Our latest brew day was for our Mr Rice Guy - Japanese Rice Lager recipe. Here's how it went
We started off in the usual fashion with collecting our water. 21L of strike water to begin with and 12L of sparge water (recipe calls for 9 but we always have a bit extra just in case)
We made our water chemistry adjustments with additions of calcium chloride, calcium sulfate and magnesium sulfate
We also adjusted the strike and sparge water using phosphoric acid - sparge water adjusted to 5.43 - well within the generally recommended 5.2 - 5.6 range.
Laying out our ingredients - 3kg of pilsner malt and 1.5kg of flaked rice
With a relatively light grain bill of only 4.5kg all up, mashing in was pretty easy - we added the flaked rice after adding the pilsner malt
When we were researching this recipe, we came across a few people who mentioned that flaked rice can make for a really thick mash - and they weren't kidding. Not sure if it was just the rice or if the KegLand grain crush was a bit finer than what we normally get from our other local homebrew shop, but this mash was
hard work.
After mashing in we mixed everything and left the grain bed to settle for 10 minutes before taking a pH reading - 5.42. Recipe estimated 5.32, so this was a bit higher but still acceptable.
We then began recirculating the wort - we couldn't lower the recirculation speed any lower, and even still we weren't getting any flow back through the grain bed so there was plenty of manual stirring going on.
We opted for a different mash schedule that we hadn't used before, with a 30 minute rest at 63°C followed by a 30 minute rest at 70°C. This should help promote plenty of conversion of sugars and a highly fermentable wort with a low finishing gravity
It took a good 10-15 minutes to raise the temperature up to 70°C for the second mash step but we got there.
Even at this higher temperature, recirculation was painfully slow, even after adding loads of rice hulls.
The sparge was also slow, with plenty of stirring required to coax the sparge water back through the grain bed. After completing the sparge, we took a gravity reading and ended up with 1.041 - a couple of points above our predicted gravity, and as it turns out, this reading was actually low (after determining our original gravity post-boil)
While waiting for the boil, we began measuring out our first hop addition of Hallertau Tradition hops
We also decided to take a pre-boil pH reading which gave us a surprisingly high 5.59. Very strange that this somehow ended up higher than it was at the start of the mash, perhaps our sparge water wasn't as low as we thought and it raised the pH somehow? Our pH meter was calibrated right before we started brewing so we're a bit perplexed by this.
We added another 1mL of phosphoric acid which dropped the pH back down to 5.49. We probably should have tried to go a bit lower but we're always nervous about overshooting and getting the pH too low.
Rolling boil underway - plenty of hot break forming on top.
We added our hops at 60 minutes and 10 minutes, and also added yeast nutrient and whirlfloc with 10 minutes remaining in the boil
Post-boil, original gravity of 1.046 - quite a few points higher than expected
And after taking a floating hydrometer sample, it looks like the gravity was closer to 1.050! Looks like our digital refractometer may be reading a little low.
We didn't take a photo of it, but our post-boil pH was higher again, at around 5.7! Totally confusing as it's generally expected that the pH will drop a couple of points during the boil, not climb higher. We're hoping it's some kind of equipment error, or perhaps there was something wrong with the sample we took. We did some reading that suggested the sample should be taken once the wort has cooled so the calcium can drop out of it, so we may try this next time (though we did cool our sample in an ice bath before taking the pH reading).
One of our favourite things about brewing in winter is the cold ground water that makes post-boil chilling so much faster. The cold break looks pretty cool too when chilling
Finally we transferred to our Keg King Apollo Titan fermenter at around 25°C and left it to cool in our fermentation fridge overnight to ~12°C before pitching 2 packets of W34-70 dry yeast.
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