fermenting questions

[wibbley]

Hi all,

I have read loads of books, including the on-line one and they all have differing approaches to fermentation.
Normally I let the wart cool, pitch in the yeast & let it cook for a week in an open top bin. Then transfer to an airlocked fermenter for a few weeks, then into the barrel.

This time I thought I would have a go at 'dropping' so after 2 days I siphoned into a new sterilised open top bin. I was expecting a new head to form on the top, but only got bubbles so threw in some more yeast. After a few more days got a thin layer of brown stuff on top. Is that right? I was expecting a new head to form similar to the original. My book says "a new head will soon form"

How do you guys do it?

BR,
Wibbs.

[hoppingMad]

Hi wibbley, I'm going to assume plenty here, as there's not much information to tell me where you're at exactly.

Normally ales use ale yeast which is knowns as Top Fermenting Yeast. Generally (but not always) you will see a foam head on top of the fermenting wort. Sometimes its quite a dense mass, other times its not. It can be said the this head protects the beer, to some degree, from contamination. However you would be well advised to keep your wort in a sealed, sanitised fermenter with a sanitised airlock fitted right from the start when you fill it on brew day. Allow it to cool if necessary, then open and pitch your yeast as soon as possible when at your preferred temperature ( normally right away) . You might get away with your present uncovered fermentations for a while but sooner or later an infection is sure to result.

Dropping is not something I do, nor do I know anything about it so won't comment too much on this, except to say that you ought to have a good reason to do it, and if you don't, then maybe its best not to do it.

What aeration procedure do you use ? i.e. do you syphon the wort into the fermenter and let the stream cause aeration? or do you shake ? or perhaps use a vigorous stirring ? All are good, but you should be doing one of these.

With adequate aeration, you should get a fermentation all the way to the finish without the need to transfer. ( not talking about a secondary fermentation or cold conditioning) If your beer is "stalling" part way, it could be in part, due to insufficient aeration. You should not need more yeast. ( there are other factors too ) Yeast need oxygen to multiply. However, sometimes we use the slurry straight away from another completed fermentation, and in this case there could be a huge number of viable yeast cells still working, and aeration, whilst still a good idea, may not be quite so important. If you are pitching a new packet of dried yeast, then don't worry about this slurry concept. Dried yeast sachets contain plenty of yeast.

Someone else can comment on your "dropping" issue.
Cheers,
Hopp.

[wibbley]

Thanks for the swift reply.

I aerate by having the boiled wort above the fermenting bin (a plank across the bath) and open the tap on the bottom of the boiler. I have a strainer inside the boiler which according to the destructions (sic) uses the hops as a filter bed.

I get great fermentation no problem, however when drropping (after a couple of days) the thick yeast head does not re-appear. Now it maybe that this is correct as the yeast has now settled down. There are plenty of bubbles coming up, just not the big thick creamy head as in the first couple of days.

On a side note, I find the bath great for brewing beer. Not literally u understand. I have an adapter on the tap's shower connection for a hose used rinsing things down/fillings thing up. With a plank across the bath giving a step so ones bin/boiler can be mounted above another. It saves having to lift or move 5 galls of boiling liquid. I have two boilers so for sparging I have the mash tun and one boiler on the plank, the tun then empties into the boiler below which I energise as soon as the element is covered, saving much time getting to boiling point. My local home brew shop (within a health food shop) and everything was sold off at half price. I bought most of it and have plenty of equipment

[Jim]

Agree with the previous comments about using open-top fermenters (though an airlock isn't strictly necessary if you have a tight-fitting lid). The breweries get away with it because they have huge volumes of wort fermenting which creates a thick head. They also take precautions against flies etc getting into the fermentation area.

Sticking fermentation is a known side-effect of dropping, by the way.

[Aleman]

A lot of the micros I know who use open fermenters still cover the FV with a plastic lid until the yeast head has formed.

Dropping is a technique that either works for you or doesn't, some people do it and have no problems, others hit major issues. If I am ever going to drop a beer I always do it early . . . before major fermentation starts (if the little white islands of bubbles/foam are starting to form that is the latest I would consider it), and I would allow the wort to splash into the second FV, the added aeration allows further yeast reproduction, and complete fermentation in big beers. It also allows you to get the wort off any trub carried through from the boiler.

Most of the 'benefits' of dropping can be replaced by pitching enough yeast in the first place . . . the little 6g kit sachets are not enough. . . . 11g is a minimum in 5 gallons

[Northern Brewer]

If you are using SO4 then you need to drop 24-36 hours after pitching otherwise it may struggle to produce suffcient CO2 to refill the head space. Interestingly, Graham Wheeler, who persuaded many home brewers to experiment with dropping, apparently no longer advocates it, due to the risk of stuck fermentations.

I always use sealed fermenters because I struggle to envisage the yeast head as being 'protective'. I accept that the head acts as a barrier between the beer and the environment, but this barrier then sinks into the beer, taking with it whatever bugs it was protecting the beer from. I'm assuming this doesn't usually create a problem because by this stage the beer contains alcohol, which has certain antiseptic properties.