Definative answer required

[Vossy1]

I'm very confused ...nothing new there I here you say

I need a definative answer with regard to hop substitutions.
I'm looking to brew M.Ollossons Old Rambler this weekend.
The receipe uses 109g EKG 4% AA giving a IBU of 35 in 23 ltrs
M.Ollosson writes to work out a hop substitution

weight of original hop x it's AA content / new hop AA = new hop weight.

My EKG are 5.6% AA so the new hop weight should be 77.9g ish.

However Brupaks say to work out the hop weight it's

EBU req x brew length / AA x 2 which gives me 71.9g

And to top things off beersmith gives another set of figures based on 3 formulations.

Help I'm getting bogged down on this

[UserDeleted]

You are right with regard to hop substitutions.

Brupaks method is a simple way of determining hop amounts based on a recipe you are designing or altering.

The other three methods in Beersmith I would guess are Tinseth, Rager and Garetz. Again they are used to determine the estimated IBU level produced by a given qty of hops or alternatively what qty of hops are required to produce a given IBU level.

To substiute one hop for another with a different IBU use the standard formula

weight of original hop x it's AA content / new hop AA = new hop weight.

[Jim]

Sorry, no definitive answer, but basically the differences are down to what utilisation is assumed. Most often, 20% is a reasonable assumption, but it varies with boil time, gravity of the wort, the actual quantity of hops, and probably fifty other things I haven't thought of.

Mark Olloson's recipes assume a particular utilisation and if you really want to mimic them, use his substitution formula. AFAIK, most beer calculation software tries to take account of some of the other factors that affect utilisation, so giving a theoretically more accurate result.

However, unless your equipment yields the same utilisation, you won't get the theoretical IBUs anyway, so (in my view) don't bother about a few grammes here and there. Learn how you like your brew made in your own equipment and aim for consistency.

[UserDeleted]

Sorry, no definitive answer

But there is a definitive answer with respect to hop substitutions! If I brew one of my recipes on my brewery with 100g of hops at 4% AA, and the next time I brew I have hops at 2% AA then I need to use ( 100 * 4 ) / 2 or 200g.

Of course as you say most recipes asumme a utilisation figure and calculate weights of hops required based on that. Unless you know the utilisation figure for your brewery then the chances of producing the exact same beer is slim, with time and repetetive brewing of the recipe you can tailor it to you brewery.

[Jim]

Sorry, no definitive answer

But there is a definitive answer with respect to hop substitutions! If I brew one of my recipes on my brewery with 100g of hops at 4% AA, and the next time I brew I have hops at 2% AA then I need to use ( 100 * 4 ) / 2 or 200g.

Of course as you say most recipes asumme a utilisation figure and calculate weights of hops required based on that. Unless you know the utilisation figure for your brewery then the chances of producing the exact same beer is slim, with time and repetetive brewing of the recipe you can tailor it to you brewery.

I meant to the general problem of IBU calculations, of course.

[Vossy1]

Thanks guys that's that one put to bed

My next question is for the Beersmith users.

I'm inputting Ollosson's receipe's into Beersmith and now I know that I can ignore the IBU to some extent I'd like to ask a question about efficiency.

I'm averaging over 80% and Ollosson's receipe's assume 75%.

Can you use the efficiency to change the quantities of ingredients required on Beersmith, ie, input the quantities at 75% then by changing the efficiency figure to 80% will it lower the quantities of ingredients required

[eskimobob]

Can you use the efficiency to change the quantities of ingredients required on Beersmith, ie, input the quantities at 75% then by changing the efficiency figure to 80% will it lower the quantities of ingredients required

Yep - Just put the recipe in using 75% then once it is in, hit the scale button and enter your efficiency - all the ingredients will be adjusted accordingly.

[Vossy1]

Thanks EB

I knew I could I just didn't know how

I'm getting pretty close to being able to use my system with some competence at the mo. A few more brews and we'll have to sort a date out

I've just got to sort the sanitising of the plate chiller. My 1st brew using the chiller is fine so the sanitising worked, however I'm would still prefer to sanitise by boiling.

Would o-rings be alright to boil IYO

[Vossy1]

When using beersmith and you can't find an exact style match, is it best to create one or go for a matching OG