I am brewing a porter with an OG of 1.060, 6 gallon batch.
I picked up some older WLP002 the other day…packaged on Feb. 18, and the “best by” date is sometime next week. I have no issues making starters, so I figured this wouldn’t be an issue. I bought 2 packages.
The Mr. Malty calculator tells me that I have to pitch at least 5 packages into a 2.96 liter starter in order to get to my desired pitch rate of 250 billion cells. Beersmith has me getting to the same place pitching my 2 packages into a 1.43 liter starter (both using a stir plate).
I’m confused. Any recommendations? If I have to pitch 5 packages to get a viable starter, I think I may just cut my losses and go buy a fresh package.
IMO, it just doesn’t matter all that much. I’ve been through the whole evolution on starters…from nothing, to a simple 2 qt. starter, to stir plates and calculators aand crashing and decanting and now back to a 1 qt. “shaken, not stirred” starter 24 hours before brewing. And ya know what? My current procedure is not only easier, but I feel like it produces beer superior to using any of those other methods.
I follow the same shaken not stirred approach. I find it much simpler, and saves the bother of having to remember to get a starter going 2-3 days before I want to brew.
In Mrmalty.com there is a slider that you can set to fewer packs/vials and it tells you the bigger sized starter to make for your one vial.
These calculators are all math models of the yeast propagation. To really know how much you are pitching, you need a microscope and a hemocytometer so you can count cells. Some have those bits and know how much they are pitching. A forum member who is not active these days convinced many of us to pitch at high Krauesen, as the yeast are viable and in the state where they will reproduce in the wort when pitched, rather than having to wake up from being crashed.
I use pure O2 for the “Lazy, Not Stirred” method and I’ve found several advantages over my previous stir-plate method:
I don’t have to decant any starter wort (I just pitch it all in at high krausen and adjust recipe/volume if needed to factor in that I’m adding a liter or two of pale beer at ~1.040)
I can do this the night before or day of brewing
Significantly shorter lag time
Better tasting starter (I like to taste everything in the process; having the starter taste better makes me more confident that I’m improving things)
As to your original question – the dates and rates are all estimates based on way too many variables that you can’t know (i.e. how the yeast was treated before you received it, including all of the shipping time, etc).
If you take the “no worries” approach you’ll have a few more hours of lag time while the lower mass of yeast reproduces to take on the 1.060 wort. As long as your sanitation is good, you’ll still make fine beer and in a porter likely won’t notice esters at a sufficient quantity to be an issue.
If you take the “not taking any chances” approach, you can add a fresh pack, decrease your lag time, and end up in arguably the same place (with fewer esters, etc, but likely not enough to notice in this case).