Terrible Efficiency.

[IslandLizard]

I read though this, sounds like progress is being made. I did not notice if anyone mentioned the iodine test(pharmacy type iodine turns dark purplish in presence of unconverted starch) to see if conversion was completed. Every time I have checked my mash with it, have had full conversion, so I don't do it much anymore, but it is a useful tool to rule that aspect out.

As someone mentioned above, paying attention to enzyme potential of grain bill also important.

That's a really good point on checking conversion completion with Iodine.
I bought a small, 1 oz bottle of it in the Homebrew store for a buck a few years ago to do the same test. I've been disinfecting minor scrapes and wounds around the family with it too.

The OP is using Belgian Pale Ale, which may be a bit undermodified, as good Belgian Ale malt should be, but with enough DP to convert some adjunct, at least 30%, possibly higher, up to 50%.

 

[IslandLizard]

I think the main problem lies in the OP's mash tun, leaving a much larger volume of high gravity wort behind after lautering. He needs to be able to drain his mash tun completely to get to typical efficiencies. I already suggested using a voile bag as a filter to eliminate the deadspace in a simple way. Buy some voile curtain material and sew a bag from it. Done! BIAB in a dedicated mash tun...

Fly sparging make no sense for vessels that can be stirred manually.

 

[doug293cz]

I read though this, sounds like progress is being made. I did not notice if anyone mentioned the iodine test(pharmacy type iodine turns dark purplish in presence of unconverted starch) to see if conversion was completed. Every time I have checked my mash with it, have had full conversion, so I don't do it much anymore, but it is a useful tool to rule that aspect out.

As someone mentioned above, paying attention to enzyme potential of grain bill also important.

Not a fan of the iodine test myself. The residual starch in a mash is almost all in the grits. Once starch is dissolved in the wort it converts very quickly, so it's easy to find no starch in the liquid, while the grits still contain significant amounts of starch. To get a good iodine test, you really need to crush up some grits in the sample. I've seen comments to the effect: "I don't sample the grain because it always tests positive for starch."

A better check of conversion completeness is to measure the SG of the wort in the mash (after a good stir.) The end of conversion SG is mostly a function of the mash thickness, so you can use the table here to compare your SG to the max you could get at 100% conversion. You can also use this method to calculate conversion efficiency separate from mash and lauter efficiency.

Brew on

 

[eric19312]

A refractometer and accurate volume / grist measurements are pretty helpful in diagnosing issues with efficiency. If you know your strike water volume accurately and gain weight accurately you can calculate the SG that correlates with 100% conversion efficiency. Then starting at about 45 minutes into mash test the wort and see how close you are to 100%. When you test give it a stir. If you are losing too much heat testing and stirring you can pull out quart or so and heat that on stove top and add it back in. This is sort of like doing a decoction but just doing enough to replace heat you lost. At this point dialing in exact mash temperature is less important that being in reasonable range.

I've found on my system I generally need a bit longer than 60 min to get full conversion. My 90 minute mashes always get me pretty high efficiency.

 

[IslandLizard]

Not a fan of the iodine test myself. The residual starch in a mash is almost all in the grits.

A proper starch conversion test IS on the grits. I know, most do it the easy/wrong way, on the liquid, which renders the test useless.

 

[IslandLizard]

I've found on my system I generally need a bit longer than 60 min to get full conversion. My 90 minute mashes always get me pretty high efficiency.

Have you tried milling finer? I get no benefit from mashing longer than 60', but I do mill quite finely on a 0.034" gap (0.026-028" for wheat, rye, and flaked goods). Mash efficiency is 82-87% easily.

 

[eric19312]

Have you tried milling finer? I get no benefit from mashing longer than 60', but I do mill quite finely on a 0.034" gap (0.026-028" for wheat, rye, and flaked goods). Mash efficiency is 82-87% easily.

I have and on my system efficiency was improved with a somewhat coarser crush. I do continuous recirculation and it may be that the finer crush lead to grain bed compaction and channelling. The coarser crush also makes for a very relaxed mash. Tight crush I have to keep close eye on recirc rate to avoid sticking. Typically once I dough in I will spend the mash time packaging previous batch. My keg cleaning, purging and closed transfer is relatively time consuming but between the longer mash and the fly sparge it is not that big of a deal to have it done by time I am done sparging. Then I can harvest yeast, clean and sanitize the fermentor during boil. Yes my brew day could be shorter but either I would then need a different day for packaging or have to rush through every step increasing potential for mistakes.

Also my longer mash benefits more than efficiency. For a highly fermentable wort I like a Hochkurz mash with steps at 144, 160 and 170F. Takes about an hour and 45 minutes including step rise times but makes a fantastically fermenatble wort.

 

[brewbama]

I have and on my system efficiency was improved with a somewhat coarser crush. I do continuous recirculation and it may be that the finer crush lead to grain bed compaction and channelling. The coarser crush also makes for a very relaxed mash. Tight crush I have to keep close eye on recirc rate to avoid sticking....

This would be a great example of Darcy’s law for laminar flow through sediments. There is a balance point/point of diminishing returns for a finer crush before channeling around the mash occurs.