Extracting Tannins

[KoNG]

what was your OG ash....?

 

[Ash in Perth]

i must have opened that and took my sweet time to post because i missed most of those posts earlier today.

Ok heres the recipe:

12L Batch:

3kg Marris Otter
250g Weyermann Munich
150g TF Caramalt
150h TF Crystal

mash 2.8L/kg at 66DegC , single infusion, efficiency only 70, OG 1.062

FWH 10g Target (24IBU)
30min 20g Target (26IBU)
10min 35g Styrian Goldings (8IBU)
5min 20g EKG (4IBU)
0min 15g EKG

All hops were normal pellets

Fermented at 20DegC using wyeast 1275. FG 1.013.
5 days primary, 6 days secondary.

 

[Kai]

I'd be blaming the hops. You've got enough in there to stun a mullet.

 

[Darren]

I'd be blaming the hops. You've got enough in there to stun a mullet.

[post="126539"][/post]​

Ditto/snap

 

[Ash in Perth]

i like hops. I was suprised that the falvour and aroma intensity was not as big as expected. and the bitterness did not seem at all like 65 IBU.

 

[Trough Lolly]

Ok heres the recipe:

12L Batch:
3kg Marris Otter
250g Weyermann Munich
150g TF Caramalt
150h TF Crystal
mash 2.8L/kg at 66DegC , single infusion, efficiency only 70, OG 1.062

FWH 10g Target (24IBU)
30min 20g Target (26IBU)
10min 35g Styrian Goldings (8IBU)
5min 20g EKG (4IBU)
0min 15g EKG

All hops were normal pellets
Fermented at 20DegC using wyeast 1275. FG 1.013.
5 days primary, 6 days secondary.
<and>
... i like hops. I was suprised that the falvour and aroma intensity was not as big as expected. and the bitterness did not seem at all like 65 IBU.

Thanks for the additional info, Ash...Next time you do this brew, chuck your hydrometer in the kettle, after you finish the sparge and before you flame on for the boil - I'd bet that you have a fairly strong gravity given that you have a touch over 3.5kgs of grain in the mash.
//beergeek mode commences!//
I too agree that it's the hops as your primary culprit - the extraction efficiency of the hops is impaired somewhat as the preboil wort gravity increases. This, of course, is also dependant on your extraction efficiency but I'd say that you have a concentrated wort of small volume and you've possibly used a computer recipe generator to add hops to achieve a desired IBU level, but the computations cannot compensate for the chemical effects of high gravity concentrated wort boils.
To put it simply, the computer or your calculator gave you a mathematically correct response, based on predetermined formulas but there's nothing there to calculate the complex reactions that will occur with 100g of hops in 12 litres of boiling wort.

Do you freeze your hops? How old are they? Most of the soft resins in hops consist of Alpha Acids and Beta Acids. The major bittering contribution from hops is derived from Alpha Acids and over time, the Beta Acids contribute bittering as a result of the Beta Acids becoming oxidised during storage and in the subsequent boil.
Over time the Alpha Acids deteriorate and so the Beta Acids tend to balance out the bittering potential as the Alpha Acids decline - and therefore it's an important and often overlooked value - the hop Alpha:Beta ratio. Fuggles and EKG for example have an Alpha:Beta ratio of 1:1 which looks good on face value, but conventional wisdom suggests that a 2:1 ratio actually results in a more constant bittering potential. Fuggles is often maligned as a poor bittering hop - but the true is more likely due to poor storage or using stale Fuggles that has a much higher Beta Acid content than it's Alpha Acid content when it was originally harvested.
The 2:1 rate suggests that the Alpha Acids deteriorate at a greater rate than the increased bittering potential of the Beta Acids. The bittering effect is also different between Alpha and Beta - some suggest that the Beta acid bittering is substantially harsher compared to Alpha acid bittering....anyway I better drift back on topic before you completely fall asleep!!

According to your recipe, you've added some 70 grams of hops in the last 10 minutes of the boil. It might be worth repeating this brew, but substantially reducing the amount of hops you add late in the boil or conversely, substantially increasing the boil volume. With large late additions you only add a relatively small amount of Alpha Acids, since they need heat to complete their isomerisation into the wort (in general, a 45 minute boil only yields a 30% isomerisation of the Alpha Acid bittering potential in the hops), but you have also contributed a substantial quantity of aromatic hop oils and essences, as well as substantial quantities of hop polyphenols into the solution which are known to add a tannin like dryness to the wort.

