Protein rest?

[_Mick_]

Hey guys, just wondering if I could get some plane language info on the importance of protein rests during a mash. I'm relatively new to all grain and only done single temp infusion mashes.

Cheers
Mick.

 

[pyrosx]

I'd read this section:
http://braukaiser.com/wiki/index.php?title=The_Theory_of_Mashing#Protein_converting_enzymes

Then probably read the rest of the site as well

 

[RelaxedBrewer]

With modern malt you do not really need to worry about a protein rest. However if you are using non malted ingredients such as raw or flaked grains it could be beneficial.

A protein rest can be done to break down proteins that may be present in wort. There are two temperature ranges that are most effective for breaking these proteins down and effect different types of proteins.

There are two different types of proteins that we brewers care about. The first type causes haze in the beer (chill haze) and the second helps with head retention/body.

The range 45-53C is the temperature that breaks down the haze creating proteins. A rest in this range is used to clear the beer.
The temperature range 56-58C breaks down the head retention/body proteins. A rest in this range is used to thin out a beer.

The use of these rests is dependent on your ingredients and what type of beer you want to make.

RB

 

[QldKev]

You will see a lot of text book reasons why with modern malts you don't need too, and a lot of people who have never tried them telling you not to do it.

All my beers get a 55c /. 5min step. Try it for yourself and see what it does for your beer.

 

[_Mick_]

Interesting stuff, my next brew will be a dry lager using just pils malt and rice so a good rest at the 45-53c range would be beneficial to clear up the end product?

 

[RelaxedBrewer]

You will see a lot of text book reasons why with modern malts you don't need too, and a lot of people who have never tried them telling you not to do it.

All my beers get a 55c /. 5min step. Try it for yourself and see what it does for your beer.

I am very interested in this. What do you gain from doing this?

You are basically doing a short protein rest in the region that is supposed to thin the beer out.
Are you trying to thin it a bit or are you getting some other effect?

 

[RelaxedBrewer]

Interesting stuff, my next brew will be a dry lager using just pils malt and rice so a good rest at the 45-53c range would be beneficial to clear up the end product?

Theoretically yes. I have never used rice before, so I am not sure how much haze it might cause but it definitely would not hurt.

 

[manticle]

I do similarly to Kev. In conjunction with a 10 minute rest at 72, I notice a lovely, creamy looking head that laces and retains.

 

[verysupple]

I do similarly to Kev. In conjunction with a 10 minute rest at 72, I notice a lovely, creamy looking head that laces and retains.

Have you ever tried just the step at 72 without the low temp rest? I ask because I noticed mine have better head formation and retention just with the high step (usually 65 - 68 and then up to 71) and wonder if it could be even better with the low step as well.

 

[manticle]

I have and it works well but I prefer the results with the two.

Never done side by side though so just relying on fairly inaccurate 'notions and memories"

 

[QldKev]

I wasn't going to give it away that easy and make you test it for yourself, but manticle has said it 100%. As manticle also said combine it with a 72c step. Only difference I do either a 15min or 25min rest at 72c as I like my beer a bit fuller. (also most my beers are 3.5 to 4% abv)

If you wonder if it would be better with the low step aswell, try it, you have nothing to loose.

 

[wbosher]

So you would do something like 10 mins at 55, 60 at 65 to 70ish, and then 10 at 72? Do you still do the mashout at 78? I do BIAB with gas so this may not be too easy to do, but still interesting

 

[mje1980]

I do the 72-15mins as its a bit of a pain to do 55,65,72, but I have done it and noticed good results. All my beers now get the 72 rest for 15 mins, even the super dry ones like Belgians.I have manticle to thank for putting me onto that. I find that just the 72 gives good lacing. It's also much easier to do, than the extra step if you're limited by equipment.

If I had the blinged up beer maker that could ramp temp up easily I'd do both.

 

[RelaxedBrewer]

oops, I got my rests round the wrong way.

It should be

The range 45-53C is the temperature that breaks down the head retention/body proteins. A rest in this range is used to thin out a beer.
The temperature range 56-58C breaks down the haze creating proteins. A rest in this range is used to clear the beer.

This would make sense with what manticle and QldKev were saying.

 

[syl]

55 - 15
65 - 45
72 - 15
75 - 10

 

[Bribie G]

I've read (Palmer maybe) that protein rests actually chop some proteins into smaller chains that promote heading and lacings. It's not about whether you want to degrade proteins in general, more a case of which proteins you want in your finished beer.

 

[Black n Tan]

what happens at 72C?

 

[Bribie G]

Any remaining starches are converted by Alpha Amylase, in case they got missed at lower temperatures, generally to unfermentables such as dextrins that give body. Doesn't take Alpha Amylase long, mean bugger.

 

[manticle]

72 is high end alpha but also glycoprotein rest. It has been suggested that glycoproteins contribute to head formation and retention.

 

[mje1980]

Bit of a bump but I now take the extra 10 minutes to add the 55-58c rest as well as the 72 for pretty much all my beers. Except uk ales, and pale ales, they get the 72 but not 55. Not really that much more effort. 2 pots on the stove instead of one.