flower to pellet hop conversion

[louistoo]

how do I convert a recipe requirement for amarillo 5%(dry flower) to my available amarillo that is 8.4% and in pellet form!
please help!

 

[mckenry]

how do I convert a recipe requirement for amarillo 5%(dry flower) to my available amarillo that is 8.4% and in pellet form!
please help!

Download beersmith and learn it.

 

[louistoo]

Right! thanks. no obvious or simple calculation eh. I'm a bit new to computers and downloading this app. was a challenge.

 

[Yob]

Use your thumb, I wouldn't bother and just add %10 less by weight


Pellets are T90?

 

[louistoo]

don't know about T90! I understand that 10% less thing but assume 8.4% aa is almost double the alpha acid content of recipe req. for 5%aa

 

[Blind Dog]

Right! thanks. no obvious or simple calculation eh. I'm a bit new to computers and downloading this app. was a challenge.

Depends on your definition of simple, but in short no.

If you're not too fussed on accuracay, you'll get close using a conversion factor that is the alpha acid % of the flowers divided by the alpha acid % of the pellets (and closer again if you times that by 91% to account for the different utilisation of pellets v flowers)

so if the recipe had 50g of 5% flowers, you'd need about 27g of 8.4% pellets (50 x 5 / 8.4 x 0.91)


(edit: clarity)

 

[louistoo]

don't know about T90! I understand that 10% less thing but assume 8.4% aa is almost double the alpha acid content of recipe req. for 5%aa

 

[louistoo]

clear as mud! 50x5=250 8.4x.91=7.644 and 250 divided by 7.644= 32.7 or did i do that wrong!

 

[louistoo]

Now I get it! thanks everyone.

 

[stux]

My experience is that the AA% only really matters for the bittering additions. Whereas the g/l matters a lot more for the flavour/aroma additions.

I'd use brewing software. Enter the original recipe, note the IBUs, then adjust the hop type and aa%, then adjust the bittering charge to end up with roughly the same ibu

 

[louistoo]

Yeah brew software may save the headaches I guess

 

[Blind Dog]

clear as mud! 50x5=250 8.4x.91=7.644 and 250 divided by 7.644= 32.7 or did i do that wrong!

You did - there's no brackets and multiplication and division rank equally so the equation runs left to right or: 50 x 5 = 250; 250 / 8.4 = 29.8; 29.8 x 0.91 = 27.1

Would probably have been easier if I'd put brackets in. Also shoudl have pointed out that it onyl works if you're adding during the boil not for dry hopping, its more accurate the closer to the start of the boil you add the hops, is affected by gravity etc...

But to be honest unless you're brewing a 'smack you in the face' hopfest I'd be adding 55ish percent of the weight of the stated hops if they're going in the boil (27g of pellets rather than 50g of flowers to follow the example) at the times stated in the recipe, and the same weight for the post-boil hops (if any).

 

[louistoo]

Thanks blind dog,
that seems like rational maths and advice. Much obliged

 

[Jack of all biers]

I was searching old threads about hop flowers/plugs v pellets and found this one. I thought I would bring it back with an answer for future searches.

how do I convert a recipe requirement for amarillo 5%(dry flower) to my available amarillo that is 8.4% and in pellet form!
please help!

There is a simple calculation to do this....

Download beersmith and learn it.

Even if you don't have a beer software (I don't).

Weight of Hops = IBU x (Vol (litres) x 10) / (a/a% x % utlisation)

Or if you want to figure out the IBU of a certain weight of hops; IBU = weight of hops x a/a% x %utilisation / Vol (litres) x 10

% utilisation varies according to the time the hops are boiled, vigor of boil, hop surface area (pellets v plugs or flowers) and Original Gravity of the wort etc but a good guide as published by VicBrew (2002) is below.

For wort 1050 and below;
90 min boil 30% to 28% (I always calculate using the lesser value to be conservative, but I believe the difference is the higher value is for pellets and lower for plugs/flowers)
60 min boil 30% to 26%
45 min boil 28% to 24%
30 min boil 24% to 20%
20 min boil 19% to 14%
15 min boil 15% to 10%
10 min boil 12% to 7%
5 min boil 6% to 3%

For wort gravities above 1050 multply the usual utilisation by;
1060 multiply by 0.95 (ie 60 min boil utl % normally 30% = 28.5%)
1070 multiply by 0.90
1080 multiply by 0.87
1090 multiply by 0.83
1100 multiply by 0.80
1120 multiply by 0.75
1140 multiply by 0.70
1160 multiply by 0.65

 

[Jack of all biers]

Weight of Hops = IBU x (Vol (litres) x 10) / (a/a% x % utlisation)

Or if you want to figure out the IBU of a certain weight of hops; IBU = weight of hops x a/a% x %utilisation / Vol (litres) x 10

I forgot to mention that Weight of Hops is in grams for both equations.