First time decoction mashing

[Pauldoc1031]

So today was the first time I tried a single decotion mash. I did 1 quart of thick mash per lb of grain. I ran into a problem where my decoction did not bring my mash that was sitting at 120 to 150. I did a second decoction to get it to 150. Does it hurt to take more for the decoction then less? Also is there a way to estimate the color after the decotion? I know with the decoction it increases the srm making it darker? And does this effect the pre boil gravity as well as the og so I can properly adjust a recipie for the future? My og was higher then expected but I also have been working on my mash/brew house efficiancy so I'm not sure if that is why my OG was higher then expected

 

[Gnomebrewer]

Taking slightly more decoction than needed is good practice - just add the decoction back in to the main mash slowly, and stop when you reach the intended temperature. The remaining decoction can be left aside to cool to the step temperature, or cooled with a bit of cold water. Alternatively, you could take a smaller decoction and use boiling water to make up the difference if it's needed.

I don't know of a way to estimate the colour from decoction. I find the change to be quite minimal anyway, but the grains used, length and vigour of boil and decoction thickness would all affect it.

Yes, anything that affects OG also must affect pre-boil gravity.
V1 x G1 = V2 x OG
where \
V1 is the pre-boil volume, G1 is pre-boil gravity points,
V2 is post-boil volume, OG is post-boil gravity points.
So expected OG = V1 x G1 / V2
So as long as you know your expected boil off, pre-boil gravity and pre-boil volume, you can calculate your expected OG. Alternatively, Beersmith (probably other software too) has the expected pre-boil volume and gravity in the fermentation tab which should give you an idea of how far you are likely to be over/under by the end of the boil.

 

[Pauldoc1031]

Thank you. So the decoction should not effect the OG?

 

[Gnomebrewer]

Decoctions typically improve efficiency, so yes they will slightly increase OG compared with a non-decoction mash.

 

[Pauldoc1031]

Thank you for the help. I appreciate it. Hopefully next time I hit my numbers a little better