Gladfield Ale Malt Clarity

[Matt Smith]

I brewed a blonde ale today with Gladfield Ale Malt. It was my first time using this, so I went with 100% for the grain bill to familiarize myself with its performance and character etc for future brews.

One thing I noticed was that my wort going into the fermenter was cloudy. I use whirlfoc for kettle finings (1.2grams for a 20 litre batch) and have always had crystal clear wort going into the fermenter when using Golden Promise, Maris Otter, Kolsch and all of the Weyermann base malts. I know Gladfield apparently has a high protein content...I'm wondering if this is the issue, or if it is a ph/conversion issue (although I did get 85% efficiency).

Just wondering if anybody has had similar experiences and how they fixed it. Should I simply increase my whirlfloc dosage ?

[Dougal]

Dougal, when you're measuring mash pH (of say a 5kg mostly Ale malt NZPA grist) what values do you usually get back for Gladfields?  How do these compare with other malts? (Bairds or Malteurop)

I'd have to look at my notes, but for a grist like that from memory, 3-4g of gypsum or CaCl2 in the mash. The pH would be around  5.8-6, so I'd then correct with about 5-10ml lactic acid. (Don't take the acid recommendations as gospel though: my lactic is a 10% solution of whatever the commercially available lactic is, and I don't know the strength of that.)

Can't really compare it with other malts as I use Gladfield pretty exclusively, but those times I've used other base malts the pH has fallen in the normal range without needing much adjustment if any.

[Tilt]

Thats really useful info Ralph and Dougal, thanks. 

As "regular" Gladfields users have you noticed much variability between malting batches?  There are some historical posts somewhere (I think from as far back as 2009)  that talk about having to adjust mash parameters depending on which batch you're using. 

Oh yeah - and with the salt and acid adjustments you mention above are you getting clear run off?

 

[Dougal]

Nah, it's been pretty consistent in the time I've used it, especially if you start with one of their malt spec sheets for your ingredient profile.

Provided I'm not using wheat I get pretty clear mash runoff. 

[Ralph]

I have not really noticed variability between their batches. I have used both their ale and pilsner malts and both have gone fine. I find the malt works fine, and the beers that won me the Champion Home Brewer in last years national home brew comp were made from Gladfield base.

Clarity from my batch sparging seems fine.

[Dougal]

Just in case anyone's interested. Here are some Gladfield spec sheets from about 6 months ago.

https://www.dropbox.com/sh/xgcwlknwd2qhmbc/r4qKDljLOF

[Tilt]

Glad to hear they're consistent nowadays.  News re Gladfields is they'll be producing some specialties towards the end of the year with a new roaster on board pretty soon apparently.

I brewed a NZPA with 5kg of Gladfields Ale malt tonight.  Specialities were Caramalt, Carapils, light crystal and Caraamber about 12% of the grist total.  Keeping in mind the comments about clarity I paid attention to the pH.  Brewing with Onehunga water (Alkalinity CaCO3 57.8 ppm using the EZ Water Calculator here).  I  added 8g Gypsum, 2g CaCl and 2g Epsom salts.  According to the spreadsheet the theroretical mash pH should have been 5.38.  My measurments using pH strips (with poor precision as they cover the range 1-11) showed a level somewhere between 5.5 and 6.0.

The mash run off after 8L of vorlauf was clear and the wort into the kettle after 0.5tsp Koppafloc in the boil at 10min was also clear.  I used 2tsp of kitchen grade citric acid in 30L of sparge water to keep the sparge in the right range too.

Admittedly all these additions and measurements are approximate given the limits of my equipment - but the end result seems to be clear wort into the ferment.  Here's hoping the results are reproducable as I'm planning a dry stout with the same malt on Sunday....

[Ralph]

I would think the finer crush was the culprit. If you crush too fine you will tear up the grain husks and also get a lot more flour. Having the husks torn up too much will mean they will not form as good a filter bed and having more flour makes it even harder to get the mash to run clear.

The better efficiency is likely to be because of the finer crush as well.

[Dougal]

Gladfield does have a higher pH than most base malts, so especially with a 100% base malt grist and a single infusion mash you'll get protein haze because your mash pH is too high.

There are three solutions to lower the pH into the right range.

1. Use some darker grains. Their acidity will bring the pH down, and in practice with Christchurch water which is about pH 7.8, any beer that's amber or darker with Gladfield base malt will be crystal clear.

2. Correct the pH with salts using a residual alkalinity spreadsheet like John Palmer's. Gypsum or calcium chloride will both lower mash pH. 

3. Correct the pH using acid, or acid malt.

I reckon it's most likely to be pH, but as Richard says, vorlaufing is a must if your crush is fine.

   

[Matt Smith]

Thanks Dougal. I did use a little gypsum and calcium choride, based on the EZ water calculator that's floating around on the internet. It had my estimated PH at 5.48, so I'll aim for a little lower next time. I'm not sure how accurate the calculator is, Id be interested to compare when I finally get a ph meter.

[Raffe]

For what it's worth, I used 4kg of Gladfields (also crushed using Richard's mill) at the weekend in a pale ale. I had a little munich and caramunich in the bill also, plus some gypsum, calcium chloride & epsom salt. I fly sparge, and got clear wort runoff after about 5L of recirculation.

Stupidly I forgot irish moss in the boil, only realising when siphoning into the fermenter after the whilrpool & chill and the wort was cloudy....

[Matt Smith]

Ah nuts, I did that a few brews ago too, super annoying after so much attention to detail with the vorlof and ph etc

[JR]

Not quite the same issue, but does anyone else get excessive amounts of, I assume protein, left in the kettle after using gladfields malt. I done a 65L batch.  After chilling and settling for an hour or so the first 40L came off really clear but from then on it was thick lumpy brains about 30mm diameter. I was hoping to get another 15L of clear wort.  Is this abnormal?  I dont seem to get anywhere near as much of it from GP MO or Wyermans Pils malt.

Does it mean I need a more through mashing reigeme with a protien rest or something? 

I used ph5.2 for the mash and sparge water

it was 100% gladfields malt

I used 1.5tsp of koppaflock @ 10min

I mashed at 65degrees for 90mins