Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - nyakavt

Pages: 1 2 [3] 4 5 ... 8
31
All Grain Brewing / Re: Brewing at Twice Strength then Dilluting
« on: May 05, 2010, 03:59:19 PM »
There's a guy at our tailgate that does this with extract, puts 10 gallons of ingredients in a 5 gallon boil.  All his beers have the typical concentrated boil sweetness, tastes like a hint of molasses.  Maillard reactions are increased by increased sugar concentration.  What I suggest for the lighter styles is not to try and do a double batch, but maybe a 1.5X batch (try to stay below some target boil gravity, maybe 1.080?).  Big commercial breweries do this, but I'm not sure what their boil gravity is and where the cutoff lies.  At some point you are going to be able to taste the additional melanoidin development from a concentrated boil, and I can tell you that above 1.100 boil gravity its definitely there.

Efficiency is the other concern, especially if you batch sparge.  Expect at least a 15-20% drop if you go from a 10 lb to 20 lb grist (batch sparging), all else being equal and collecting the same amount of wort.

32
Kegging and Bottling / Re: Check Valves on Gas Distributor
« on: April 12, 2010, 01:56:00 PM »
I find it strange that there are gas manifolds floating around that have shutoffs w/o check valves. What kinda of funky shut off valves does it have, because the "normal" ones sold by most LHBS have integrated check valves.

Sites that are dedicated to commercial products rather than homebrew products will carry distribution manifolds without check valves.  Take micromatic for instance, not only do they not have any check valves at the manifold, but they are also set up for 5/16" line.

33
Kegging and Bottling / Re: Check Valves on Gas Distributor
« on: April 07, 2010, 03:20:09 PM »
I've heard at least one reliable forum member over at NB claim that he got aroma contamination from one beer to another when they were hooked up with no check valves (without any beer backflow), something like a Helles and an IPA on the same gas connection.

As for the manifold, if it's made for a commercial system (sounds like it) then there will be no check valves at each connection because commercial couplers have a built in check valve.  

If you're looking for a DIY, I built a 3-way splitter coming out of each regulator all with check valves for pretty cheap.  The 'manifold' is a 4 port 1/4" FPT air tool splitter from harbor freight, $2 each.  Into each FPT port I screwed in a 1/4" MPT to 1/4" MFL check ball valve ($2.50 each at NB, item K125), then used the standard 1/4" FFL swivel nuts and barbs to connect to the gas lines with a nylon flare washer (item K127, $0.10 each).  Pretty cheap way to go, but there are no shutoffs to each line so you have to do some thorough leak checking.  You could put as many of these air tool splitters in line as you like with a 1/4" MPT to MPT nipple.

34
All Grain Brewing / Re: Bulk grain buy in the Raleigh NC area
« on: March 31, 2010, 12:12:10 PM »
I'm interested, but can't register for the site until I get home from work.  I'll be in for 2-3 sacks.

35
General Homebrew Discussion / Re: FYI: blind taste test
« on: March 30, 2010, 03:42:34 PM »
I was searching for finished beer pH on google and came across this study below.  We don't have a good reference for what the stated levels of aluminum in the beer mean, but it at least indicates that aluminum does leech into packaged beer over time, and does so faster at room temperature vs. refrigerated temperature.

Quote
Detection of aluminum residue in fresh and stored canned beer

This article is not included in your organization's subscription. However, you may be able to access this article under your organization's agreement with Elsevier.

M. M. Velaa, R. B. Tomaa, , W. Reiboldta and A. Pierrib

a California State University, Long Beach, 1250 Bellflower Blvd, Long Beach, CA 90840, USA

b Weck Laboratories, Inc., City of Industry, California, CA 91745, USA

Received 23 May 1997;  accepted 29 September 1997. ; Available online 30 October 1998.

