A week ago I ran a 40 liter batch of TFFV with some feints through my still as usual, I still have issues trying to hold back in full reflux with both elements flat out but I don't think that is where my main problem is.(Note. The TFFV did stall and I tried a few things like agitation first but did end up having to add more yeast to get it going again)
After dripping off the fores (320ml) it started coming through with Heads at around 94%, after a couple of 300ml cuts it started to get what I first thought was a tailsy smell but it was still at 94%.The bottom sight glass was a little fogged but it had been that way all through the slow fores collection. With my still I seem to get a better idea of what is going on by looking at the back of the column (if it all is wet, no droplets its good, starts to dry and puddle as tails come in. But the smell now slowly got worse - a yeasty/vomit smell. I just kept going despite the smell the percentages held similar to normal then dropped of and collected down to 20%. I left it a couple of days in the hope it would improve but it didn't and it tasted as it smells. Even after a week or more the smell reduced but the flavor disgusting.
I drained the still out when it had cooled it had the same vomit smell. Pulled down the column, plates very black, plate seals stained tan colour in parts (especially in the grove for the plate).
So far I have washed out the boiler with dishwasher tablet water, soaked plates in diluted StarSan then rinsed then citric and have also given the column SS a good clean.
1) Any ideas on what would cause this and or how to avoid it?
2) When soaking plates in citric should they end up a nice bright copper colour (like new copper) or salmon pink kind of colour?
3) Could the staining within the grove suggest internal vapour leak?
4) Can I re-run the smelly end result or chuck it and start over?
5) Is there more I can do that would further reduce the last of the smell from the boiler and column?
My gear is a FSD 4 plate bubbler on a 50Litre milk can boiler with two 2400W elements.
Thanks All