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Messages - mabrungard

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1
Yeast and Fermentation / Yeast Cell Count, Diameter, and BioMass
« on: July 18, 2018, 05:41:01 PM »
Last night, I attended a seminar in Indy presented by one of the Omega Yeast founders, Lance Shaner. There was one aspect of the presentation that caught my attention. He contends that its not truly applicable to target Cell Count as our metric for yeast starters. He said that the diameters of various yeast variants differ substantially and the amount of mass that those cells contain, also varies. For example, he said that Weizen yeast has much larger diameter and cell mass than something like a Saison yeast.

He went on to state that yeast growth calculators aren't necessarily accurate at predicting starter cell counts due to the differing individual cell mass. However, he did say that their research shows that for a given starter size and gravity, the total biomass produced is relatively consistent...regardless of the cell mass differences between yeast variants. So you might get a far lower cell count when growing a Weizen starter compared to the same size Saison starter, but the sum of yeast mass in each starter is going to be quite similar.

That was surprising to me, but its not when you figure that the yeast are probably utilizing the wort and growing biomass at the same rate, but putting it in different places. One makes fewer, but bigger cells and another makes more numerous, but smaller cells. He did say that pitching rate calculators are flawed do to these factors, they are still reasonably valid for sizing starters.

The final aspect that surprised me was that it is the amount of yeast biomass added to your batch that matters, not cell count. That also translates to a volume of high-viability yeast slurry that should be added to your batch. When he was pinned down, Lance did say that a typical gravity 5-gallon batch would need about 50 mL of high-viability yeast slurry. As I recall, the old clear White Labs yeast tubes probably held about that much slurry. That sounds like an easy to remember guideline for how much yeast slurry we should really be pitching into our batches if you're repitching slurry. Overpitching or pitching directly on a yeast cake may not be best for fermentation.

Give this some thought!

2
General Homebrew Discussion / Re: Brew Systems RO water treatment
« on: July 17, 2018, 12:45:27 PM »
If there's a down-side to the HBrewO system, it seems to me that it's the fact that you need to use their proprietary replacement cartridges. 

Oh, don't worry, there are more down-sides than that. The teeny filters used in that cute, compact system are not sufficient for economical use. However, they do enable the manufacturer to fit all the necessary components in that nice case.

For about a third of the cost of that system, a much more capable RO system that uses larger 10-inch sediment and carbon block filters can be had. Sure, its not as nice and compact, but its actually going to perform better and longer and not put as big a dent in the wallet.

PS: you don't need to buy the replacement filters from the manufacturer since they are a standard part available from many sources. 

3
General Homebrew Discussion / Re: New info on sanitizers
« on: July 17, 2018, 12:31:46 PM »
Im using Distilled water, Bleach and Vinegar for 3 reasons:

1.) It’s dirt cheap;
2.) @ 1 oz./1 oz. per 5 gallons of water it’s no-rinse;
3.) @ that same concentration and the proper pH, Charlie Talley identifies it as a “stone cold killer”.

How much bleach in that mixture and what percentage bleach are you using? I'm cautious.

The vinegar depresses the pH of the solution and that enhances effectiveness.

Another reasonably effective solution is a mixture of distilled vinegar and hydrogen peroxide. Its mixed at a ratio similar to that used to 'pickle' the lead out of brass fittings. Typically a bit more vinegar is added to help drive pH down a bit. That prepared solution needs to react for about a day before use to enhance its effectiveness. This is the dilute form of the Peracetic Acid that many breweries use. 

4
Beer Recipes / Re: German Altbier & Irish Ale Hybrid
« on: July 16, 2018, 08:31:42 PM »
I used S-189 for the first time in a Helles Bock that was outstanding. Great yeast. It does demand proper lagering since that same beer tasted like a hot alcohol bomb for the first 6 weeks. It became a malty and soft example of the style after that.

The manufacturer does indicate that S-189 has more fruity esters than 34/70 when both are used at proper lager fermentation temps. I can believe that. So Dave, S-189 wasn't too ill-mannered when fermented at ale temps? 

5
General Homebrew Discussion / Re: New info on sanitizers
« on: July 16, 2018, 08:26:47 PM »
On Diastaicus, it sounds like they had equal results with that and Brett.  Not absolutely sure.  They also tested lactobacilli with similar outcome.  It looks like iodophor is just slower than ethanol across the board, so not suited to spray bottle use.

