PeteB

Recently I ran a post called "Slightly continuous fermentation" Here is another of my techniques that I think is "outside the square" that others may wish to adopt if there are no negative replies. Normally a whisky wash pot still can only be filled to around 85% of its volume to allow for foaming when boiling first starts. Recently I produced too much wash to fit into the still and I didn't want to waste it. About an hour after the foam died down I started to very slowly pump the surplus wash into the still through the drain valve. Also as the spirit was evaporating out, the level in the pot kept dropping so I kept adding wash. There was only a slight amount of foam produced as I added wash. There is a glass inspection hole in my still to watch what is happening. I normally put 500 Litres in, but with this method I can do at least 650 litres of wash and get a much higher output of low wines and alcohol PeteB

I am using a lauter tun to make 100% rye. Rye mash is well known to have very long runoff times because of its viscosity. The lenght of time allows a greater chance of an infection taking hold before the yeast starts. If I put a UV steriliser in the line where the wort comes out of the tun this should greatly reduce the chances of getting an infection in my fermenter. Any experiences, comments or theories would be most welcome. PeteB

Thanks Sage, Just after I posted that question I realised the glycol at the heat pump would probably go below freezing point of water, and as you have said, the colder the circulating liquid, the better the heat extraction.

I think the glycol/water solution in these systems is similar the the antifreeze in a car radiator. Is this correct? If so, why use glycol instead of just rust-inhibitor in the water?

Thanks Denver Distiller. You have given me the confidence to do what other posts have suggested. I don't have a CIP system so I will be using a brush on a long handle. Interestingly I was listening to a radio programme a few days ago on removing stains from fabrics. The speaker said to change the pH on the stain several times by using vinegar followed by bicarb of soda. This is what you are doing in the still:rolleyes: The only question left is what are the concentrations of caustic and citric acid?

I am a little concerned about putting caustic (sodium hydroxide) in my copper pot. I assume the blue deposit on the copper is copper sulphate. Copper sulphate is soluble in water, even more so at around 100C. Copper sulphate plus sodium hydroxide forms copper hydroxide which is INSOLUBLE. If I can wash all the coper sulphate out with water that is good. Insoluble copper hydroxide will probably stay in the still, not sure if that is good or bad. Some copper sulphate is/was in my copper condenser. If that turns to hydroxide I am not sure if it will come out with the spirit as a solid and be filterable or stay attached to the copper forever! Also, citric acid on copper forms a chelate. In water at normal temperatures the chelate slowly releases copper. What will happen next time I run the still? Will the heat dump all the copper into my spirit causing a metallic taste? The above ramblings are just chemistry THEORY. (E&OE it is 40 years since I studied chemistry) A little bit of theory can be a hindrance, but it can make you question a process. Practical suggestions from you out there who have "been there, done that" is the best. Thanks for the help so far.

I will ask the cherry farmer the details and get back to you. The "wash" he delivered to me had some cherry pits and some stalks, but only a small % from the 3 tons of cherries he used. I have read that stalks are not good for some reason, maybe they contain a lot of sulphur compounds! He said fermentation temperature was around 25C (77F) A local distiller suggested that after pressure washing the cherry gunk off, I just run the still with water only. I have done that with 2 small amounts of water and the condensate is now very clear and has almost no taste.

233 views of my post to date and no suggestions on cleaning. I thought this would have been a common task. Further observation: after finishing the spirit run I switched the heat off and left an empty white plastic bucket under the spirit outlet. The next morning the liquid in the bucket was sky blue. it tasted extremely bitter. Typical copper sulphate colour. The fermented cherries did not have SO2 added but I assume there must have been quite a lot of sulphur compounds formed during fermentation. I am sure I will need to scrub the inside of the still before my next whiskey run in a couple of days. Do I get in there with a scouring pad, or vinegar, or bicarb, or caustic?

