Will Not Hold Head

[bob58]

Hi fellow brewers
The last couple of extract brews I have done taste great but don't want to hold there head after the first pour have been using us05yeast any ideas why
Cheers Bob

 

[roverfj1200]

Make sure your glasses are clean and rinsed. Use a fresh glass each pour. Rinse all equipment of detergents..

Cheers.

 

[Nick JD]

Carapils steepable grain. Try 300g in 3L of hot tap water for 30 minutes - add 200g of LDME and boil your hops in it.

 

[GOLIATH]

Hey Bob, What was yr brew temp?? The other issue you DONT have control of, is the mash temp used to produce the kit extract. So dont automatically assume that its something you have done. Further, are you absolutely certain there is no infection? Bearing in mind that many HB ers, dont easily recognise them!

The reason I ask is that Bacteria will chew out sugars differently to yeast and invariably will produce head killing compounds even if there was an ok ferment at the end, there may have been sufficient action for this to occur.

I am assuming that the glasses and stuff are ok, we are all pretty fussy about that. Additional crystal malts like carapils are a good idea for body but you should really eliminate the fundamental issue before spending more money.

Regards Dave

 

[Aus_Rider_22]

Make sure your glasses are clean and rinsed. Use a fresh glass each pour. Rinse all equipment of detergents..

Cheers.

Honest question: Why use a fresh glass each pour? I would thought if you are washing them right then they are fine to keep using. The beer would flush out any residual contaminants, excluding stuff from the drinkers lips.

bob58: What are the recipes you brewed? Here's a good article regarding the washing of glasses. http://www.aussiehomebrewer.com/forum//ind...;showarticle=70

in particular this method,
There are many ways to clean glasses....the best way I've tried, is Batz's method....
put some bicarb in the glass
add just enough water to make a loose paste
rub vigourously inside and out
tip out any excess
pour in a bit of white vinegar, shake it around and watch the foamy fun.
rinse with water
drip dry.

 

[dr K]

Bacteria will chew out sugars differently to yeast and invariably will produce head killing compounds even if there was an ok ferment at the end, there may have been sufficient action for this to occur.

How?
What head killing compounds will they invariably produce?
Just interested as it is a novel concept to me.


K

 

[GOLIATH]

Specifics huh! and a good question, now I have to find the reference and answer it I will.

My general understanding from long ago is that the compounds and esters produced by bacteria in a wort are very different to those produced by yeast, hence the weird smells and tastes often making it undrinkable. Often however, yeast will overcome due to the difference in cell size but .......too late.

I'll have to dig out some old books and will try to get back to you tonight with something more specific.

Regards
Dave

 

[dr K]

I look foward to it, anything to increase our knowledge of brewing (backed by references of course) is always positive.

K

 

[GOLIATH]

OK, Heres a start. Remember its been nearly 6 years so im a bit rusty.

Brewchem 101 ISBN 0-88266-940-0 Janson.

This is not the answer I was looking for but its a start and I quote.

" LIPIDS for the purposes of this discussion are fat like molecules that come fro 3 sources: Malt, Oxidised Hops and yeast metabolism. Trup that collects at the bottom of your fermenter can contain as much as 50% lipids. Cloudy wort contains from 5 to forty times the lipid content of clear wort. So what do Lipids do anyway?"

"Lipids transport nutrients across the cell wall and cell membrane and inhibit the formation of SOME unpleasant esters. One of the drawbacks is that they decrease head retention by acting like soap and literally dissolving the foamy head and also play an important role in beer staling. They are easily oxidised and will contribute "Soapy" Fatty" "Sweaty" or "Goaty taste to beer"

" Because lipids have such strong benefits and drawbacks some feel a positive contribution from lipids is best achieved by transferring wort to a secondary fermenter after a few dayswhen initial fermentation is complete. This allows yeast access to lipids during the critical starting stages of fermentation then removes the wort from the high lipid trub on the bottom of the fermenter"

Doc this method is also referenced in "The new complete joy of homebrewing".

More to come re-bacteria in a minute. its a good read so far

Dave

 

[manticle]

I realise you have more to search for and it should hopefully be interesting but lipids and bacteria are completely separate.

 

[GOLIATH]

yep... might be mind rust. but its there somewhere

Dave

 

[manticle]

It makes sense intuitively - if residual sugars contribute to head formation and retention then anything that can ferment those residuals (like brett or bacteria possibly) might therefore affect such things. Interested to see some actual data though.

 

[GOLIATH]

Nope, cant find it yet, but will because now i'm really keen to find it. Im having a good read again though.

There is this one though although its close, ....but no cigar.

Starts with an understanding that High Alcohol beers or beers with solvent like flavours have difficulty holding head.

"The sweet flavour of ethanol, a two carbon form of alcohol, is desired in beer. Longer chain alcohols, including propanol (3 carbons) Butanol (4 carbons) and related molecules are desired in limited quantities in high-alcohol beers like strong ales and barley wines or in certain beer styles such as bock or double bock. However, excessive amounts of these larger alcohols, the so-called fusel alcohols(propanol, butanoi, isobutanol, isoamyl alcohol) and phenolic alcohols (tyrosol) create a number of disagreeable off flavours especially in lighter beer styles. Ethyl acetate formed by the combination of ethanol and acetic acid is often a major contibutor to a solventlike off flavour"

I read this as it will also be a significant contributor to a stuffed head retention as it is a solvent.

