Low Original Gravity

[Robert Mulcahey]

Evening guys and gals! Been coming here for a while for brew tips. First time posting.

I went to start a batch of Irish Red following this recipe:

9lb Munich
2lb Vienna
.25lb Roasted Barley
.75lb Crystal 150L
1oz Chinook Hops at 60 Min
1oz Fuggle Hops at 15 Min
Mash 155 F (no pre-heat on the mash tun)

And as you may have guessed from the thread name my pre-boil gravity came in at about 1.020. Now I added 2lb of light DME to the boil to bring it up over 1.040 a bit. What I'm trying to figure out is what I did wrong here. First time running into a problem like this. Any advise you guys can offer would be fantastic.

Thanks!

 

[JimRausch]

The most likely possibility is a poor crush. The 2nd most likely is an incorrect measurement. Or maybe the two should be switched in order.
And congratulations on your 1st post! Good bunch of folks here.

 

[JimRausch]

Also good job on having some DME. I always try to keep a couple lbs. DME and a couple lbs. honey or sugar on hand just in case.
An example- my last brew- the Redrum, I only got a mash efficiency of 54% where my usual is more like 70-75%. I didn't notice until after I was cleaning up that the thumbscrew on my mill had slipped and my crush was poor. I had to add all the DME I had (2 lb) and another 2lb of honey to get me up to where I wanted to be. I reset the mill setting when I crushed tonight getting ready for tomorrow morning. Should have noticed the crush last time, but I guess I hadn't had enough coffee yet.

 

[CascadesBrewer]

Evening guys and gals! Been coming here for a while for brew tips. First time posting.

I went to start a batch of Irish Red following this recipe:

9lb Munich
2lb Vienna
.25lb Roasted Barley
.75lb Crystal 150L
1oz Chinook Hops at 60 Min
1oz Fuggle Hops at 15 Min
Mash 155 F (no pre-heat on the mash tun)

And as you may have guessed from the thread name my pre-boil gravity came in at about 1.020. Now I added 2lb of light DME to the boil to bring it up over 1.040 a bit. What I'm trying to figure out is what I did wrong here. First time running into a problem like this. Any advise you guys can offer would be fantastic.

Thanks!

Hmmm...5 gal? That looks more like a 1.060 ish grain bill. What was your mash process and temps?

 

[Robert Mulcahey]

Smooth job on my part, didn't give size. Starting with a smidge over 6 gallons of water pre-boil.

 

[RM-MN]

Vienna malt is low on diastatic power and Munich may have little to none, depending on the maltster. You may have just had too few enzymes to complete the conversion. Look at the diastatic power of the malts you used to see if this is the cause. In the future, adding a bit of pale malt might be in order.

 

[Soulshine2]

Evening guys and gals! Been coming here for a while for brew tips. First time posting.

I went to start a batch of Irish Red following this recipe:

9lb Munich
2lb Vienna
.25lb Roasted Barley
.75lb Crystal 150L
1oz Chinook Hops at 60 Min
1oz Fuggle Hops at 15 Min
Mash 155 F (no pre-heat on the mash tun)

And as you may have guessed from the thread name my pre-boil gravity came in at about 1.020. Now I added 2lb of light DME to the boil to bring it up over 1.040 a bit. What I'm trying to figure out is what I did wrong here. First time running into a problem like this. Any advise you guys can offer would be fantastic.

Thanks!

need more info on what you did ...do you take good brewing notes? Batch size, pre-boil volumes, mash temp,etc,etc. You should be up past 1.050 without adding the DME

 

[CascadesBrewer]

Vienna malt is low on diastatic power and Munich may have little to none, depending on the maltster. You may have just had too few enzymes to complete the conversion. Look at the diastatic power of the malts you used to see if this is the cause. In the future, adding a bit of pale malt might be in order.

This might be the answer. I guess all my all-grain batches have had plenty of pale malt that I never had to worry about this topic. It seems like light Munich should have plenty, but it looks like darker Munich can be low. OP should check the spec sheets for the maltster (this info is generally available).

http://beersmith.com/blog/2010/01/04/diastatic-power-and-mashing-your-beer/

 

[ccous]

Shouldn’t Vienna and light Munich be able to be used as base malts (on their own?). Plenty of diastatic power I always thought, and never had a problem myself. Sounds like maybe mash temp was higher than intended and/or poor crush as mentioned?

 

[ong]

Shouldn’t Vienna and light Munich be able to be used as base malts (on their own?). Plenty of diastatic power I always thought, and never had a problem myself. Sounds like maybe mash temp was higher than intended and/or poor crush as mentioned?

Some Munich only has 20-25 °L DP, which isn’t enough to self-convert, let alone convert any adjuncts.

I’ve done Munich SMaSHes with light Munich, but it’s a slower mash than usual, and a little fussy.

 

[Miraculix]

From my humble opinion, Vienna and Munich are not exactly what would be used traditionally in an Irish red.

Pale malt as the base, maybe some adjuncts like flaked wheat or barley or oats, up to about 5% Crystal and a little bit roasted barley for the color.

Certainly no American hops, only bittering additions, maybe small aroma additions for flavour. English or noble hops should do the trick. Hop aroma shouldn't be overpowering and noble in character.

Clean and good attenuation yeasts and you're good to go.

 

[Lefou]

Some Munich only has 20-25 °L DP, which isn’t enough to self-convert, let alone convert any adjuncts.

I’ve done Munich SMaSHes with light Munich, but it’s a slower mash than usual, and a little fussy.

I've had the same issue when using certain malts even at lower mashing temps with a fine grind. The work-around was adding a bit of amylase, pilsner, or wheat malt and adjusting the mash in order to speed things up slightly.