Aluminium kettle question.

[Lyikos]

I brewed my first batch in an aluminium kettle without first reading you have to boil water in it first. That batch got too many tannins and was meant to be expermental for the purpose of testing new eqipment and the tannins ended up coving up the metalic taste pretty well (lol). Since then I have boiled water in the kettle for an hour and got the needed brown oxide layer. However I'm still getting off tastes from the kettle, I boiled some water and tasted it alongside water that was unboiled and boiled in a small ss pan. The aluminium kettle still contributing mild off flavors.

Should I be worried? When I boiled wort no oxide layer formed so I'm guessing the chemistry of wort protects it, but would like to know for sure before making a serious batch.

 

[broadbill]

I brewed my first batch in an aluminium kettle without first reading you have to boil water in it first. That batch got too many tannins and was meant to be expermental for the purpose of testing new eqipment and the tannins ended up coving up the metalic taste pretty well (lol).

maybe the flavor wasn't there in the first place?

Since then I have boiled water in the kettle for an hour and got the needed brown oxide layer. However I'm still getting off tastes from the kettle, I boiled some water and tasted it alongside water that was unboiled and boiled in a small ss pan. The aluminium kettle still contributing mild off flavors.

Try this: take the sample in identical glass jars, and have somebody mix them up for you. See you if can taste the differenct then.

 

[Bensiff]

I'd agree with broadbill on doing a blind tasting. I didn't season my aluminum kettle and it never had a bad taste. Sometimes you can get a metallic taste from yeast which goes away after it settles to the bottom. BTW, I don't have a visible oxide layer either, shiny aluminum. As well, I'd look for other sources of tannins...pH being your usual suspect.

 

[Lyikos]

I might try that, but its pretty obvious imo.

 

[Bensiff]

It may be so...I can't stand corn from a can, I can taste the metal. My dad used to try and trick me growing up, but I always knew.

 

[broadbill]

I'd also be interested to hear in how you had tannin extraction. Short of boiling your grains, I be surprised if you really did it.

 

[Lyikos]

I'd also be interested to hear in how you had tannin extraction. Short of boiling your grains, I be surprised if you really did it.

180 degree sparge. It leaves a ligering bitterness on my tounge for hours. I searched hbt threads and found that was the most likely explanation, followed by cohumolone from a bad batch of cascade. But still my recents tests are done with pure water. The water sample boiled breifly in an unconditioned kettle was the worst, so there is quite a bit of improvement nontheless.

 

[Bensiff]

Yup, after pH issues over temp would be the next big bad for tannins...I think you can toss that issue off your list of concerns.

 

[BetterSense]

i never conditioned my aluminium turkey fryer and the first batch I made in it tastes fine after months of aging.

Also, my kettle does not have a layer of brown oxide; just regular silver-looking aluminum.

 

[Lyikos]

Fairly certain I found the culprit. Tap water pH is way to high, and I had a bad batch of pH strips that failed to tell me this sooner. I dug up old aquarium pH measuring solution and found it takes quite a few drops of vinegar to titrate down to neutral.

This pretty much means that whenever I boil unmodified water the rate of reaction accelerates and tiny chunks of aluminium oxide fall off the wall of the kettle and end up being in the glass once it cools (oxyclean threads told me aluminium and aluminium oxide react with bases). I'll be fine when boiling acidic wort.