Cheers,
TL

 

[warrenlw63]

I'd be blaming the hops. You've got enough in there to stun a mullet.

[post="126539"][/post]​

Or if you reside in SA to perhaps grow one. :lol:

Warren -

 

[T.D.]

Yeah that's a lot of hops for a 12L brew. I Brewed a hoppy IPA with Challenger hops one time and it had quite a sharp, unpleasant bitterness - which probably fits your taste description well. I brewed an English pale ale with Challenger too that had a lot of hops late in the boil and I got the same flavour. I have since realised that whe brewing English ales late hops should not be over the top or you get quite an edge to the flavour. I certainly don't abide by the same rules with American Ales though!!

 

[Trough Lolly]

Or if you reside in SA to perhaps grow one. :lol:
Warren -

[post="126668"][/post]​

:huh: :lol:

 

[Ash in Perth]

thanks trough lolly! Im a chemist so you dont need to worry about going into detail. Still learning to apply what i know to brewing.

Promash does take into account increased gravity reducing alpha acid extraction but i doubt this is very accurate.

The bittering hops (target) are said to have a Alpha/Beta ratio of 2. (Promash data and hoprats). THey are quite new and fresh and i store them at just above freezing temp.

I will try the recipe again once ive built the S/S brewery and i wont have to worry about having too much a large boil volume to chill.

What would be a good hopping scheme for a 23L brew? I love strong hop flavours in IPAs. i want about 65IBU, without getting any polyphenols.

Cheers! Ash

 

[Trough Lolly]

G'day Ash,
I love well hopped IPA's too! 65IBU's is a good benchmark and with a 23 litre batch, it's quite achieveable - and Promash will happily work out an all grain recipe batch of 23L of IPA at 1.060+ OG with 65 IBU's of hopping, no sweat.

A good reference read on IPA's is in the brewing techniques library:
Click here for the article on IPA's...
The article recommends the best English 2-row barley you can buy (which IMHO is Marris Otter) and 1-2% of carapils, which I now replace with Bairds Munich as I like the maltier flavour profile of the munich malt compared to carapils.

I'd say you could use your original hop bittering schedule in a 23L batch. Although the style nazi's will hurl abuse at me, I like a late addition of cascades, but then the contemporary IPA will drift towards an APA with this hop, but hey, you're brewing beer to drink and not slavishly adhere to style guidelines, aren't you?!

Wyeast 1275 - Thames Valley Ale is a good yeast strain, but I personally prefer Wyeast 1028 - London Ale yeast. I'd also recommend 2 level teaspoons of Gypsum in the mash water prior to dough-in, but Canberra water is pretty low profile so your tapwater may differ.

Cheers,
TL

 

[Ash in Perth]

Thanks mate, ill have a look.

What is gypsum exactly? an acidic salt?

According to promash, using just MO and a bit of carapils makes it a bit light for an IPA but 1% pale choc will darken to about 16EBC and adds a bit more character.

Im not too worried about sticking to styles as long as it is close enoguh to be able to enter into the odd competition.

Ill dry 1028 next.

Cheers! Ash

 

[Trough Lolly]

Gypsum = Calcium Sulphate...The food grade stuff - not the Bunnings gardening gypsum - is good for Burtonising your water, if your water is low in minerals. John Palmer suggests that adding Sulphates improves the crispness in the bittering. Part of his article is here... Just don't over do it as sulphate in high dosages can, um, give you the $hits and you'll be spending a lot of time in the throneroom!! h34r:

I like to give the IPA a copper brown tint, hence some 150EBC English Crystal. At least 250g...or around 100g of amber malt for colouring.

Cheers,
TL

 

[Ash in Perth]

I jsut want to say thanks to everyone. After lookig into polyphenols a bit ive decided ill research that for my chemitry project thesis. Ill be looking at how differnent crush sized grains at different temperatures in the mash produce these before and after boiling. I went down to a big well known micro and spoke to the head brewer today about it (who i knew previously) and hes willing to give me a hand aswell.

I dont think i will be looking into the extraction from hops as there is too much involved in this for the time being.

Be a while before i start and finish but ill be going into alot of detail and ill post a summary on here towards the end of the year when its all done.

Cheers! Ash