Spent grain + Agave syrup

[ckdistills]

Here's a recipe I just fermented - looking forward to how it turns out. A fermentation buddy got a lot of light blue agave syrup that's past the 'best by' date free on Craigslist. We've been tossing around ideas for what to do with it the last year plus, I haven't been super into a straight agave spirit given that it's light syrup and not nectar. I finally had the idea to use it as a sugar head after an all grain and figured that the grain and yeast bed would help mitigate stuck fermentations that seems common with agave given its high fructose content. It did - this fermented fast!

I had just finished a ~2/3 recipe of CROW (33 lbs corn, 6 lbs red wheat malt, 6 lbs white wheat malt, 6 lbs rye malt, 2 lbs toasted oats). I ferment on the grain and use a brew in a bag technique to drain/squeeze the liquid. Bag with spent grain went into a trash bag and then into the fridge to keep it from molding until ready to reuse. After racking the liquid out of the fermenter, leave the sludgy yeast bed with enough wash to keep covered. Pull out a quart of spent yeast sludge, add some water, backset, or wash and boil it as yeast nutrient.

Onto the yeast bed:
3.5 gallons of backset from the all-grain stripping runs
4 gallons of light Agave syrup
10 gallons hot water - stir to dissolve the Agave
6 gallons cold water to cool the wash
Drop in bag of spent grain + any accumulated liquid from the trash bag
Couple handfuls of oyster shells
Boiled yeast slurry

There was more sludgy yeast bed & leftover wash than I thought in the bottom of the fermenter, 32 gallon fermenter was as full as it's ever been. Grain cap at the top of the fermenter. Next time 5 gallons less.

SG 1.065.

Went out to dinner while waiting for the temp to drop to pitching temp. Came back to a very active ferment, the FermPro 921 from the all grain ferment going strong. Pitched 30g of EC1118.

FG 0.996 - 3 days later.

The ferment has the same grain smell as the original, but much less intense. It's a bit sour and otherwise I can't really pick out the agave flavor.

Next up: pulling the grain tomorrow and starting to strip over the next week or so. More to come.

I've got a lot more of this syrup so if this turns out I plan on doing an agave sugared after every all grain.


Edit: @Mods - I meant to post this in the Sugar wash section. Happy to have it moved there!