Scaling hops for Mini BIAB

[Drop It Like It's Hop]

I'm looking to try out my first full grain BIAB using Dr Smurto's Golden Ale as a template, however I'd like to use up some leftover Columbus (13.5) hops I have in the freezer (I've also got Simcoe 13 in there as well). I'm looking to scale the recipe down to give a final 9L in the fermenter which will give me a mash volume of around 18L.

Using the BIABacus spreadsheet it suggests that I'll only need to be adding 6g of hops at 60m, then 4g at 10 and 5.
Obviously hop addition weights decrease with volume and AA%, but does this seem correct? If I was to use a combination of the Columbus and Simcoe hops I'd only be adding a few grams of each during each hop addition?

Just doesn't seem like enough hops...

View attachment Biabacus Golden Ale.xls

 

[panspermian]

Take this for an example. If the recipe is designed for 18L, then divide the weight of the ingredient by 18. This is how much you need for 1L. Then times this value by the volume you need like 9L.
Hope this helps.

 

[glenos]

14g for 9L, seems reasonable, roughly 1.5g/L. Maybe a little light on.

Looking at your spreadsheet you missed mentioning the 4g at flameout, bringing you up to 2g/L which is about right, especially with 13%AA, 2.5-3g/L with 9% in that recipe is moderate bitterness.

 

[Drop It Like It's Hop]

thanks for your thoughts - glad to hear my calculations were somewhat accurate. I think I was just thrown off by the fact that my last (kits and bits) batch used 70g of hops to a prehopped tin (nothing over 20mins though) to such a small amount.
Thanks for picking up on the missing hops at Flameout glenos - much appreciated.