I Have tried to alkalize my cocoa nibs by briefly dipping them in a solution of water and sodium carbonate. I was amazed by the change of color to a real dark brown. Only that I lost a lot of the cocoa flavor. But that bitter taste too disappeared. My question is:
Is that a proper way of making an alkali solution? If not, what is the right way? Am I not risking too much by adding water because of the seizing challenges? Will I get the same results(Darkening and reducing acidity) if I mix the carbonate powder in the liquor with the other ingredients?
Yes that is a way to alkalize or dutch your cocoa nibs and yes, you lose a LOT of flavor. It's one reason I have little experience in it as I never liked the results.
I can't answer if you made your alkali solution correct as you didn't tell me how you made it. Only what you made it out of. To that regard, yes, sodium carbonate (baking soda) is the correct chemical.
As far as what the industry does, nibs are not normally alkalized as only the surface is then treated. The interior is hardly affected. The powder is what is treated. It's mixed in a slurry (after the butter is pressed out) and then dried.
And yes, it will also work to add your baking soda direct to the liquor. It's what I've done. About 1 t per pound. With a radical drop in flavor. It basically made it one dimensional in flavor. I much prefer to simply not use beans that are overly bitter or astringent so alkalization is not needed. And as for acidity reduction, I prefer roasting and refining techniques to reduce that instead of neutralization by chemical techniques.
With this question in mind, I tried dutching some Peru nibs that I had roasted. I mixed up a 10% solution of baking soda and soaked the nibs for about 1 hour. I then sun dried them. As expected they turned very dark. And the chocolate aroma was radically reduced. The flavor did turn a little more chocolatey, but it is difficult to tell if it was real or only perception as the bright, tangy fruit disappeared. What I was left with was a non-bitter, non-fruity, non-offensive (not that it was offensive) cocoa nib that basically was BORING. The resulting chocolate was the same. Non-bitter, non-offensive, non-fruit and BORING.
In general, my take is this. Alkalization was introduced as a way to make poor beans palatable. Maybe a partial treatment might have a place in artisan, single origin chocolate, but to my mind, I don’t find a strong reason to treat your high quality, single origin cocoa.