Abstract
The United States produces about 200 million barrels of beer each year from which a large percentage is packaged into aluminum cans. It is important to identify the possible effects a particular foodstuff may induce on its package especially when it is being purchased and consumed nationwide on a regular basis. Very few studies have been done on aluminum can corrosion by beer. The purpose of this study was to compare aluminum levels in fresh, and stored, canned beer representative of U.S. quality draft. A 2 × 2 × 4 design was employed for two brands of beer, A and B, held at two different temperatures of 23 °C (room temperature) and 5 °C (refrigerated) over a period of 5 months. Room temperature beer was found to contain more aluminum (108μgl−1) than refrigerated beer and brand A at room temperature had significantly more aluminum content (546μgl−1) than brand B (414μgl−1) at the end of the duration of storage period. Aluminum content changes from day 0 to day 150 were significant. From these results, it is shown that aluminum cans are corroded over time by canned beer. However this corrosion may be reduced through refrigeration.

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6R-3V091KP-G&_user=798712&_coverDate=10%2F31%2F1998&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1274796816&_rerunOrigin=google&_acct=C000043604&_version=1&_urlVersion=0&_userid=798712&md5=030f70c02f3a94f073e4769ce2aa91f5

36
This beer eventually cleared up, I didn't update this thread because I hadn't recieved a response.  Turns out that the volume I needed to pull to get a clear pint was more than I was used to, about a pint this time vs. 6 oz previously. 

Thus far gelatin has done a great job for me in getting rid of chill haze, and quickly.  Below is a series of photos I took over 4 days after adding gelatin.  The sample was completely opaque after chilling (day 0).  I think it would be quite clear in the glass after day 2 or 3.  Even though there are some particles suspended in the beer, they seem to stay suspended at the same level, so drawing from the bottom would probably not disturb them enough to get a cloudy beer.


37
Yeast and Fermentation / Re: harvested yeast question (brewing today)
« on: March 22, 2010, 01:46:51 AM »

I was under the impression that when repitching
a slurry that is relatively fresh one didn't need
to make a starter? The Mr Malty calculator says I
need 90 mil of slurry. I was just doing the starter
to wake it up a bit. Got to heat some sparge water
and pitch that yeast into the starter.
Thanks


This is correct, a starter is not necessary if the slurry is fresh.  But a starter can be good to wake up the yeast as you said.  It's ok to make a 'wake up' starter smaller than you would for growing yeast, you just want to make sure that you do not let it ferment to completion.  Letting it ferment all the way will do more harm than good as the yeast uses up glycogen reserves to get ready to ferment then has to return to dormancy without growing any new cells.

Just to make sure, you are putting 90 mL of slurry into the starter, not just a couple of teaspoons, right?  You can do it either way, but if you are only taking a fraction of the 90 mL do not expect the small starter to grow enough yeast for the batch, you would need a larger starter or a step up to get enough.

38
Yeast and Fermentation / Re: How long in primary
« on: March 22, 2010, 01:42:11 AM »
Temperature is going to come into play as well, lower temps will help hold off autolysis longer.  The ROT I hear thrown around is 4 weeks is fine at ale temps, longer if you're fermenting at lager temps.

39
General Homebrew Discussion / Re: FYI: blind taste test
« on: March 22, 2010, 01:37:40 AM »
Nyakavt, since I hadn't had any Miller in at least 4 months and didn't taste either one before the test, I could not directly or immediately say which one was from a bottle or a can... what I was able to do was put them in order as to which ones tasted the exact same... ie the two glasses that were from cans were together and the two glasses that were from bottles were together.  Try it and you'll see what I mean.  Thats what kind of surprised me, I liked the extra bitterness of the can.  The bottles are cleaner... softer might be a better word for it?

Oh ok, I didn't realize you did them all together.  This is just as good as a triangle, even a little more difficult since you had to pair down the like beers.  Really want to try this now.

40
General Homebrew Discussion / Re: FYI: blind taste test
« on: March 20, 2010, 11:44:29 PM »
I must admit I'm quite surprised.  Although you didn't repeat this enough times to eliminate chance, it's at least somewhat unlikely that you would guess correctly twice in a row.  Did you find yourself mulling over your choice or was it like instantly 'that's it!'.  What about the freshness dates on the bottles cans, were they comparable?  I'll have to try this myself next time I head to the store.

