Ferulic acid rest disaster

[darlacat]

Brewing a saison today, and had an absolute disaster using a ferulic acid rest. Have done this step before with no problems in wheat beers. However, today it caused the wort to gelatinise, forming milky clumps, and burned onto the element, causing the mash tun to trip out. I emptied and cleaned out the mash tun, filtered out the gelatinised clumps, and put everything back in - but as soon as the element touched the wort, it scorched again!

I was following the mash schedule from the Farmhouse Ales book:
- 30 min rest at 45c
- 15 min rest at 55c (didn't make it this far)
- 30min rest at 62c
- 15min rest at 68c

Grain was extra pale with small amounts of bohemian pilsner, torrified wheat and carapils (<5% each for the last two).

What went on here?

Is the grain from this batch salvageable, or shall I just dump it and start again...?

 

[thegrantickle]

DUmp it and start again. There's no going back from scorched wort.

 

[darlacat]

DUmp it and start again. There's no going back from scorched wort.

Yeah, the wort has to go...just wondering if the grain itself was salvageable, starting again with a single infusion mash and fresh water. Although I will likely dump it in any case now as it's too late in the day to start again...

Got a starter of saison yeast on the go, so will try again on Sunday...with a single infusion mash!

Any idea what caused the wort to gelatinise? Have done ferulic rests with wheat beers in the past - including a wit with 50% unmalted wheat - and had no issues.

 

[thegrantickle]

I would dump it to be honest. Could be too finely ground? That's my initial thoughts

 

[GeorgieV]

Are you controlling the power at the heating elements? For example, I use a 3 kW tea urn for mash tun and if I try to heat up the mash on full power it will be scorched. So, I ended up using a PWM power regulator and kerb the power to 15- 20 % for a slower heat up.

Another factor is the fine flour in the grain - the more of it, the more likely to have burnt residue on the element.

 

[darlacat]

Are you controlling the power at the heating elements? For example, I use a 3 kW tea urn for mash tun and if I try to heat up the mash on full power it will be scorched. So, I ended up using a PWM power regulator and kerb the power to 15- 20 % for a slower heat up.

Another factor is the fine flour in the grain - the more of it, the more likely to have burnt residue on the element.

Yeah, controlling the power. Have never had this issue before regardless of mash temperature. The problem this time was that the wort was gelatinising - forming thick, cheese-like curds that were dropping to the element. There was about an inch of the stuff coagulating above the element.

 

[darlacat]

I would dump it to be honest. Could be too finely ground? That's my initial thoughts

No, the crush is fine - have done other brews with the same batches of grain. Plus I use a grain bag to hold the grain.

Problem this time was gelatonisation of the wort. What caused the gelatinisation? Too long a ferulic acid rest?

 

[darlacat]

Also the whole wort was incredibly white and milky...

 

[Sadfield]

I would dump it to be honest. Could be too finely ground? That's my initial thoughts

I think this is it. I would have thought there was too little wheat in the grist to be a problem even though it can gelatinise at 52c. It does vary though, so perhaps a different batch of wheat gelatinised at a higher temperature than what you have now.

The ferulic acid rest should be done 40-50c, not sure what benefit the 55c step would be in this context given <5% Wheat. Probably best to skip and go straight to 64c.

Here's a handy table though.

 

[darlacat]

I think this is it. I would have thought there was too little wheat in the grist to be a problem even though it can gelatinise at 52c. It does vary though, so perhaps a different batch of wheat gelatinised at a higher temperature than what you have now.

The ferulic acid rest should be done 40-50c, not sure what benefit the 55c step would be in this context given <5% Wheat. Probably best to skip and go straight to 64c.

Here's a handy table though.

Thanks! Really helpful. I think I'll be skipping the ferulic acid rest next time...Will attempt this beer again on Sunday, as I have a starter of Wyeast 3724 on the go - will just be doing a hochkurz mash of 30mins each at 62 and 67!

I've posted this on Home Brew Talk also, and received some useful responses there. Suggestion that the issue is that it did not gelatinise, and that gelatinisation temperatures can vary from batch to batch even with the same malt and maltster.

Chalking it up to experience, and will be avoiding ferulic acid rests from now on!