Hot wort->cold water..bad?

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Question:

As I am new to this: what is Hot Side Aeration? Can someone please explain? — Feddo Wouters Nijmegen The Netherlands

Response:

As I am new to this: what is Hot Side Aeration? Can someone please explain?

HSA is the exposure of hot wort to air. Under such contitions, some compounds in the wort will undergo oxidation that after fermentation produce a wet cardboard like flavor. — Phil

Response:

– Hide quoted text — Show quoted text – I go one step further and wonder if anyone can tell me whether it shouldn’t be done, and if not, why. I don’t have a wort cooler; I do extract brews with a 50% boil, and then dilute before pitching with cold water. All the evidence I have heard suggests that cool-down time is the period when you are most likely to get infections in your beer. Accordingly, lately I have taken to pouring the hot wort over 8lb. of good-quality commercial ice, and then diluting with cold water: it’s ready for pitching almost immediately. Pouring hot wort can lead to hot side aeration (HSA) which produces cardboard like flavors. Ice can contain microbes. What constitutes good quality commercial ice and how confident are you that it is microbe free? A wort chiller will only cost you about $25 to make. It is an investment well worth making. — Phil Has anybody in this group ever experienced the cardboard tast and then be able to trace it to HSA in their brew process?

Good question. I guess maybe someone has, but I have not. I’ve been brewing for about fifteen years and when I began I used the crudest of methods such that even beginners would cringe. I dumped the hot wort into a fermenter partly filled with cold water for many years before I ever even heard of HSA. Only once have I tasted the dreaded wet-cardboard flavor, and I attributed that to using some old LME that was discounted by the supplier to unload it (last time I went for a "bargain" in brew supplies). My technique has come a long way since then (bought my first chiller around ‘88) and I hear and read lots about how bad HSA can be but I have never experienced any problems with it myself, even back when I routinely tempted fate. [snip] (When I was an extract brewer, I’d always add my hot wort to cold water, and never noticed the "cardboard" taste..) comments?? nimbus

Me too. I think the potential for HSA to cause noticeable off-flavors is over-emphasized (unnecessarily) in this respect. tracy

Response:

Do they purge the air out of the whirlpool vessel with nitrogen before introducing hot wort? — Phil

Response:

- Hide quoted text — Show quoted text – Has anybody in this group ever experienced the cardboard tast and then be able to trace it to HSA in their brew process? I know that some commercial breweries use a whirlpool following their boil, and in the process of the transfer to the whirlpool the hot wort enters the whirlpool vessel above the liquid level tangential to the vessel, essentially spraying down the inside wall. This gets the liquid whirling, but it seems like HSA would result. Yet the product tastes fine. Do they purge the air out of the whirlpool vessel with nitrogen before introducing hot wort? — Phil

No purging is done; so there must be HSA, or at least the potential for it. I was surprised to see this done without any concern after the discussions of HSA I’ve seen on this group and in some brewing magazines. A friend of mine has the Declerk (sp?) book, which I think is where I saw a similar whirlpool design illustrated and discussed, so maybe I’ll take a look at it. The brewer I asked about it said, yeah, I guess it might have some effect. That’s what gives our beer its distinctive flavor. (however he was somewhat joking when he made that comment. Any flavor I notice certainly isn’t objectionable).. nimbus

Response:

- Hide quoted text — Show quoted text – I go one step further and wonder if anyone can tell me whether it shouldn’t be done, and if not, why. I don’t have a wort cooler; I do extract brews with a 50% boil, and then dilute before pitching with cold water. All the evidence I have heard suggests that cool-down time is the period when you are most likely to get infections in your beer. Accordingly, lately I have taken to pouring the hot wort over 8lb. of good-quality commercial ice, and then diluting with cold water: it’s ready for pitching almost immediately. Pouring hot wort can lead to hot side aeration (HSA) which produces cardboard like flavors. Ice can contain microbes. What constitutes good quality commercial ice and how confident are you that it is microbe free? A wort chiller will only cost you about $25 to make. It is an investment well worth making. — Phil

Has anybody in this group ever experienced the cardboard tast and then be able to trace it to HSA in their brew process? I know that some commercial breweries use a whirlpool following their boil, and in the process of the transfer to the whirlpool the hot wort enters the whirlpool vessel above the liquid level tangential to the vessel, essentially spraying down the inside wall. This gets the liquid whirling, but it seems like HSA would result. Yet the product tastes fine. I’ve even seen whirlpool designs in one of the classic brewing texts that look like this. (When I was an extract brewer, I’d always add my hot wort to cold water, and never noticed the "cardboard" taste..) comments?? nimbus

Response:

I go one step further and wonder if anyone can tell me whether it shouldn’t be done, and if not, why. I don’t have a wort cooler; I do extract brews with a 50% boil, and then dilute before pitching with cold water. All the evidence I have heard suggests that cool-down time is the period when you are most likely to get infections in your beer. Accordingly, lately I have taken to pouring the hot wort over 8lb. of good-quality commercial ice, and then diluting with cold water: it’s ready for pitching almost immediately.

Pouring hot wort can lead to hot side aeration (HSA) which produces cardboard like flavors. Ice can contain microbes. What constitutes good quality commercial ice and how confident are you that it is microbe free? A wort chiller will only cost you about $25 to make. It is an investment well worth making. — Phil

Response:

Hi all, Had a discussion with a friend the other day about why his beers never turned out good. I suggested a few things but had a mental block on the controversy about dumping your hot wort directly into the cold water in the primary and the problems it can cause (ie. off flavours etc.). Any one care to comment? Thanks. Stu — _ / ._ _|_ _.._ o _ Stu Miller – Moderator of LIMS mailing list

Response:

controversy about dumping your hot wort directly into the cold water in the primary and the problems it can cause (ie. off flavours etc.). Any one care to comment?

Silly question. In the winter we bury the primary with the sterile water in the snow, then we dump the hot wort into the secondary with water near freezing. I have not noticed any off tastes, but thats just me! paulc

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