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tomas77
Joined: 02 Dec 2008
Posts: 1
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 Posted: Wed Dec 10, 2008 9:05 pm Post subject: Plastic aroma |
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| I sometimes get that plastic aroma in my homebrew. It's drinkable but has that aroma a lot. Does anyone know where this might be coming from? Lautering? Yeast? Sparging? Not sure. Thanks for your help. |
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Infidel
Joined: 19 Dec 2008
Posts: 3
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| Posted: Fri Dec 19, 2008 2:42 pm Post subject: |
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I still have the same plastic 5 gallon cooler, plastic false bottom I bought back around 1990, and still use it a few times a year for small batches and I have never noticed a plastic taste or aroma. Are you exposing your (presumably plastic) equipment to temperatures above 170 f or using plastic tube above its heat rating?
If you are using plastic equipment, run hot water through it, cool it, and can taste plastic that might tell you something. |
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Smurfe
Joined: 01 Apr 2009
Posts: 16
Location: Gonzales Louisiana
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| Posted: Wed Apr 01, 2009 6:18 pm Post subject: |
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Probably Phenols. Here is a quick copy/paste that briefly explains:
| Quote: | Phenolic
Phenolics are more prominent as an off-aroma, but also are imparted in the flavor of beer. It is described as medicinal, band-aid-like, smokey, clove-like, and plastic-like. Except in certain styles where small amounts are appropriate, phenols are hugely unacceptable. There are many sources of contamination:
* Chlorophenols exist in municipal water supplies and residue from chlorine-based sanitizers. They can affect beer in parts-per-billion (ppb)! Avoidance of both should be given; find a substitute water supply and avoid chlorine-based sanitizers altogether.
* Phenols extracted from malt during the mash and sparge are polyphenols, also called tannins. They interact with proteins to form chill or permanent haze. If oxidized through hot-side aeration, they create oxidized fusel alcohols. Proper sparging, and avoidance of excessive sparging can reduce the phenolic production. Also, sparge water should be low in alkalinity, and not in excess of 167°F. Likewise, extract brewers should avoid boiling grains.
* Phenols are also derived from certain yeast strains that produce aromatic alcohols. Bavarian wheat beers produce acceptable levels of phenols by creating 4-vinyl guaiacol that results in a pleasing clovelike phenolic tone under the correct conditions. Careful selection of yeast can eliminate undesired affects.
* Wild yeast contamination can harbor within plastic-based equipment, such as polyethylene fermenters and plastic hoses. These materials as soft and permeable, hence difficult to clean. Wild yeasts such as S. diatatius produce minor wort phenols that impart medicinal off-flavors. Migration to glass and stainless replacements are the best solution. Also check for defective bottle caps.
* Smokey phenols are a byproduct of smoked malts, such as in Rauchbier, and Scotch ales. Low amounts are appropriate, but excess use of malt can be overbearing.
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Source: http://www.carolinabrewmasters.com/examstudy/Offflavors.htm
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Smurfe
Joined: 01 Apr 2009
Posts: 16
Location: Gonzales Louisiana
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| Posted: Wed Apr 01, 2009 6:22 pm Post subject: |
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One thing to add. If you are using plastic to ferment in, that is fine but it should be replaced on a regular basis. I have conicals, carboys and buckets. I actually use the buckets more than anything to ferment. I actually do not like fermenting in a carboy as they can be a pain to clean. I do replace the buckets as fermenter every year or two though. Same with your hoses for racking and transfer.
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pincplastic
Joined: 02 Aug 2009
Posts: 1
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| Posted: Sun Aug 02, 2009 8:59 am Post subject: |
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Is it really fine using plastic to ferment in? I just being curious on it?
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Plastic training |
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ibbones
Joined: 03 Mar 2009
Posts: 2
Location: Victoria, Texas
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| Posted: Tue Aug 04, 2009 2:10 pm Post subject: |
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| pincplastic wrote: | Is it really fine using plastic to ferment in? I just being curious on it?
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Plastic training |
Plastic is all I use. I have a bucket and a Better Bottle carboy for a secondary. |
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