[harbicide]

I am planning either 15 or 18 gallons of Wit.  Depending on how I grow my starter, using the Wyeast pitch rate calculator:


http://www.wyeastlab.com/hb_pitchrate.cfm
 
I can end up with as low as 8.2 mil/ml or as high as about 15 mil/ml cell count.  Does it matter?

[kramerog]

At the risk of revealing my ignorance, why not use Mr Malty's calculator, http://www.mrmalty.com/calc/calc.html?

[nateo]

There are pros and cons to pitching more or less yeast. Usually, the quality of my beer improves as pitching rate increases, because of decreased off-flavors, decreased lag time, and more vigorous fermentation. I'm skeptical that generating more phenols is worth the down-side (longer lag, less vigorous fermentation, more off flavors, decreased head retention and lacing, etc.) But it's something I've been thinking a lot about lately, and I'm trying to keep an open mind. 

[kylekohlmorgen]

As long as you're controlling temp and not brewing an Imperial Wit, I doubt you'll under-attenuate with a low pitch count, so go for it. Straining the yeast a bit may yield more yeast character. Reducing pitch count is a common practice for getting more character out of other Belgian strains.

Witier yeast can throw some undesired phenols/higher alcohols if you don't keep the temp under control. Start in the mid-60s and let it free-rise 3-4 degrees. Keep it from going over 70F, and I think you'll be fine. 

Please let us know how it turns out!

[nateo]

Reducing pitch count is a common practice for getting more character out of other Belgian strains.

I think that common practice may not be ideal. From my experience, Belgian strains will give plenty of character regardless of fermentation temp or pitching rate. One of the best beers I've ever made was a Belgian Dark Strong that was massively overpitched.

This is entirely anecdotal, so take it for what it's worth. My beer is usually "average," sometimes worse, sometimes better, so I'm not claiming to be an expert on this. I've drank a fair number of homebrewed Belgian beers, and some commercial Belgian beers, that had far too many fusels/off-flavors for my taste. I had an oaked dark strong I entered in a contest in Denver, maybe 2-3 years ago. The OG was 1.095, FG 1.010. I used a whole yeast cake of 3787 from an enkel for it.

It scored really badly for being out of style because of the oak aroma, but the comments from the judges (BJCP certified, an apprentice, and a pro brewer). Here are some of the most frequent comments I got "balanced, smooth, complex, delightful, pleasantly warming, spicy/peppery, currants, very drinkable, 'I love the taste!'" After the contest, I gave a bottle to another certified judge. He was blown away by how balanced and smooth it was, while still having the typical fruity/spicy character you'd expect in a Belgian beer.

I've made a lot of Belgian beers the "low-pitch, hot-ferment" method, and none of them were anywhere near as good as that oaked BDS was. YMMV, but I haven't found underpitching to do anything but make my beer worse.   

[erockrph]

I've made a lot of Belgian beers the "low-pitch, hot-ferment" method, and none of them were anywhere near as good as that oaked BDS was. YMMV, but I haven't found underpitching to do anything but make my beer worse.

I've kinda been wondering if this is an either-or situation. I.e., if you underpitch can you get away with lower fermentation temps, but still retain the phenol character? And if so, do you gain any other benefits (i.e., can you get more phenol with less fusel)?

[Joe Sr.]

I think "ferment hot" is a bit of a misconception.

You can let the temp rise over time, but you still want to pitch at standard temps and you really don't want an uncontrolled fermentation temperature.

[kylekohlmorgen]

I've made a lot of Belgian beers the "low-pitch, hot-ferment" method, and none of them were anywhere near as good as that oaked BDS was. YMMV, but I haven't found underpitching to do anything but make my beer worse.

I've kinda been wondering if this is an either-or situation. I.e., if you underpitch can you get away with lower fermentation temps, but still retain the phenol character? And if so, do you gain any other benefits (i.e., can you get more phenol with less fusel)?

I think you're best off tweaking one variable at a time. Stressing the yeast one way may yield positive results, but its a balancing act. Too much stress will inevitably make bad beer.

I also err on the lower side of ferm temp for most beers (or at least starting low with a controlled ramp-up). When I work on the higher end, I have a difficult time controlling to a setpoint during the peak of heat generation.

Either way, under-pitching and under-oxygenating are methods commonly used by pro's to make excellent beer. It may or may not work in your brewhouse, but its worth investigating.

[nateo]

Kyle - I'm sure pros do it. I'm sure pros make good beer. I'm also sure I'm just not as good at brewing as they are. I'm planning on doing some Weizen trials with over/under-pitching, so I'm not totally biased against underpitching, I just suspect that for my skill level, any small increase in the quantity or quality of phenol production I'd gain by underpitching would be trumped by the possible negatives I listed earlier. Who knows, wouldn't be the first time I've been wrong.

Joe - I think the yeast labs are partly to blame for the misconception. Wyeast lists the ideal temp for 3787 as 64-78*. White Labs lists 530's range as 66-72*, which is a lot more reasonable, but still higher than I'd recommend. Especially in the bigger Belgians, I've gotten better results starting at 60* and raising the temp only after it's mostly fermented.

[Joe Sr.]

I've gotten better results starting at 60* and raising the temp only after it's mostly fermented.

I agree completely.  Also with the fact that the published temps are on the high side.

On the flip side, I'm fermenting a triple with cultured Unibroue yeast.  The Wyeast specs say 65 degrees at the low end.  I had a VERY slow start at 60 and it took off when I warmed it up.  It probably would have gotten there eventually at 60, but I don't like slow starts.

[kylekohlmorgen]

Kyle - I'm sure pros do it. I'm sure pros make good beer. I'm also sure I'm just not as good at brewing as they are.

The only difference is we don't brew EVERY day, so we're shorter on experience. It will take you or I a LOT longer to figure out what works for us. Speaking of which:

I'm planning on doing some Weizen trials with over/under-pitching, so I'm not totally biased against underpitching,

I want to tinker with this as well, so if you get there first - post results! That way I can do one of the 500 other experiments I've thought about but not executed.