So, I’ve had a chance to evaluate my split batch kolsch yeast comparison.
I brewed 38L (10gal) of a simple kolsch - 97% pils malt, 3% wheat, 1.048, 24 IBU magnum at 60 mins. The wort was split evenly between 2 fermenters, one got WY2565 from a 2L (decanted) starter, the other got a pack of rehydrated Lallemand Koln yeast.
They were pitched at 14°C (57F) and received 2 mins of oxygen.
The 2565 kicked off with visible krausen at around 12 hours, the Koln took a good 36 hours to show similar activity. (in retrospect, was under pitched a wee bit).
Both beers were slowly ramped up from around day 5, and both finished out at 1.011.
They were then cold crashed and fined with gelatine.
Closed transfers to purged kegs, carbonated and ready for initial tasting at 4 weeks.
2565 on the left, up to its old tricks, refusing to clear.
On initial tasting at two weeks post kegging, I was reasonably easily able to tell them apart on triangle testing, the Koln was a little sharper/crisper and had less ‘kolschy-ness’. I preferred the 2565. It reminds me of Paffgen kolsch, the Koln strain seemed cleaner, more like Fruh.
At 4 weeks post kegging, the beers were much harder to differentiate, there was still a clarity difference but it was less obvious, and I failed as many triangle tests as I passed. My wife failed 4 out of 4 triangle tests at both 2 and 4 weeks. (Interestingly, both kids picked it on aroma alone)
The second usage of the Koln strain was to try to make use of its purported biotransformation skills. I brewed a NEIPA with a recipe I had used several times in the past with different yeast strains. I used the somewhat unoriginal but delicious citra/mosaic/galaxy combo.
It came out really well, deep saturated citrus hop character, possibly the best one I’ve made so far. Its now been in the keg for 2 weeks and is still hazy and very enjoyable.