Martin, once after a summer hiatus, I found mold growing in my Star San bucket!

Yep! I've seen that too. After a while, things do grow in StarSan solution.

It's clear that we homebrewers have different equipment and timeframes for sanitizing. Pro's have equipment turn-over and production requirements to meet. Time is of the essence for them.

6
General Homebrew Discussion / Re: New info on sanitizers
« on: July 16, 2018, 06:24:33 PM »
I'll +1 on the use of Iodophor. Since switching to Iodophor as my primary sanitizer, I've stopped finding mold colonies in my fermenter. I would often see them when using only StarSan and that is to be expected since it is not effective at killing mold spores. I'm curious if the various sanitizers used in the MBAA study are effective against mold spores?

I realize that breweries are now concerned about Diastaticus in their breweries. I'm curious if its more resistant to sanitizers than other yeast?????

7
Beer Recipes / Re: German Altbier & Irish Ale Hybrid
« on: July 16, 2018, 06:15:11 PM »
I've used 34/70 in a Dusseldorf Alt and fermented it at around 65F and the fermentation character was still very neutral. 34/70 seems to be very tolerant of temperature.

8
General Homebrew Discussion / Re: New info on sanitizers
« on: July 16, 2018, 05:54:58 PM »
I can't review the podcast apparently, but the abstract does provide some indication of their findings.

Hmm, considering that the recommended contact time for no-rinse Iodophor is about 15 minutes, I suppose I'm not surprised that it was ineffective with only 8 minutes contact time. I guess pro-brewers are in a hurry!!

9
Homebrew Competitions / Re: Entering in first competition
« on: July 16, 2018, 12:55:43 PM »
Northern Brewer isn't an American hop. It's English. So you have the hop correct, but that bittering level might be out of style.

10
All Grain Brewing / Re: Plum beer?
« on: July 16, 2018, 12:49:49 PM »
That's like saying grapes are the same as raisins. Not the same.
[/quote]

I'm not ignoring the fact that one form is hydrated and the other is not, but the fact is that their sugars are the same. No significant heating, so the Maillard effects shouldn't be influencing.

11
General Homebrew Discussion / Re: Brew Systems RO water treatment
« on: July 16, 2018, 12:43:36 PM »
Just look at the profile Martin assumes for typical (store bought) RO in Bru'n Water;  it has some significant mineral content left, notably bicarbonate and sodium.

Significant?? A few ppm of any individual ions isn't really much to worry about. That's within the margin of error that we're mineralizing our brewing water to. However, the RO process and resulting water quality is dependent upon the mineralization of the tap water. The raw water that produced the result shown in Bru'n Water has over 600 ppm TDS. 

12
General Homebrew Discussion / Re: NHC Scoresheets
« on: July 15, 2018, 04:28:34 PM »
I'll second the comment that most first round beers need to be rebrewed for the second round. Aged styles can obviously ignore that comment.

The other thing that I do to monitor temperature and packaging effects (to some degree), is to bottle an extra sample of beers that I send off to competition. Those beers are then chilled and sampled at about the same time as the competition to see if my samples are still in good shape. Of course, the variables that I can account for are the vibration during shipment and any temperatures that they experience. My stored samples just get stored at room temperature under my brewing bench.

That extra sample technique does help reveal inadequate packaging techique and the natural aging progression that exists for any beer. Your contest beers are not likely to be any better than your samples.   

13
All Grain Brewing / Re: Plum beer?
« on: July 15, 2018, 01:53:37 PM »
Why aren’t prunes in this discussion?  They’re the same thing.

14
General Homebrew Discussion / Re: NHC Scoresheets
« on: July 14, 2018, 11:31:04 AM »

I agree about the mini BOS "notes"...... I know at that point, the judges are only really concerned with finding the top 3 and it is not about filling out an entire score sheet.  But it would be really great if there was a section for Mini BOS where the judges just wrote down one or two phrases that let you know what the key factor was that knocked your beer out (or set it apart enough to medal). 


You're talking about comparing apples and oranges. There is little more that could be quickly conveyed other than your beer wasn't presenting itself better than the other beer(s). The beers are often different styles and variants.

15
Beer Recipes / Re: Biere de Garde recipe critique
« on: July 13, 2018, 12:06:56 PM »
Looks reasonable. An hour boil should be sufficient since Vienna has reasonably low SMM content. A half hour covered simmer and half hour open boil will do.

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