Purple hot break

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GalBrew

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Ok, this is a new one for me after a decade of brewing so I thought I’d put it out to the brains trust for opinions.
I’m brewing a fairly simple Kolsch style beer and as it has reached the boil the hot break has formed on top (normal I hear you say). The odd thing is that it is a distinct tinge of purple rather than brown. A full layer of purple break material formed and as soon as the boil started to roll it broke up and the break material underneath was white.
Has anyone seen this happen before? 🤷‍♂️

The pic below is showing the break as the boil starts to roll.

185D90E0-F851-4701-8185-E346D441400E.jpeg
 
What was the grain bill? Any malts different to your usual? (different maltster, etc)

The grain bill was as follows:
Gladfield Light Lager
Weyermann Munich I
Best Acidulated
Rice Hulls

All I’ve used before and never seen any purple??
 
Can't see it coming off the grain, is the rice hulls a recent batch? Put some in a saucepan and boil them up could be coming from a chemical they sprayed the rice with.
 
Can't see it coming off the grain, is the rice hulls a recent batch? Put some in a saucepan and boil them up could be coming from a chemical they sprayed the rice with.
The rice hulls are quite old (a bag lasts a long time apparently). I suspected the hulls, but I used them a month ago and no purple. It’s really weird, I’ll give that a go though.
 
Taking a bit of a stab in the dark but I would look into anthocyanins from hops. Anthocyanins are a family of flavonoids common in many plants, can be red, purple, blue even black, probably the most common (extreme) example is beetroot.
Chemically related to other polyphenols the colour is very dependent on pH. This pick is from Wikipedia shows the effect of pH on Red Cabbage extract.
1600378533596.png

Would be interesting to know your wort pH, If you are getting Purple I think you might be a bit outside the ideal range.
Mark
 
Taking a bit of a stab in the dark but I would look into anthocyanins from hops. Anthocyanins are a family of flavonoids common in many plants, can be red, purple, blue even black, probably the most common (extreme) example is beetroot.
Chemically related to other polyphenols the colour is very dependent on pH. This pick is from Wikipedia shows the effect of pH on Red Cabbage extract.
View attachment 119130
Would be interesting to know your wort pH, If you are getting Purple I think you might be a bit outside the ideal range.
Mark
The purple hot break was all before I added any hops as I only did late additions with this beer. Unfortunately I didn’t take a pH reading. You can see on the pics below the post boil trub looks normal, but you can see the purplish break ring just under the 30L mark on the Grainfather.
A1DFC999-ADF3-4C08-A275-DD04C607FA9D.jpeg
933D4B32-4059-4D11-B649-0737C8219C7C.jpeg
 
Well that's me out of guesses.
Next thought would be some sort of contamination, followed by an act of God.
Maybe take a handful of the rice hulls, steep them in hot water, strain to get a clear "tea", add some acid to one portion and some base to another and see if there is any change in colour.
But if the wort tastes OK odds on it wont matter - odd though.
Mark
 
If you don't report back in 3 weeks we will assume it wasn't good to drink
 
When they spray some cereal crops they sometimes add a dye just to make sure they have sprayed where they should have, could be in the herbicide or pesticide and adsorbed by the plant. I would seriously check out the rice hulls. And Jimi Hendrix, forget Prince.
 
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Legit question, is there an alternative to rice hulls? Not keen in pesticides etc in my beer
 
Unless you are getting "Organic" malt its pretty much same same!
Both crops are sprayed with all sorts of things, stored grain and malt is also treated at need to control pests.

As for an alternative, with good milling practice I have never had a problem with up to 60% Wheat, will lauter just fine.
Oat hulls are available from some malt suppliers (occasionally) but then you have the same issues as with any other grain or grain product.
Mark
 
When they spray some cereal crops they sometimes add a dye just to make sure they have sprayed where they should have, could be in the herbicide or pesticide and adsorbed by the plant. I would seriously check out the rice hulls. And Jimi Hendrix, forget Prince.

Broad acre crops like cereals are never sprayed with a dye. It is commonly used when spot spraying to mark individual plants that have been sprayed. Think a patch of blackberries or briars or the like.
In broad acre situations either a foam marker is used, where a blob of foam is dropped from the end of the boomspray, or more commonly these days gps is used for guidance or to actually steer the spray rig.
 
Broad acre crops like cereals are never sprayed with a dye. It is commonly used when spot spraying to mark individual plants that have been sprayed. Think a patch of blackberries or briars or the like.
In broad acre situations either a foam marker is used, where a blob of foam is dropped from the end of the boomspray, or more commonly these days gps is used for guidance or to actually steer the spray rig.
They use red dye on rice crops as a tracer.

While all cereal crops are sprayed, it is the hulls/husks which carry the bulk of the contamination rice hulls aren't washed unless for fodder, some countries don't even allow it for chicken litter unless it is washed.
Our malted grain is washed during the steeping process, I think if someone wanted to use rice hulls in the mash tun to just give them a rinse in a colander.
 
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