I'm a bit confused by your taste results, the can was both sweet and bitter?  For me when I taste a beer that is sweet it is lacking in bitterness.  Bitterness could be from metal exposure, but sweetness has to be a fermentation or recipe issue.  You may have had a lot-lot variance which affected the outcome.

If you do the test again, a better one would be a triangle test, where you have two beers from one side and one beer from the other, and you pick out the beer that is different.  When doing a single side-by-side, you know they are different and you can sometimes get a false positive this way.

41
I wonder if anybody performed those tests... if anyone did, some are probably systematically changing out their cookware.   :D  The truth sucks sometimes but its always good to know. 

I don't really see how that relates to canned beer, though.  If the AL pot in your test was lined like the cans are, it would be more relevant.

Exactly, any can for beverage storage is lined so there is no metal in contact with the beverage.  This is just a perception bias that will not stand up to an objective experiment.

Most household aluminum cookware is either anodized or teflon coated anyway.  If you could find an untreated aluminum pot (like a brew pot), how would baking soda added to boiling water be in any way similar to beer?

I have done a blind triangle test with soda from PET bottles vs. a can.  I absolutely could not pick out a difference when they were both poured into a glass.  Before doing this I was certain that I would be able to tell the difference - it was all in my head, associating the flavor of drinking directly from the can.  If we're talking about beer vs. soda, soda is the more corrosive of the two because of the lower pH, and if anything would be more likely to leech metal from the can.

If you are able to do an objective triangle test where the only difference between the beverages is the package (same age, brewhouse, serving temp, etc.), I really don't think you'll be able to pick out a difference better than chance.  You'll have a hard time convincing somebody else of your ability to detect these differences without some sort of controlled experiment.

42
Kegging and Bottling / Re: Keg posts and poppits
« on: March 10, 2010, 04:29:06 PM »
You can get some leak detector at Home Depot, NB also sells some.  This stuff bubbles up even for the smallest of leaks and can tell you exactly where the gas is escaping.  Best to do this without the QD on, just charge up the keg and give a swab.

I can tell you though that if your dip tube o-ring is in good condition, the problem is almost certainly the poppit failing to seal.  It is probably a worn out spring or a deformed rubber seal on the poppit itself, usually the posts are fine unless you can see some gouging or chipping.

43
Kegging and Bottling / Beer still cloudy after 2 servings of gelatin
« on: March 08, 2010, 01:30:36 PM »
Since I started kegging I have been pouring about 1/2 pack of bloomed then heated gelatin on top of the chilled keg.  It has worked great, clear beer in 1-2 days.  But my latest, a Dortmunder Export, is being very stubborn.  I used the dregs of one gelatin package, about 2.5g, and saw no change to clarity.  A couple days later I added another 3.5g and still no change.  This is the first time I've weighed the additions, so I could have been using more than 1/2 pack previously. 

The only major difference to this particular batch was the brewing salts used, lots of calcium chloride and gypsum and some chalk to give high hardness (~200 ppm calcium) and moderately low residual alkalinity.  The mash pH was 5.3 per colorpHast strips, I have not measured beer pH. 

So is there anything I can do to clarify this beer, or is it just chalk that is making my beer cloudy?


44
General Homebrew Discussion / Re: Priming Sugar Data Inconsistency
« on: March 04, 2010, 05:58:47 PM »
Years back, I was frustrated by inconsistency when priming bottles.  I started checking weight vs. volume for corn sugar.  There was a huge difference, depending on how I filled the measuring cup.  Kinda like weighing vs. measuring flour for bread.  I reached the conclusion that volumetric measures for corn sugar were always going to be problematic and went strictly to weighing the sugar.

