I have a pH meter to measure my mash.
Here were the results from today (all measured at ~room temp):
5 min: pH = 5.34
45 min: pH = 5.42
1st batch sparge pH: 5.45
2nd batch sparge pH: 5.51
All perfectly normal, including the rise over 40 minutes. This is one of the things that makes accurate prediction of mash pH difficult. OTOH it improves the accuracy of spreadsheets that predict pH on the high side. Just wait a few minutes and you may get to the spreadsheet's prediction though it seems to me, as you have experienced, that they tend to estimate low.
I had the sodium bicarb with me just in case the pH dropped too much.
The probability is higher that acid would have beer required so when you do a recipe for the first time you should have that on hand too.
I guess my biggest concern was if my beer flavor was going to lack anything without any addition of the carbonates (bicarbonates), or sodium.
Put some bicarbonate in a glass of water and taste it. Is that a flavor you want in your beer? This demonstration is overly dramatic as most of the biarb is converted to carbonic and in a beer with pH 4.5 carbonated to about 2 volumes there will be about 84 mg/L bicarbonate from the gas. Most of the damage from bicarbonate comes from its pH increasing effect in the mash.
Or, am I just confused and the Alkalinity and RA values are just numbers that help me achieve the correct pH of my mash only and really do not contribute to flavor??
There are 2 concerns with brewing water chemistry sorted into their direct and indirect effects on beer flavor. You can't completely separate them but calcium is pretty flavor neutral while it does have an effect on mash pH though a small one relative to acids. Bicarbonate, carbonate and hydroxyl ions all have an effect on mash pH and while they all have negative flavors associated with them if you do anything like a decent job at getting mash pH correct, even though it may involve adding some of those ions to do so, they will be neutralized. Correct mash pH is a sine qua non. Do it right and your beers will bloom in flavor. Botch it and they will be dull, flat, insipid if pH is too high. If pH is below the recommended 5.2 or so there is debate about the flavor effects with some apparently liking them and others not as I noted in my earlier post. The first goal in any beer is to get mash pH correct for the indirect flavor effects.
The direct flavor effects are more familiar as they are like adding salt in cooking. Chloride sweetens and rounds , sodium sours and renders things salty, potassium does the same, sulfate has a great influence on hops aroma and bitterness perception. Mgnesium influences mash pH but to a lesser extent than calcium so it is an indirect ion but it also produces a bitter, sour flavor and is thus generally to be avoided as is sodium unless you want those flavors and some beer styles call for them (Gose).
This means that salts like sodium chloride are a mixed blessing as chloride has a direct positive flavor effect while sodium has a negative one. Sodium perception kicks in later than chloride so lots of brewers add some sodium chloride to the extent they get the sweetness of the sodium but not the mawkish, sour taste that comes from sodium. Some use potassium chloride because it takes more potassium than sodium to get those saline effects.
Sodium bicarbonate and sodium carbonate both have powerful pH controlling effects. Sometimes you need to raise pH as when you brew a beer with lots of acid bearing malts. If you use either of these to set proper mash pH the bicarbonate and carbonate will be gone but the sodium remains. If it is below the levels where it effects taste then these can be effective means of managing mash pH. If, conversely, your starting water is high in sodium the amount added could push you over. Calcium carbonate would be preferred because calcium is generally beneficial (in ways beyond pH control). The point of all this being that it can be quite complicated so if you are really interested you'll find lots with which to occupy yourself.
I really haven't gotten a hold on the RA value compared with styles of beers yet.
Don't put too much reliance on RA. It was conceived as a means of comparing water samples in terms of their suitability for brewing the typical lagers of German brewing. You can get the story from the horse's mouth at
http://www.wetnewf.org/pdfs/Brewing_articles/KolbachPaper.pdf and there is a graphic representation of the RA's of various brewing cities at
http://www.wetnewf.org/pdfs/kolbach-ra.html. It's a useful concept but home brewers tend to try to make it do things it was not intended for. The main point is that there is no requisite RA for a particular beer.
