Questions about first all grain batch

[BeeGeeBrew]

I brewed an all grain kit from Northern Brewer, the nut brown ale. I built my mash tun from an igloo cooler, and it seemed to hold the temperature well but the temp was a little low.

I used a calculator to determine my strike temp, and it told me 164.5. I heated up to about 165 and dumped it in the cooler. I did dump about a half gallon of hot water in the cooler before this to heat it up. The temp quickly fell to 148 where it seemed to stay. My receipe stated the temp should be 154. What are the negative effects of a mash temp that far below the prescribed one? My efficiency was up over 80% which I was pretty amazed by as well.

I measured my pre-boil gravity and it was 1.038. Using another calculator (based on my boil off since I forgot to measure post boil gravity) My OG should be around 1.050, but the receipe says it should be 1.044. Is this higher OG going to greatly change the final beer?

 

[JLump]

That lower mash temp will have led to a higher proportion of fermentable sugars so you will end up with a dryer beer with less body. Your abv will also be a decent amount higher due to your higher than anticipated efficiency. Nothing to get your panties in a bunch about though.

Welcome to all grain brewing!

 

[theowlman16]

If your target was 154, and you measured 148, why didn't you just add more hot water?

 

[Sailingeric]

You will be fine. My last batch I was a little short on the temp but beer is being made by the yeast as we speak.

Edit- a good read http://brulosophy.com/2015/10/12/the-mash-high-vs-low-temperature-exbeeriment-results/

 

[BeeGeeBrew]

If your target was 154, and you measured 148, why didn't you just add more hot water?

Yeah, I know I should have. I didn't have any extra ready to go though, and I figured by the time I heated more up to near boiling it'd be too late?

I learned next time I'll leave a gallon or so in the pot heating in case I need to add some to raise the temp. Next time I'm also going to raise my strike temp from 165 to around 170...

 

[Hudini56]

No worries, as stated before it will be a bit dryer, less body and the OG and resulting Abv will be higher due to fermentable sugars. But its all good. When I built my new AG brew set up I struggled a bit finding the sweet spot to hold my mash temp (15 gallon keggle looses more than a cooler) My previous set up was a igloo.. I found warming my cooler up with a gallon of water for about 15 20 min prior to mashing in. But 17 deg sounds like a lot. Did you check the temp throughout the mash? My keggle tricks me a bit starting low temp and warms up in 15 min or so and evens out for the duration of mash time. In the end, I bet you will have beer, and it will be more than acceptable..Fun part of brewing. Theres struggles, most of the time we end up with a good beer, thats all YOURS!

Cheers!

 

[Kent88]

It is completely ruined and you should just send it to me

You'll be fine.

 

[Steveg229]

Temperature loss was most likely from the cooler. Your grain temperature and cooler temperature come into play when calculating your strike temp. I always heat my strike water to at least 5+ degrees above strike temperature to account for heat loss from the cooler. Then I leave lids open and wait until the temp drops to strike temperature. Check your grain temp where you store it as well so you can plug that into the calculator. This is the way I do it and am able to hit my temps every time.

 

[oujens]

Temperature loss was most likely from the cooler. Your grain temperature and cooler temperature come into play when calculating your strike temp. I always heat my strike water to at least 5+ degrees above strike temperature to account for heat loss from the cooler. Then I leave lids open and wait until the temp drops to strike temperature. Check your grain temp where you store it as well so you can plug that into the calculator. This is the way I do it and am able to hit my temps every time.

+1 to this. The difference in your temperature appears to be from not accounting for the heat loss from your mash tun. Now you know what this loss is and can adjust on the next batch.