"These undesirable tastes can be due to a number of causes including high fermentation temps, excessive yeast growth, excessive levels of amino acids and their resulting metabolism and/or high evels of ethanol that will not allow normal fermentation. In summary, fermentation thats too fast or too strong or uses the wrong yeast starter ingredients can overload the normal ethanol producing pathway resulting in undesired products. Too much ethanol will also result in these alternative fermentation pathways if the yeast are weak ." Heres the comment " Bacterial infections will also lead to alcoholic and solvent like molecules being produced especially ethyl acetate"

I hope thats a bit of interest to some! I'm still looking for a direct reference but I have lent a lot of books over the years and havent got them all back. Its not a copout but is for now.

What I can understand from the text and experience is that bacteria DO utilise sugars in a wort for their own growth and that the differing cell sizes allow yeast to get the upper hand. Further, that there are by-products from all biochemical reactions whether yeast or bacterial.

Ill keep looking, maybe its worth a question on a few forums if I havent got back to you soon.

Regards
Dave

 

[dr K]

No doubt about large amounts of lipids screwing up your head, but the first reference describes three sources of lipids none of which are of bacterial origin. The same reference notes that " trup" , I assume trub, but it could easily be "tup" contains up to 50% lipids, which would lead me to think that our beer is pretty full of lipids anyway.
No doubt that fatty acids can lead to goat like flavours, but the yeast has to be pretty stressed, and if its that stressed ther will be so many other adverse flavours you well may not pick them.
Still, as Manticle points out , no invariable connection between bacteria and lack of head.

K

 

[Adamt]

The most common bacterial infections produce acetic or lactic acids, along with extra carbonation, neither of these would detract from head retention, in fact the carbonation would help it. The fermentation of higher sugars by the bacteria that are not fermented by the pitched yeast could detract from it though.

But, in this case, considering they "taste great", and no mention of gushing, I'd doubt there'd be a bacterial infection (at least, not advanced).

I'll back the call for the OPs recipes.

 

[GOLIATH]

I am not trying to confuse lipids with bacterial infection, am aware of the difference and did not mean to infer otherwise. I am not a chemist and have been out of brewing for quite some years. I can only apologise for not having answered your question yet.

Whilst reading texts I thought the oxidised lipid discussion might be something helpful for the thread because its about head retention after all. Don't mean to confuse.

I need to shed some light on it because this (The compounds resulting from bacterial infection as an impediment to head retention) is an understanding learned long ago and I cant find a good reference. Yes I did mean "Trub" sorry.

Regards

Dave

 

[Adamt]

It's good to see you back on the boards Dave, and always good to see some brewing discussion.

 

[GOLIATH]

Thanks Adam,

I'm being challenged here and am prepared to admit that I may be wrong. I am still looking though. I always had the understanding that bacterial infections produced other compounds that affected head retention and I used the word "Invariably" aaaand now i'm paying for it. Dr K has an agenda here regarding my post and he may know for sure, but hes not saying so onward we press. You should see my lounge, Ive even got The institute of brewing journals out! Anyway, I can always say sorry if im completely wrong and have wasted everyones time!

Thanks for the post, God to see you are still at it!

Regards
Dave

 

[Fourstar]

Aaaaaaand back to the OP question.

As noted earlier, can you give us a breakdown of the recipe's you have had issues with indead of "they are extract beers".

As for the 'soapy glasses'. Forget that as i doubt its your real problem if you wash by hand and definitly not an issue if you use a dishwasher as the cleaners are primarily oxygen based (like nappisan).

I always point people to this article as its a great starting point: http://www.byo.com/stories/article/indices...5-fabulous-foam

The two things i'd look at first are adding some crystal malt or carapils which is a dextrin malt used to increase body and foam formation to your beer by steeping it and doing a short boil to kill any nasties. (you want the proteins from the malt)

Next i'd look at doing a short hop boil as its likly you are getting your hops in ISO form if you are using kits. Hop oils and resins aid in the formation and stability of foam (like dishwashing liquid).

Cheers! :icon_cheers:

 

[MHB]

Adamt
The most common bacterial infections produce acetic or lactic acids, along with extra carbonation, neither of these would detract from head retention, in fact the carbonation would help it. The fermentation of higher sugars by the bacteria that are not fermented by the pitched yeast could detract from it though.

But, in this case, considering they "taste great", and no mention of gushing, I'd doubt there'd be a bacterial infection (at least, not advanced).

I'll back the call for the OPs recipes.

Well thats half right (maybe), Lacto does produce CO2 as a by-product of fermenting sugar, tho it will I think only tackle very simple sugars.
Acetic acid production doesnt add any carbonation at all. Acetobacter dont attack sugars they dehydrogenate alcohol.
I think there is very good evidence that far from being the most common infections Aceto and Lacto are just among the more noticeable infections most home brews (and a lot of commercial offerings) are infected to some extent.

When it comes to head we have to look at both formation and retention, the improvement in head retention gained by adding some wheat to a brew cant be understated, in fact I now add 100g of Dry Wheat Malt Extract to all the blends I sell in my shop.

As for some of the other ideas presenter I, like Dr K am waiting more some more evidence, there are a couple of ideas here that dont quite ring true.
MHB