Phenol ??

Steve SPF

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Took two brews out of fermenters this week and both had a distinct 'tinny' flavour, seemed to fit for 'medicinal' as well but more tinny for me.

I like to think that hygiene is pretty good. I clean everything in sight with a caustic solution now, rinse, then rinse with a sodium metabisulphate and then sanitise before use.

I'm curious about the water. I'm aware that phenol flavours can be water related and I'm just wondering if that's what got me. I have been harvesting and re-using cooling water for a while now but it is tap water and it is chlorinated. I haven't really delved into water chemistry yet so am simply treating the water with sodium metabisulphate before use.

Any thoughts? The answer isn't RO water by the way, just not practical.
 
When you say "re-using" you mean you're holding water that's gone through your chiller and using it to brew with? Taste the water before you get started. It could have picked up any number of flavors from tubing, hoses, copper tubing, chiller plates, storage container. I'd start with fresh, filtered tap water for mashing liquor and re-think how you recycle your cooling water.
 
I kind of trust that process, although always open to suggestions.

It goes through food grade hoses all the way from the tap, through a stainless cooling loop or a caustic cleaned/sanitised plate chiller and then into a stainless holding vessel. Been doing that for a little while and haven't picked anything up before.

I'm typically using 100lt of tap water to cool with. Initially I was having to just drain that away but it sits really badly with me, it's important to be as light touch as I possibly can be environmentally; all that waste water felt like a real sin.

I am suspicious of the water but of the make up of it as it's coming out of the tap.

Typical water PH is 5.4, as is typical Mash PH.
 
I use cooling waste to water the garden and plants. We virtually always need that around here.
Have you considered recycling your cooling water by simply pumping it back through your chiller when the time comes rather than using new tap water for cooling and old water for brewing. If you had 2 containers of whatever size you use to hold your cooling waste, on brew day you can drop a frozen water jug or two in your cooling water, pump it through the chiller (I've used a cheap pond pump) and catch the flow in the second container. Repeat ad infinitum.
It may not be the source of your current off flavor, but I'd want to brew with fresh water no matter what.
 
Chlorine can lead to off flavors in beers. You either need to run it through an active carbon filter to remove it or treat the water with metabisulfite. The other source of phenol is in the fermentation. Some yeast such as Belgian, wheat or English strains can produce phenol off flavors. I have got it from English strains when I under pitched with low oxygen levels in the wort. Another source is a wild yeast infection. The most likely source is the chlorine in the water, the least likely is wild yeast.
 
I use sodium metabisulphate, it's the only wtaer treatment I do use at the minute. Maybe I didn't use enough this time, I can't see that but it's definitely a possibility.

I'm honestly wondering if there's more chlorine in the water at this time of year, due to the heat maybe, or due to the lockdown somehow. Is there a reliable test anywhere for chlorine content?

I'm going to look at carbon filters for sure, that should be relatively simple.
 
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Around here they definitely treat the water differently at different times of the year. Between carbon filtration and Campden tabs, it seems to be fine for me. When I've gotten specific medicinal, it's attributable to infection/wild yeast. Never had any problem with chlorine.
 
Carbon filters may help but they might not remove as much chlorine/chloramine as you think, unless you are extremely patient. I found this in a post from Martin Brungard on HBT forum:
If your water contains chloramines, consider the use of metabisulfite as your primary removal option. As mentioned above, using activated carbon filtration to remove chloramine requires a very slow flow rate. For instance, the flow rate through a typical 10-inch undersink cartridge would require that the rate be less than 0.1 gal/min. That makes metabisulfite treatment much quicker and the effect of the metabisulfite addition is negligible on water quality.

Like JA I let my cooling water drain onto the grass/trees/plants in the back yard. I first put drain it into a yard-waste bucket so the initial hot water doesn't kill the grass...actually grass, clover, ground ivy, etc.
 
Around here they definitely treat the water differently at different times of the year. Between carbon filtration and Campden tabs, it seems to be fine for me. When I've gotten specific medicinal, it's attributable to infection/wild yeast. Never had any problem with chlorine.

I'm looking at the water thinking something changed so maybe that's it. Is there such a thing as too much sodium metabisulphate? If not I will triple the dose and see how we go; not like it's expensive
 
Like JA I let my cooling water drain onto the grass/trees/plants in the back yard. I first put drain it into a yard-waste bucket so the initial hot water doesn't kill the grass...actually grass, clover, ground ivy, etc.

I owned/edited a beer magazine a couple of years ago and one of my favourite articles was around sustainability. I spoke to several brewers, all of who I really admired, who refused to compromise on this stuff and worked hard to find a way to get it done. I bang the drum quite loudly now around sustainabilty and really want to find a way of being true to that; and make decent beers obviously!

Traditional brewers that I speak to talk about using 8-10 pints of water to produce a pint of beer, I'm gobsmacked at that; had no idea. i really, really want to be more efficient than that.
 
