That discusses the buffer processes in blood ph.
If a temporary rise or fall is all you're after, you could either go do a strenuous workout (which would quickly acidify blood thanks to lactic acid release) or eat a cucumber salad (which has a high alkalizing effect).
Blood ph takes weeks to alter to any significant degree, saliva/localized organ ph, interstital fluid, etc. can change faster.
Here's a study on baking soda and kidney disease, because the kidneys are part of the blood ph regulation mechanism, something is altering outcomes.