Premature tails in distillate

[pogriallais]

I'm running into a lot of difficulty recently with my distillation/ fermentation.  The symptoms are early onset of feints/ tails.  I have tried increasing reflux in the still to continue the hearts cut but it isn't working.  I have tried less reflux too.

Fermentation appears to be good.

Grain bill - 100% barley malt

Starting gravity 1.061  Final gravity 0.997. Estimated ABV 8.38%.  Final PH 4.19

Distillation

Still - 250 litre pot with 3 plated column with dephlegmator.

Heads and foreshots are compressed at the begining of the run - 100% reflux for 30 minutes and heads collected slowly afterwards.  Cut is determined by taste a smell.

Hearts- relfux is reduced and heating of pot is increased.  Cut is determined by taste and smell.  The average abv i was collecting before this was 81% ABV.  I can achieve above 81% ABV initially but the abv drops fairly suddenly when about 25% of the expected hearts cut is obtained.  The product becomes feinty after this point.

I have checked the still for leaks but all the gaskets look fine.  Any advice?

[TylerPederson]

Perhaps when you are increasing the heat at the point of your hearts cut you are upsetting the equilibrium that you've created in the still. The increased heat might be prematurely pushing your feints through earlier.

 

[pogriallais]

I have considered this and kept the still in equilibrium to see if it made a difference but unfortunatley not.  I will try it again however.  What I can't understand is how the performance of the still would change so dramatically if I'm doing everything the same for the past 6 months.

[Stumpy's]

What temp did you ferment at, how many hours did you ferment, and did you agitate during fermentation? If you did agitate, was it vigorously? Thinking maybe fermentation temp got a little hot? We have noticed that in the past.

[indyspirits]

I too am curious as to yeast strain and fermentation temp.

[pogriallais]

Yeast strain is Anchor - Active Dried Distillers yeast for malt whiskey saccharomyces cerevisiae.  I use 1g per litre of wort.  Rehydrated using 50:50 wort to water.  I boil the wort prior to rehydrating yeast to kill any bacteria present.  Yeast is rehydrated at 36 C.

Yeast is pitched into wort at 20 degrees C and no temperature control is used.  Temperature reaches 29-32 (max) degrees C.  No agitation during fermentation.

A clear wort is fermented so no grain present.

[MDH]

7 hours ago, MaltMonster said:

Perhaps when you are increasing the heat at the point of your hearts cut you are upsetting the equilibrium that you've created in the still. The increased heat might be prematurely pushing your feints through earlier.

 

Second this. Do a run without increasing the heat as you get into the hearts.

[indyspirits]

9 hours ago, pogriallais said:

Still - 250 litre pot with 3 plated column with dephlegmator.

 

Your fermentation seems well within acceptable limits. I wouldn't rehydrate with wort but that's just me. I always use sterilized RO water and rehydrate in about 10x by weight. I digress...

You're darn near running a pot still.  We used to compress heads & tails with our small 4-tray still but stopped after we realized how much good stuff is in late heads and early tails. Try a full spirits run without compressing heads or holding back tails; trust your senses. Although it may take a bit longer, I think you'll be pleased with the results.