What am I doing wrong?

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_jon_

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I am brewing today and I've got the mash rest on at the moment. I missed the mash rest temp by 4 degrees c. I didn't think it would matter too much... but almost an hour and I just checked the gravity. It's coming in at 1.050 and I was aiming for 1.065! Miles off and I actually slightly went over my grain bill because there was a bit left in the bag. Not much.. but I'd expect to hit my 1.065 at least?

My recipe was calculated with 70% efficiency, but it looks like it's actually a lot less.

I've not taken it out of the mash tun yet, the hour buzzer is going as we speak. Should I leave it in the mash tun for longer or will the temp have dropped too much to get anymore sugars out?

Also, should I be testing the OG directly from the mash tun?

As I think about it, it's not the end of the world as I was aiming for a late 6 early 7 % IPA. So with this rubbish efficiency it might settle at about 5.5-6% which is respectable.

That said I would like to get to the bottom of why my efficiency is so bad and I'm missing the OG by so much. Could it be those 4 degrees?
 
What temperature were you aiming for and what temperature is it at now? I don't check og from the mash tun as the boil is going to change it anyway due to evaporation aso it will effectively increase. I would probably go with it now and see what it comes out at after the boil and cooling, you may be closer to your target. The temperature of the mash will affect how much fermentable sugars you get but it tends to be higher temperatures that produce less fermentable sugars.
 
A few things, have you temperature corrected the hydrometer reading, have you calculated what the post mash SG should be? I don't take a gravity reading until after the sparge, if you know what that should be based on the volume and expected OG then you should have an idea if you are on target.
 
Ah I see what I've done. I got the sparge volume and strike volume mixed up.

I needed 18L for Sparge and 16L for strike. And I used 18L for strike water.

But good point regarding checking now, should check in the boil kettle before I turn it on.

I used a refractometer and thought you didn't need to temp correct them?
 
Maybe it's just me, but I believe the OG is the SG of the wort into the FV, rather than the mash SG?

The SG from the mash will increase a nice amount just from boiling, thanks to the boiling off reducing the volume and increasing the concentration.

So until you've boiled and transferred to FV you don't have the OG. Once you have boiled, cooled and transferred, check your SG again. If it's still a fair bit under target just use some dried malt extract to adjust to target (you should be able to find an online tool to calculate how much you need to use).
 
Ah right... thanks for explaining it. I understand now :) And I'm less panicked.. I read it again when I transferred to the boil kettle and it was 1.051. I'll remember to test after the boil, and see what I've got then.

Also, point taken about the 4 degrees. I need to pay closer attention to my mash temp. Or get a hermes to raise it if needed.
 
Yeah, mash temp messed up my first AG, a saison. I struck at 72 degrees (as so many advise on here..) rather than calculating strike temp using temp of grain etc, and been a beginner didn't twig that mashing at 68 degrees C would leave me with too many un-fermentables for the style... :lol: But heh, it's nice beer. I also fell well short of the target OG, and had to add DME.

The same will be true of yours, even if the OG comes out a bit low. You will still have a nice tasty beer to drink, and that is what matters. It's far too easy to become to concerned about efficiency, targets etc. I didn't even bother for my last AG (wheat beer), just measured the post boil SG, the SG into FV (OG) as I diluted, and I'll record the FG so I can calculate the % ABV (it's hit 4.2% already). So long as you don't have feline urine or off flavours, meh it's beer. :thumb: It'll still probably taste better than commercial stuff, cost a lot less AND the best bit is you made it yourself.
 
In this instance, rather than playing with the DME I may just leave it as it is, I was aiming for a high % beer anyway for the new year... but I'm happy to settle for the same beer a bit weaker. Luckily I wasn't aiming for 4-5%, as it would have ended up too low. I was shooting for 7% so it should settle around 5% at this rate I suspect.

I need to learn more about mashing temperatures.. as I always strike at 68c regardless of style. I have a brewing course booked for the new year, hopefully I'll learn some more stuff :)
 
I am having problems with an ESB brew that I was very successful with this time last year. For an 80 litre batch I used about 50 litres of mash water, 15l of sparge and topped up the boiler with about another 20l to allow for boil off. Unfortunately, the temperature controller that activates my herms pump went on the blink and did not switch on when the mash temp fell below the set point of 66C. When I stuck a digital thermometer in the top the mash the temp was down to 57C. I went on to do the boil and transferred the wort to the FV. OG was only1016 - well below my last batch (1050). Fermentation seemed to go ahead though so after a couple of weeks I transferred the beer to my maturation vessel where I normally leave it to naturally clear before conditioning in bottles and pressure barrels. However, after more that 2 weeks the liquid is still very cloudy and tastes watery. FG is 1010. I suspect that the cause of the problems was too low a mash temp, plus perhaps too little sparging. I am in two minds whether to chuck it all away and start again or try to condition it into something drinkable. All suggestions would be welcome.
 
That's quite an operation there.. far more advanced than my 2 coolers and a boiler.

I think I should organise a hermes though, as that would have saved me today. Sounds impressive that you have the hermes come on automatically if the temp drops (usually anyway lol).

I'm a closet brewer.. (hmm..), I don't have an area to brew all the time, I have a utility room which is only big enough to store my brewing equipment. I have to brew in outside the utility in the hall and then put it all away again when I'm finished. So a permanent setup isn't an option for me.
 
Hi!
You should perhaps consider a mini-HERMS coil in a kettle controlled by an Inkbird. It takes up very little space.
See post 3 here: http://www.thehomebrewforum.co.uk/showthread.php?p=721604&highlight=HERMS#post721604
That's not my equipment, by the way - I found the photo online. I reckon the coil does not have to be "plumbed in" to the kettle - a mini-cooling coil would work. If the kettle was plugged into a voltage regulator the water would be heated more "gently" and it would be easier to control the mash temperature.
Of course, you are going to need a pump to get the wort moving around the system.
 
That's a brilliant idea :) I might look into that.

Well this brew day was a disaster. No idea how I've ended up with just over 12L in the FV @ 1060. When it was supposed to be 23L in the FV at 1068!! What a disaster. I think I need to recalculate my boil off and water amounts.

I've already added yeast as my original intention was "oh well I've got 12L of rocket fuel :)" - Is it now too late to boil some water, cool it and add it to dilute it down and increase the volume? Maybe if I add about 5L it won't decrease the SG too much and I'll get almost a full keg.

What are your thoughts?
 
Hi!
EDIT
Using BeerSmith, adding 3 litres of water should give an ABV of 5.1%, adding 4litres will get an ABV of 4.8%. This drops to 4.4% if you add 5 litres of water.
These are based on 81% attenuation, advertised for US-05.
 
That's great.. I've got beersmith, but not played with it too much yet. I must learn how to work that out :)

I think I'll throw 4 litres in and have a steady session IPA.
 
I've been a bit delayed as I had to go away for a couple of days. The beer is still sitting in the FV at 12 Litres. I would like to add the 4 litres of water to it, but it's bang in the middle of fermentation and still has a crausen. Should I wait to add the water? Or can it be added at any moment?
 
The ABV is no huge concern, as I was aiming high anyway. I think 16L of 4.8% ale isn't so bad. Will be a nice session ale to demolish over new year period.

But can I chuck the water in anytime? Or should I wait for fermentation to end?
 
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