I'll be brewing with MaltGems tomorrow, starting out simple and basic: a Blonde Ale using 89% base grain with the remainder split equally with carapils and 20L crystal.
Quoting and updating myself: yesterday's brew session didn't go as smoothly as I had hoped. Like a Charles Dickens novel, "It was the best of times, it was the worst of times."
The "best": the spreadsheet I built to accurately track and predict wort volumes through every stage from mash-in to boil to final volume into the fermenter worked beyond my wildest expectations, accurately predicting to the nearest tenth of a liter and converting it to gallons, so I've finally got that phase dialed in to my equipment profile. Before I'd only had a rough estimate and never really knew what volume was in the fermenter since I pump from the kettle into a sealed stainless steel conical (no sight glass, pressure vessel). My predicted O.G was 1.043, Actual was 1.042. Predicted volume was 7.31 gallons, Actual was 7.3 gallons. The biggest surprise was
where the losses were occurring, as well as where they were
not.
The "Worst:" the mash was a physical and logistical nightmare. About half way through the Beta amylase step I started hearing a splashing noise underneath the mash cap. Bad sign. The way my Braumeister works is a malt pipe (open cylinder) is placed into the kettle with screens on the bottom and on the top with the grist inside the malt pipe. The screens keep the grain contained. The strike water is added (under letted) into the kettle. Water flows into the grain bed through the bottom screen and into the surrounding area between the outside of the malt pipe and the interior wall of the kettle. The electric heating elements are located at the bottom of the kettle, outside of the bottom of the malt pipe. An internal pump draws heated water from around the heating elements and then introduces it to the void underneath the bottom screen of the malt pipe. So circulating wort flows up through the grain bed and out through the top screen to cascade down to the heating elements to be pumped through the grain once again at the programmed temperature.
It's an extremely efficient mash process with numbers regularly in the high 88% range, even without sparging. Over the years I've figured the best gap setting for my grain mill is 1.6 mm, fine enough to achieve these numbers without causing stuck flow. It looks like the MaltGems is significantly smaller than this. My concern with this grain was keeping it contained and not passing through the screens. I focused on the wrong thing. The grain bed had gotten compacted to such an extent that it had blocked the flow through the screens. The wort was being forced between the seal at the top of the malt pipe and the top screen causing extreme fountaining and horizontal geysers. Tiny grain bits were everywhere inside and outside the malt pipe. I quickly suspended the mash to assess the damage. It soon became apparent that the only course of action was to drain the kettle, get the grains out of the malt pipe, clean everything, and start over where the mash had been suspended.
Thank goodness I never got rid of all the old brew buckets that have been collecting dust and taking up space for the last several years. Clean, sanitize, rinse, repeat. Literally. Obviously my best laid plans for LoDO were out the window. So I cleaned up all the old gear, got the wort into two plastic buckets and the grains into another. Then I had to clean the Braumeister, malt pipe, screens, etc. I also had to disassemble and clean the pump and the plumbing between the kettle wall and the bottom screen which had gotten crammed full with grist. I feel lucky that I didn't burn up the pump. All this work is tedious enough on a
good day, let alone
twice along with all the old plastic stuff. Finally after scrubbing and sanitizing and reassembling everything it was time to get the grains back into the malt pipe. Fortunately I had a partial bag of rice hulls on hand to help loosen up the grist a bit, so I chucked in about 4 hands-full where I would have normally put in one or two at most. It partially filled the void left by the 1~1.5 pounds of grain that I wasn't able to salvage. Then I poured the wort into the repacked grain bed, thinking that the bed would filter the massive amount of grain that was still in the wort and trap it in the malt pipe. That actually worked very nicely, so now with the top filter screen in place and mostly grain-free wort in the kettle, I took a deep breath and restarted the mash.
After a few minutes of recirculation I began to get some return of the fountaining, but greatly reduced from before. There was some minor splashing which is bad for LoDO, but was within acceptable limits otherwise, so apparently the rice hulls were doing their job. For the most part the grains were staying inside the malt pipe and not getting blown out into the space between the malt pipe and the heating element/pump inlet. This whole fiasco cost me a two-hour extension to my brew day and a stiff back this morning.
Now the followup: After the boil was complete I chilled and whirlpooled as per normal. After settling and before transferring to the fermenter I sneaked a peek at the wort. I usually transfer "blind" to limit O2 exposure, but since that ship had already sailed I raised the lid and found 7+ gallons of the
clearest wort I have ever produced. Normally I would transfer directly into the fermenter, chill down to pitching temperature, and perform a mini-trub dump of the kettle tailings that got pumped over. After three hours of chilling and settling in the fermenter, the sight glass was still clear. Usually I'll get a liter or two of murky gunk/hops/grain bits. This time, Nada. So I pitched a 1 liter starter of krausening Imperial A09 "Pub" yeast (shameless plug for JayBird's 3" Sight Glass Yeast Brink), hit it with 90 seconds of O2 through the carb stone, set the temperature to 67F, and pulled the tap on a cold pint of my Red Ale, affectionately known as
"Irish Foreplay." This morning, after extracting my sore back from bed, I was rewarded with the sight of bubbles actively escaping from the blow-off line into a Mason jar of StarSan solution.
"I made BEER!!"
TL;DR
So, the jury's still out, and will be for the next few weeks, to see how this will all turn out. The lack of adherence to LoDO techniques will shorten the shelf life along with other subtle degradations, but it's a Blonde Ale and it's still summertime and it's a simple beer and it'll go fast. So there's that. I hit all my brew day targets with high accuracy, though given the nature of the husk-free grain the O.G. should have been significantly higher when using "standard" guidelines for predicting "normal" malts. I hit every one of my pH marks from mash-in to post boil, so there shouldn't be any additional astringency due to the extended mashing and handling exposure. The color is very pale which is to be expected from a 90% 1.8L pilsner malt with only 10% additional grist of carapils and 20L crystal malt. Despite the pain and aggravation of yesterday's brew session, I have high hopes and expectations for this beer, and by extension this malt. In the future I'll definitely limit it to 50% or less of the grain bill and add copious amounts of rice hulls until I can get a handle on the crush size and how best to use it in my equipment.
Cheers!