The tap water where I live is really good, and the chlorine content is very little... had the water company come out and test it for me for chlorine.
I built my own system for water filtration, just to be sure everything is good. I use a three filter in series system.. first is a particulate filter, followed by an activated carbon filter then finished off with another finer particulate filter... the flow rate is important, not to flow too fast through the filters, to get the best action of the carbon. I am on the conservative side, but flow 1.5 to 2 liters per minute. It does take a while to fill the mash tun and liquer tank prior to brewing.. but that isn't a concern because there are always other things to do while filling.
I don't remember the micron size of my filters, but I do use a coarse micron for the first particulate filter and a finer micron filter for the final... important to keep carbon particles from flowing into the brew water.
No wast water created as with an RO system.
 
I owned/edited a beer magazine a couple of years ago and one of my favourite articles was around sustainability. I spoke to several brewers, all of who I really admired, who refused to compromise on this stuff and worked hard to find a way to get it done. I bang the drum quite loudly now around sustainabilty and really want to find a way of being true to that; and make decent beers obviously!

Traditional brewers that I speak to talk about using 8-10 pints of water to produce a pint of beer, I'm gobsmacked at that; had no idea. i really, really want to be more efficient than that.

Steve, I really applaud your commitment to sustainability. I hope my water-the-lawn post didn't imply otherwise. The more you, and others, mention sustainability, the more it seeps in to my consciousness.
 
I have a 60 gallon drum I use for chilling with a pond pump on my IC. It works pretty well for 5 gallon batches, with a small fridge i was able to make into a fermentation chamber I have extremely low water waste these days.
 
If your water is treated with chlorine and you're chilling with it, then saving it, that water is most likely no longer chlorinated. I don't think treating will hurt, probably not necessary though unless you're adding more tap water.
Just out of curiosity, what are you sanitizing with? Bleach and iodopher can lead to off flavors if not properly used.
 
There's a member here that had a similar problem with a particular beer that I tasted several years ago. After chasing every possibility, someone suggested that algae could impart a medicinal taste. He was using well water and part of the plumbing. I believe to an in line carbon filter, was clear vinyl tubing. Turned out that there was algae in the tubing. It was the problem. Whooda thunk it?

If the water you're saving is exposed to light for any period of time, that is a possibility. Likely among the last I'd look into, but a possibility nonetheless.
 
There's a member here that had a similar problem with a particular beer that I tasted several years ago. After chasing every possibility, someone suggested that algae could impart a medicinal taste. He was using well water and part of the plumbing. I believe to an in line carbon filter, was clear vinyl tubing. Turned out that there was algae in the tubing. It was the problem. Whooda thunk it?

If the water you're saving is exposed to light for any period of time, that is a possibility. Likely among the last I'd look into, but a possibility nonetheless.

Bob is on something not addressed in this thread before. Whenever you introduce air to water you are looking for possible contamination also. I have been a part of maintaining a small residential water system for 20+ years. The testing we do is very stringent. The chances of water that has been sitting around in a open vessel or exposed in any way to air only would have a slight chance passing a coliform test. Coliform tests don't say the water is bad, they just say it has the potential of being bad. You could boil your saved water to sanitize it but that would take extra energy and be contrary to what you are trying to do. If there was algae in this water it could possibly leave an off flavor anyway. We don't clorinate our water but water from the tap is safe to brew with until it is exposed to air or plumbing that is constantly exposed to air such as the aerator on a sink faucet. Once exposed it may not pass a coliform test. So if you are saving water that's been exposed to air, you are taking a chance. Maybe a closed reusable 2 vessel system would work best for you and eliminate the possibility of water causing the off flavor? You could leave a chlorine residual in this system to keep it from going bad.
And on another note 5.4 ph is pretty low for tap water. It is normally between 6 and 8.5 ph. May factor into the off flavor too.
 
I never even thought about that but yeah you basically have a pool of standing water, which is never a good thing.
 
Always interesting asking a question here.

I use caustic to clean (at 3%) and a no-rinse preoduct called Chemsan so don't think there's any bleach in that process.

I tasted the beer again today and it's definitely a tinny/medicinal flavour so very much still present. I do wonder if the hot weather has forced the water company to add extra chlorine but, equally, it could be me re-using water that isn't perfect as well. It is kept in a sanitised stainless vessel with a lid on but I have to accept that it's a factor.

I'm also wondering about the fermenters. These were both new and I did go through my caustic clean / rinse / sanitise process before using them I'm thinking now that my 3% caustic solution might want bumping to 6% or so.

I'm also going to delve into water chemistry. I think if I understand water better I might spot these things earlier.
 
I would say try a batch direct from the tap (with campden) for your next batch and see if it's still there. Remove the easiest and most obvious possible source of issue first.
 

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