Tag: smack pack

The Great American Yeast Starter vs. Smack Pack Experiment – Update on Kegging

I kegged this beer a couple of days ago and thought I should report back on it progress. You may recall the aim of them experiment is to test the assertion that yeast starters are needed for all beers, or whether a single smack pack can be used for “normal” beers with original gravities (OG) of 1.060 without affecting the final beer.

Do yeast starters decrease lag times? I did not notice any difference in lag times between the two fermenters, probably because they started overnight while I was asleep. By the time I checked the fermenters the next morning (maybe 16 hours after pitching), both had a good inch of kraeusen and were churning away merrily. While it’s possible the fermenter with the starter started more quickly, the fermenter that got the smack pack certinly had an acceptably short lag time.

Do yeast starters decrease the time to completion? Both fermenters had very similar times to completion. I checked them morning and evening every day while they were actively fermenting, and they both seemed to ramp up and taper off at about the same time. One interesting thing is that the fermenter with the starter had a thicker, heavier kraeusen which took longer to fall into the beer after the active ferment stopped. The fermenter with only the smack pack may actually have been ready to rack a day or so ahead of the other because of this.

Do yeast starters give more complete ferments? The OG on both fermenters was the same, of course, since they came from the same kettle. Their final gravities (FG) were also the same, at 1.008. This is an apparent attenuation of 86% which is fairly high for the yeast I used (Wyeast American Ale II).

The only remaining questions seem to be related to the flavor of the final beer, which we won’t know for another week and a half or so. The beer is currently resting in its kegs on dry hops and under pressure. Once it’s carbonated and has had a chance to soak up some aroma, I plan on doing a semi-blind test to see if I or my testers can find any difference.

So far, the results seem to indicate that there is little advantage, if any, to making yeast starters when there are healthy smack packs available and when the beer is not above 1.060. The advantages might be more obvious if the yeast in question were older, or if the beer were very strong. As starters cause extra work and therefore increase my overall level of worry (which Charlie tells us is to be avoided in pursuit of homebrew), my inclination is to skip them unless I am doing something extraordinary.

The Great American Yeast Starter vs. Smack Pack Experiment

Yeast starters are widely advocated by homebrewers for all batches. The purported benefits include faster starts, quicker finishes, and more complete fermentations. This is a test to see if these benefits can be counted on for beers of normal strength and if the results are worth the additional work.

Yesterday, as planned, I made ten gallons of beer, which went into two separate fermenters. Both fermenters got exactly the same wort out of the same boiler, and both got the same yeast strain using two smack packs that were manufactured on the same day. OG was 1.056, which is toward the upper end of the range recommended by Wyeast for straight pitching of a smack pack. The date on the smack packs was March 3, several weeks prior to brew day. While I have occasionally found smack packs at my FLHBS that were only manufactured several days prior to purchase, several weeks seems pretty normal. Jamil’s starter calculator tells me that a smack pack of this age should have about 81% viability.

One fermenter got a smack pack that had been smacked at the start of the brew day. By pitching time about six hours later, it was good and puffy. I poured this directly into the fermenter and attached an airlock.

The other smack pack, though, I had smacked the night before and used to make a starter. I used 150g of light DME in 1500mL of water, boiled in a 2000mL flask and then cooled. I pitched the smack pack into this and placed the flask on my home made stir plate, where it spun until brew day was complete – about 20 hours. The entire contents of the flask were added to the fermenter, and an airlock attached.

This morning, about 16 hours after pitching, I checked the fermenters, which have been resting in my ferment fridge at 65 degrees. Both fermenters have a good solid inch of kraeusen, and both airlocks are bubbling actively. It seems like the airlock on the fermenter that got the starter may be bubbling a little more frequently than the other.

So, did one fermenter start more quickly than the other? Without having checked the fermenters hourly all night, I can’t say definitively that one started before the other. However, the lag time on both was short enough that they are well into high kraeusen the next morning. I would feel comfortable with the start time in either case.

I will continue to check the fermenters daily, and will report back on the questions of quicker completion and lower FG.