During our Feb 2018 meetup Pen and Mike shared their five way split experiment which was to try different yeasts in a (semi-)controlled environment. We particularly enjoyed the blind tasting challenge. Thanks for sharing.
Here's a copy of the details supplied on the day.
Simply Pale Ale from Richies
Not much information on the packet. No O.G., ingredients list, colour, bitterness or yeast name.
Previous brewers indicated O.G. of 1.040 and F.G. of 1.006. (4.5% ABV and 85% AA).
Keep everything as identical as possible until the pitching of the yeast and to use the supplied yeast as the control. Dry yeast only.
Followed the kit's instructions and made up a 22.5L batch. No water treatment, hops or additions of any kind. Took the O.G. reading.
Took five food safe 6L buckets, calibrated them to 4.5L and syphoned 4.5L of wort into each.
Reactivated each yeast with 6g of Go-Ferm Protect in 50ml of water at 35C for 15 minutes.
Pitched 1tsp(??) of each yeast into each bucket, partially sealed each and left to ferment. One was a lager yeast so that was moved to a cooler environment. Using a full 11g packet seems like a significant over pitch and calculations indicated only about 4-5g was required.
Kit Supplied: No information available.
The assumption was made that this was (like) a standard Safale S04 English Ale yeast so we avoided picking similar yeasts.
Mangrove Jack Bavarian Wheat Yeast M20: 70-75% AA, Low Flocculation
“Deliciously smooth, light golden in colour, full bodied aromas of vanilla and banana and a lingering aftertaste. This yeast produces a silky mouth feel and rich body. Suitable for brewing Hefeweizen, Kristal Weizen, Dunkel Weizen and more.”
Fermentis Safbrew T-58: 85% AA, Low Flocculation
“Develops estery and somewhat peppery spiceyness.”
Lallemand Belle Saison: 85% AA, Low Flocculation
“Belle Saison is a Belgian-style ale yeast selected specifically for its ability to create Saison-style beers. Belle Saison lets brewers create Saison-styles easily and with all the expected characteristics noted for this classic style. Designed for warm-temperature fermentation true to traditional production methods, beers brewed with Belle Saison exhibit the “Farmhouse” flavors and aromas making for fruity, spicy and refreshing beer.”
Fermentis Saflager S-23: 72-77% AA, Med/High Flocculation
“Produces a fruit esterness in lagers.”
|Kit Supplied||Bavarian M20||Safbrew T58||Belle Saison||Saflager S23|
|O.G.||1.041*||1.041*||1.041*||1.041*||1.041*||F.G (expected)||1.008 (1.006)||1.008 (1.010-12)||1.006 (1.006)||1.003 (1.006)||1.009 (1.009-11)|
|Attenuation (expected) 80% (85%)||80% (70-75%)||85% (85%)||93% (85%)||78% (72-77%)|
|ABV (expected)||4.3% (4.2%)||4.3% (3.8-4.1%)||4.6% (4.5%)||5.0% (4.5%)||4.2 (4.0-4.2%)|
|Duration||2 days||2 days||2 days||4 days||10 days|
Table 1: * 1 point increase explained by 0.5L drop in volume from original kit
In a blind taste test three people evaluated all five variants head to head. During the fermentation process it was pretty easy to differentiate between them all by smell. After two months in the bottle it was much, much harder to detect differences between most of the aromas. The colours were identical and they were all clear. Only one (S-23) had a head of any sort but we were testing the untreated variant (see next section for carbonation tests).
One of the testers was unable to correctly identify any of the samples by yeast. One other correctly identified three out of five and swapped the M20 Wheat yeast and the S-23 lager. One taster liked the T-58 but disliked the M20 Wheat yeast.
The Belle Saison had the most distinctive taste and aroma of them all.
We'd struggled with carbonating our recent beers (problem turned out to be a small hole in the keg normally used for conditioning) so wanted to try different options to see if we could improve the situation.
So as an additional experiment each batch was split to try different carbonation options:
- No addition
- Small amount of yeast (1/32 tsp in 330ml, 1/16 tsp in 500ml)
- Carbonation drops (one in 330ml, two in 500ml)
- Brewers' Sugar (one teaspoon per bottle)
One 500ml bottle and two 330ml bottles of each.