New mash tun, efficiency problems

[lanceburri]

Hi. So I did a 3 gallon batch yesterday with my new mash tun but had two problems: one, if I did my calculations right (which i think I did), I only got about 47% efficiency; two, the wort was cloudy and full of tiny bits when I drained the mash and during the sparge.

I built my tun according to the instructions in this video . The "pipe" is a washing machine hose with the rubber insert removed.

Based on my recipe and the chart in John Palmer's book (double checked with the widget at Brewer's Friend), my pre-boil OG should have maxed at 57.7. 75% would have been 43. I got 25. Just awful. One thing: I measured when the wort was still probably in the 120-130 degree range. Should I have waited until it cooled?

The weird part is, I ended up with a perfect 3(+a tiny bit) gallons after the boil, and my pre-pitch OG was 1.047. I shouldn't have been able to achieve that OG after a one-gallon loss, even at 100% efficiency.

So what the hell?

One thing that I know I can improve on: my mash temp dropped from 153 to around 145 by sparge time, even though I added two quarts at 170 halfway through.

I can add details about my recipe, etc., if need be.

On the cloudiness, I wonder if I should have let the debris settle and then siphoned it before pitching. Not really worried about oxidation at that point, so why not? But it's still troubling that it was that cloudy at all.

Any advice?

 

[Genuine]

What are you using for brewing software and can you post the recipe?

 

[Chris Grubb]

Did you filter your runnings? Meaning before you drained the wort from the tun to the brew kettle, did you capture some wort slowly and add it back to the tun until the wort cleared?

 

[seatazzz]

What Chris G is describing above is basically lautering - loosely defined as helping the grain bed settle before draining the first runnings. Doing this should keep some of the 'bits' out of your wort as the lighter husks and bits will settle to the top of the grain bed, creating their own filter. If you're using gravity alone (no pump) it will take a bit longer. Once your mash is done, drain about 1/4 to 1/2 gallon of your wort into a heat safe glass pitcher or some other vessel that can easily be poured from. Add that back to the top of the mash, drain, and repeat until your wort runs out clear. At that point you can drain your wort into the kettle.

 

[lanceburri]

What are you using for brewing software and can you post the recipe?

Not using any software. The recipe is:
5 lb. Pale Malt
0.6 lb. 90L
0.3 lb. 80L
0.3 lb. 40L
.25 oz. (7 g) Centennial 10.4% 40 minutes
.5 oz. (14 g) Mt. Hood 5.6% 20 minutes
¼ tsp. Irish Moss 15 minutes

That's for a 3 gallon batch.

Did you filter your runnings? Meaning before you drained the wort from the tun to the brew kettle, did you capture some wort slowly and add it back to the tun until the wort cleared?

Yeah, I did that a quart at a time, 10 times, and it looked exactly the same the 10th time as the 1st, or so my assessment was.

I was just using gravity, as seatazzz mentioned. Should I have just kept going? Everything I've seen about lautering, it only should take a few times.

Could my barley have been ground too finely? I just used the grinder they have at the brew store.

Thanks for the replies.

 

[Brewsit]

Grind could have been too fine, what you ideally want to see is the grain split into about 3 pieces and the husk remains intact. If you have a shredded husk or too fine of bits they will just continue to run through the mesh. With that small of a batch you might not have had a deep enough grain bed to really seat it well... if your mash is wider than it is tall you might have issues, in my experience. You might be having efficiency issues due to the way the screen works... if it's not all the way at the bottom, you will lose all the grain that settles underneath it, as the fly sparge method (I'm assuming you're using it?) means the weight of the fresh water on top pushes the sugars (which are heavier than water) through the grain bed and out the bottom. False bottoms work well for this because you are sucking the wort from the lowest point you can. You can also lose efficiency if you went too fast, creating channeling. If your sparge takes 45 min - 1 hour you should be fine there. Any of that sound plausible?

*Edit - something I overlooked. You added two quarts of water to the mash, further diluting it... this could have a small impact too. On a batch that small, it would raise your mash from a thickness of 1.25 quarts per pound to 1.5 quarts per pound. Not a problem, but you might have wanted to run off more liquid and boil it down further to get the efficiency you wanted.

 

[RM-MN]

Hi. So I did a 3 gallon batch yesterday with my new mash tun but had two problems: one, if I did my calculations right (which i think I did), I only got about 47% efficiency; two, the wort was cloudy and full of tiny bits when I drained the mash and during the sparge.

I built my tun according to the instructions in this video . The "pipe" is a washing machine hose with the rubber insert removed.

Based on my recipe and the chart in John Palmer's book (double checked with the widget at Brewer's Friend), my pre-boil OG should have maxed at 57.7. 75% would have been 43. I got 25. Just awful. One thing: I measured when the wort was still probably in the 120-130 degree range. Should I have waited until it cooled?

The weird part is, I ended up with a perfect 3(+a tiny bit) gallons after the boil, and my pre-pitch OG was 1.047. I shouldn't have been able to achieve that OG after a one-gallon loss, even at 100% efficiency.

So what the hell?

One thing that I know I can improve on: my mash temp dropped from 153 to around 145 by sparge time, even though I added two quarts at 170 halfway through.

I can add details about my recipe, etc., if need be.

On the cloudiness, I wonder if I should have let the debris settle and then siphoned it before pitching. Not really worried about oxidation at that point, so why not? But it's still troubling that it was that cloudy at all.

Any advice?

If you used a hydrometer at the high temperature you reported it won't be accurate. There corrections for that but the best is to take time to cool it to the right temperature.

Clear wort isn't necessary to get clear beer. Many brewers obsess over getting clear wort. What you want is to lauter until big pieces of husk are no longer present. Little bits, don't worry. You should see the wort that we BIAB brewers start with. We still get clear beer.