This is a good point.  I don't know if it's enough to account for a whole ounce, but it's possible.  I think sifted flour is something like 2/3 the density of packed flour.  Plus the resolution in a measuring cup is only 1/4 cup, can be tricky to interpolate.  The only right way to measure this volumetrically is with a dry measuring cup, and then only if there is no 'packing' factor like flour.

We at least know that by weight corn sugar has more moisture and there requires more to achieve the same level of priming.

To steal a quote that Denny posted:

Quote
From Bill Pierce on the HBD....

Date: Thu, 18 Dec 2008 09:23:37 -0500
From: "Bill Pierce" <BillPierce at aol.com>
Subject: Re: Priming sugar

In HBD #5470 Fred Scheer asks about homebrew priming. I have been
priming almost all of my beers, even those that are kegged, for
several years now. I believe that the action of the live yeast on
the priming sugar helps to scavenge oxygen from the head space and
serves to retard oxidation and staling of the beer. I measure the
priming sugar by weight based on the volume of the beer and its
original fermentation temperature, using a rather complex formula
originally presented by Michael L. Hall in "Brew by the Numbers" in
the Summer 1995 issue of Zymurgy (I have incorporated the formula
into my brewing spreadsheet):

Priming sugar weight in grams = 15.195 * Volume of beer in US
gallons * (Desired carbonation level in volumes of CO2 - 3.0378 +
(0.050062 * Fermentation temperature of beer in degrees F) -
(0.00026555 * Fermentation temperature of beer in degrees F2))

The formula is based on the assumption that one molecule of glucose
is fermented by the yeast into two molecules of ethanol and two
molecules of carbon dioxide. It also assumes that the priming sugar
is completely fermentable. It includes the equilibrium volumes of
CO2 already in solution based on the original fermentation
temperature. I stress that measuring priming sugar by weight is
much more accurate than by volume. Thanks to the formula and a
digital scale accurate to the nearest 2 grams, I am able to achieve
precise levels of carbonation in my beers.

I also now use white table sugar (cane or beet) for priming rather
than corn sugar. A couple of years ago I ran out of corn sugar at a
critical time and was forced to improvise. I find no difference in
flavor as far as I can tell. To be strictly accurate, I adjust the
amount of sugar in Hall's formula, which is calculated for corn
sugar.

After some research I found that the extract potential of corn sugar
is 1.042, based on the fact that it is approximately 9 percent
water. The corn sugar used by brewers and bakers is dextrose
monohydrate, that is, with one water molecule bound to each molecule
of glucose. The chemical weight of glucose (C6 H12 O6) is 180 grams
per mole based on the atomic weights, and for water (H2 O) it is 18
grams per mole. Therefore the weight of dextrose monohydrate is 198
(180 + 18) grams per mole, and it is 9.09 percent (18/198) water by
weight.

I confirmed this with an experiment in which I weighed 119.9 grams
of corn sugar with my laboratory balance and added distilled water
at 20 degrees C until the volume was 1 liter (measured to the
nearest 2 ml, the accuracy of the graduated cylinder I was using).
The weight and volume I used are merely scaled from the 1 pound and
1 US gallon used in calculating the extract potential. The measured
specific gravity using my reasonably accurate hydrometer was 1.042.

The extract potential of sucrose is 1.04621, used as a reference
value for gravity and alcohol calculations in brewing. Therefore I
prime with 90.9 percent (42 gravity points divided by 46.21 points),
or 91 percent in round numbers, as much white table sugar by weight
as the corn sugar calculated by the formula.

Brew on!

Bill Pierce
Cellar Door Homebrewery
Burlington, Ontario

45
General Homebrew Discussion / Re: Priming Sugar Data Inconsistency
« on: March 04, 2010, 05:45:54 PM »
1. 4.66 oz white sugar will provide the same level of carbonation as 4 oz corn sugar, making corn sugar more "carbonation potential dense" for lack of a better term.

I thought 3/4 cup of corn sugar is roughly 5 oz, not 4?  I think this is the source of your discrepancy.

Pages: 1 2 [3] 4 5 ... 8