To protein rest or not to protein rest?

[pennahighlandbrew]

That is the question. Pretty soon I'll be brewing up a kit from Northern Brewer (the Synchronocity Saison) which has five pounds of Weyermann pale wheat and three pounds of Pilsen malt for the bill.

I've only made a few all grain batches before, and I can't say I've ever used wheat. The recipe says I should do a protein rest (which I've never done). Can anyone tell me what the pros and cons of it would be? Is it really necessary/am I going to have poor head retention or a stuck sparge if I don't?

For further reference, my system is a ten gallon igloo cooler and I do single-step infusion mashes. I assume I could add half of my mash water around 122-131F and top off with hotter water to get to my rest temp?

Thanks in advance for the help!

 

[m00ps]

Ive never done a protein rest with wheat. Even for like wits and hefes that were 50% wheat or more. Normal mash temps works. Although I used wheat malt. Just make sure it isnt labeled "unmalted" or "raw" wheat

 

[Dryhops]

The "protein rest" is really about the breakdown of beta-glucans by the enzyme beta-glucanase, not much about protein. These are gums that are a source of stuck mashes and poor extraction. They greatly increase the viscosity of the wort and contribute to painfully slow run-off. Additionally beta-glucans contribute the the 'tieg' that forms on top of a grain bed that is impermeable to sparge water. While there might be some minor proteolysis, it's impact is negligible compared to what's already in the malt.

Are you fly sparging or batch sparging? If you're batch sparging then then you don't risk a stuck sparge since you're just going to beat the hell out of the grainbed anyways. Fly sparging would benefit from a protein rest.

How much wheat is in the grain bill? More than 20-25% and you'll start to notice and difference in run-off.

So your pros of doing the rest are simply a more fluid run-off and potentially better extraction. Your cons are having to deal with balancing your mash water additions to raise the temperature from the protein rest to the saccharification rest.

I would not simply add half of my mash water. Make sure you add enough water to fully hydrate the malt, but mash thick. 1:2.5 perhaps. Then I would add smaller amounts of hotter water to raise the temperature to saccharification.

Lastly, in regards to your poor head retention question, excessively long protein rests can be detrimental to the head of a beer. In this case, the extended rest time allows for substantial proteolysis that is foam negative. Conversely, a brief rest can be beneficial to foam stability. This all has to do with the degree of protein breakdown.

 

[Ninoid]

I wonder if protein rest can reduce the amount of proteins in the wort and increase clarity of beer?

 

[dmtaylor]

If you want a thin, watery, crystal clear beer with poor head retention, then by all means, do the protein rest.

Personally I wouldn't.

 

[bleme]

I've only done a protein rest once, and I think that was probably on a NB kit also. The instructions say that the protein rest is optional but that mash is 62.5% wheat. I'm leaning toward doing the rest.

 

[leonardoreges]

Protein rest is just needed for grain bills with 25% plus of unmalted grains. Wheat may be malted or unmalted, have to see what kind are you using. In other cases, as said above, it yields thin, watery beer with poor head retention.
It does not reduces the amount of proteins, it breaks then into smaller chains.
Do it or not according to your grain bill.

 

[Ninoid]

As the proteins are broken into smaller chains, the yeast will turn them into alcohol and will not affect the clarity of beer to the fullest extent. The head can be filled with steped crystal malt. That's my thinking.

 

[wilserbrewer]

My basic understanding is that the protein rest was developed to make sticky mashes more suitable to commercial brewing systems, in a home brew set up, not so sure of the benefits.

 

[booth74]

It can also help fermentation as it extracts amino acids to keep the yeast happy

 

[Ninoid]

It can also help fermentation as it extracts amino acids to keep the yeast happy

Some acidulated malt can this.