Hi Dick, Will may come back with a different method from mine. Work out the density of your cordial by using an SG hydrometer (EDIT - I should have said DENSITY hydrometer) I have no idea of the reading but if we say it is 1.0020 g/ml,(Kg/L) then 750 X 1.0020 = 751.5 g per 750 mL bottle or if it is say 0.97453, then 750 mL at 60F weighs 750 X 0.97453 = 730.9 grams Density will need to be corrected to 60 F in USA If you only have a proof hydrometer and it does not float up past the zero, you can still convert the actual reading to density with tables. (the proof hydrometer is reading alcohol plus sugar etc but that does not matter for this calculation)

As some of you would have noticed, I have been running fermented cherries in my pot still. The inside now has a brownish green deposit on it. It is a copper compound, not cherry juice. Any suggestions about the easiest way to remove it, and how important is it to get it all off?

Thanks very much Brian, I should be an expert by the time I absorb all that. I have only had a quick read of the first link by Kinberley Rae, and that is exactly what we are trying to do. I hope there is some info on pot stills in some of the other articles as that is all I have.

It is a NUWEIGH JAC929 Reads 0-150 Kg in 50g steps then 150-300 in 100 g steps, can also readout in pounds

I think this is where you will find what you need to know in USA § 30.44 Weighing containers. Gauging Manual.

This won't help you with your expansion problem, but I find it an easy way to check fill volumes. My bottle filler draws straight from the container that is sitting on a platform scale. Every dozen bottles I record the weight in the container. At the end I divide weight used by number of bottles and that gives me weight per bottle. Then it is a simple conversion of weight (mass) to volume at "standard" temperature. No need to weigh the empty bottles before you start. Temperature of spirit at bottling doesn't matter for the calculation, but the thermal expansion will affect the fill level adjustment. Just bragging here, the last fill test I did with 8 dozen 500 mL bottles I had an average overerfill of 0.03 mL. Probably not enough to wet the cork.

Sorry Brian, I was a bit quick on the post button, I had not nothing to do with the fermentation. The bulk tank of finished ferment was delivered to my distillery. If this lot turns out well for the farmer he will probably produce more next year. Are there any fermentation suggestions I should pass on to him?

No SO2 added. I did read a recent ADI discussion on SO2

I have been asked to distill some fermented cherries for a local farmer. Can anyone give me some advice please. I can get his "wine" through the first distillation in 2 runs in my pot still. I will obviously need to do a spirit run but I have only done grain spirits before. How similar is the spirit run? I assume I make cuts of the fores and feints, but how do I tell where they are? What is the ideal ABV (proof) to start a spirit run? Are there any tricks that are unique to cherries? Thanks, PeteB

Rich, sorry, I think I might have confused you. I was not talking about laboratory techniques to measure ABV or Proof ie by very very accuratly measurement of mass and volume, I do that with a hydrometer and thermometer. I was talking about cutting spirit for barreling or botteling. For this I am weighing between 100 and 300 Kg on platform scales to an accuracy of(I have edited this to correct) 0.05 Kg. So at 100 Kg I have an accuracy of +/- 0.05% which our excise people have accepted. I will also point out that if I tried to weigh only 1 Kg on these scales the accuracy would be down to +/- 5% which is probably not good enough? I must re-read our regs! My scales need to be re-certified every 12 months.

Jake, are your blending vessels small enough to place on platform scales? I don't want to sound rude, but I see why you would like to "measure twice cut once". With your technique you appear to measure about 12 times and cut about 4 times. And from other snippets on this forum I am sure you are not the only one who does it that way. Cutting is so easy on scales. Once I am sure I know the corrected proof of the spirit, I put the numbers into ALCODENS, pour in the calculated mass of spirit then make up to final mass with water. As long as initial proofing was correct I hit spot on every time. If you are a bit wary of overshooting then hold back a little of the water then test the next day. You should find you can then toss the rest of the water in. If for some reason you did put too much water in then it is very easy with ALCODENS to work out how much spirit to add to correct it. Does anyone know if it is possible to put a screen grab into a post? If so, I can show you how to do the calcs. ps I am not an Alcodens salesperson, I purchased a copy.

