Brew Day! Always a good day- mashed in added my salts and lactic acid- doughed in and stirred for ~5 min. Took a sample and set on the kitchen counter. Went back out side and got side tracked. Went in, calibrated pH meter and took pH reading around 30min mark into 60 min mash. PH was 5.15 at room temp 74.(my meter also has temp adjustment). My target was between 5.2/5.3. This is a west coast style IPA so im bot super worried just curious what i can expect.
Myself I would probably do nothing. If you were that worried about it toss in what ever amount of baking soda brunwater recommends for a 0.5-1.0 higher pH.
5.15 rounds to 5.2. Bru’n Water rounds the same way. If you find that Bru’n Water systematically overestimates the pH then you may want to take that into account, but for now I wouldn’t change anything.
One thing to remember is that auto temp correction in a pH meter only adjusts for the electrical response of the probe at a temperature other than what it is calibrated for (20C usually). There is another, bigger difference which is that the mash pH actually changes; as temperature goes up, more hydrogen ions dissociate and the pH decreases.
The reference temperature of 5.2 is usually quoted at mash temperature, and would be closer to 5.5 at room temp. The range for conversion is pretty big, so I wouldn’t sweat it. Your pH is lower than I go for an IPA, but I’ve never tried it.