mouthfeel and Physiology==