How to modify a recipe?

[matt76]

I've seen @MyQul recommend adding 9% flaked barley to aid head retention.....

Say I've got a 1kg grain recipe - I'd expect to mash with about 3L water, sparge with 4L, and at the end of the boil end up with 5L.

If I add 9% flaked barley do I need to reduce the other grain(s) to keep to 1kg (or alternatively increase the water to keep the grain:water ratio the same)?

Or is it such a small difference that you don't really need to worry?

Reason for asking, I'm currently drinking a very nice black IPA which prompted me to Google, and I found this simple recipe which I'd plan to scale back from 5USGal to 10L but I'm not sure how to factor in the flaked barley:
https://learn.kegerator.com/recipe-dark-forest-black-ipa/

I guess maybe the simple solution is go easy on the water, and then liquor back in the FV if the gravity is still a bit high??? aunsure....

 

[MyQul]

If I was going to add FB to that recipe, I'd keep everything the same but just lower the base malt and add the FB in their (although you may need to add a bit more to hit your OG as the potential extract from FB is lower than base malt by about 6 points)

 

[matt76]

If I was going to add FB to that recipe, I'd keep everything the same but just lower the base malt and add the FB in their (although you may need to add a bit more to hit your OG as the potential extract from FB is lower than base malt by about 6 points)

Oooh, okay, gotcha...

[flicks back to Palmer...]

Makes sense now - you're essentially replacing a bit of one kind of barley for another - both release fermentable sugars but FB is just a bit less efficient so you need to allow for that.

Cool - thanks dude

 

[MyQul]

Yup right. The FB only does two things; adds fermentable sugars and body/head but no big flavour like a specialty malt would so you can kind of treat it like a base malt and replace part of your actual base malt with it