This experiment was designed to evaluate different Weissbier yeasts. The following yeasts were used:

• 351-1 (This yeast came from a WLP351 vial, but I think it is not the WLP351 strain anymore)
• WY3068 – Supposedly the W68 strain from yeast bank Weihenstephan. A very popular strain among German brewers
• WY3333
• WY3056 – Initially a blend of yeast, but I cultured this one from a single cell colony

The wort was a simple Helles Weissbier wort:

• 70% Weyermann light wheat, 30% Weyermann Bohemian Pils
• Step mash (55 C for 30 min -> infusion of boiling water -> 65 C for 45 min -> thin decoction boiled for 10 min -> 72C mash-out)
• 3.7g 10% Target and 7.5g 8% Northern Brewer hops boiled for 60 min
• Boiled for 60 min in a 2 stage boil: 1st stage just a simmer, 2nd stage with a 12 %/hr boil-off. I wanted to see if that type of boil, which is done by many commercial brewers, actually works for avoiding DMS. No noticable DMS was later found in the beer
• Cast-out wort: 16l @ 11.5 Plato

 4 one galon glass jugs were filled with 3l wort each. They were oxygenated with pure O2, but I did not take ones on how long (30s are likely). The following amounts of yeast were pitched

• 351-1: 10 ml sediment, propagated from an agar culture
• WY3068: 50 ml loose sediment from a Wyeast activator pack
• WY3333: 35 ml thin slurry from a Wyeast activator pack
• WY3056: 10 ml sediment propagated from an agar culture

It was noted that the pitching rates were rather different, but time and availability didn't allow for all yeasts to be grown the same way to the same amounts.

The yeast was pitched at 18C and since all growlers sat in the same water bath, it was assumed that they would have the same temperature. The temperature measured is the temperature of that water bath and because of the good heat conductivity the actual fermentation temperature was not expected to be different.

Over the next 2 days the temperature rose to 21C (70F) before it fell down to 20 C. The 2nd day after pitching the following extract values were measured:

• 351-1: 7 Plato
• WY3068: 6.5 Plato
• WY3333: 6.5 Plato
• WY3056: 6.0 Plato

Alongside the primary Fermentation, a number of fast ferment tests were done:

• dry bread yeast (1/4 tsp to 150 ml) : 2.5 Plato
• dry bread yeast (1/2 tst to 150 ml) : 2.5 Plato
• WY3056 : 2.5 Plato
• WY3333 : 2.6 Plato

The beers were bottles with residual extract. This means that the beer was simply filled into bottles once the extract level reached 3.7 – 3.8 Plato, which leaves enough residual fermentable extract to properly carbonate the beers. A practice called Gruenschlauchen in German Brewing.

During bottling a strong banana aroma was noticed for WY3056 and WY3333.

After one month (I didn't get to it earlier) the 4 beers were tasted together:

WY3086:

The beer pours a very strong head and is well carbonated. It's aroma shows moderately yeasty notes with some sulfur. The taste shows a little of the Weissbier clove spiciness but hardly any banana even though the beer smelled like banana juice at bottling time. The final extract was 2.7 Plato.

WY3333:

The beer is highly carbonated. It's aroma is yeasty with some banana/bubble gum character. But that fruit was very strong and came out later when the head subsided. The taste shows a restraint spiciness but no fruit. It is also a little yeasty, but more in a good way. Final extract 2.7 Plato. 

351-1:

The beer was not as well carbonated as the others and didn't pour a strong head. This is odd since this yeast is actually able to ferment below the 2.6 Plato of the other beers and was bottled with at the same extract level as the other beers. As a result more fermentable sugars must have been fermented that should have resulted in more CO2. The aroma spots some solvent notes (ethyl acetate). Later, the aroma is more clove dominated. It's taste is more spicy than all the other ones with less yeasty character. Final extract 1.6 Plato (!!)

WY3056:

The beer is highly carbonated. The aroma is clean initially, but once the head fell it showed a slight yeasty character. The taste is bready-yeasty (in a good way) without any signigficant spiciness. This character might make this yeast ideal for a Dunkles Weissbier. Final extract 2.8 Plato.