I totally agree with you Drew. I am sure Will is also a fan of mass measurements. The only volumetric device I use in my distillery is a 60 mL syringe for filling sample bottles. Unless a distillery and its liquids and measuring containers are all at "standard temperature" I think it would be difficult to get accurate measurements. It is possible but not that quick to calculate liquid expansion or contraction, but how does one allow for expansion of the measuring vessel?

An excellent product is stainless WEDGE WIRE mesh. It consists of thin parallel slats that are almost triangular in section. The gap at the bottom is wider than the gap at the top which prevents particles getting stuck half way through the slot. The slats need to be about 1mm apart. The sheets are reasonably rigid so they don't need as much support as the perforated sheets I have seen.

I didn't want to put too much in my first post on this thread, I often have trouble with all my typing vanishing for no apparent reason. Thorough mixing is certainly necessary. And as Delaware Phoenix points out the mixing produces heat, it is exothermic. The mixture slowly warms up then cools again to room temperature. The thermometer and hydrometer will be lagging a little behind, maybe at different rates which would confuse any attempts at corrections. I did a bit more experimenting and did a small dilution in a glass cylinder. I watched closely and noticed each time I stirred the mixture, a lot of very fine bubbles were released. Bubbles in a solution will increase its volume and hence REDUCE its density. But at the same time lots of these bubbles were sticking to the bottom of the hydrometer causing lift, giving the appearance of INCREASING density. Spinning the hydrometer got rid of the stuck bubles but not for long. Also, as Will says above, when diluting ethanol with water, volume shrinkage occurs. ie, 1 litre of alcohol + 1 litre of water equals less than 2 litres of mixture. The next bit is MY THEORY ONLY. IF shrinkage is not instantaneous, the initial volume will be larger which means the density is lower. A hydrometer will sink further, mimicking a higher %alcohol As the volume shrinks gradually the density will increase. MY THEORY ONLY Maybe this is fact! Does anyone know?

My official status on this forum is "Advanced Member" but I am just a beginner. I only had limited experience in other distilleries before starting production in my own distillery 7 months ago. Despite having a science degree and having spent countless hours in a lab, I was becoming very frustrated with variable readings on my hydrometers when measuring the same batch. I eventually noticed liquid droplets sticking to the sides of the hydrometer stem above the liquid level. This would slightly increase the weight, incorrectly indicating higher alcohol. Even though I regularly wipe the hydrometers after use, there was still an oily film preventing liquid running off. I had to thoroughly clean with detergent to get rid of the oil film. With a bit of experimenting I found I was getting up to 0.3 ABV variation (0.6 Proof) caused by the liquid droplets. I now also lower the hydrometer carefully so it won't go much below the assumed reading, that way there is no liquid film on the glass above the meniscus. It is probably very obvious I did not attend distilling school! Are these things taught at distilling school? And here is another trap I found the hard way. When diluting spirit I was finding problems hitting the target. Someome on this forum recently said "blending is a bitch" I WAS in agreement. I know how to do the calculations so I was sure that was not the problem. Recently I added the correct amount of water, I stirred thoroughly and re-tested immediately with thermometer and clean hydrometer. The alcohol concentration was still too high which meant I needed to add more water. Did another calculation and added a small amount of water to correct. When I checked a few days later the alcohol strength was too low! Too much water added. The proof was probably correct the first time. Has anyone else found this problem? Initial enquires suggest the mixture does not stabilise for some time. I now add the calculated amount (by mass) of water and leave for a day or so. I am hitting the target dead centre.

I have been offered free transport back to Australia for a few barrels. Does anyone have and used barrels up to about 25 gallons that they can get delivered to Florida. I could take about 6 depending on size. They would need to be dismantled and plastic wrapped. Thanks, Pete

Hi Coop, how did you determine that you had a Lactobacillus infection? I am asking because I am concerned I may have a similar problem.