Experiment Time

[SJW]

Alpha Amylase Effects on Wort Fermentability over Time.

A similar experiment was documented on the braukaiser.com web site some time ago with somewhat inconclusive results.

Aim: To find out if alpha amylase activity alone increases wort fermentability after full conversion in a mash where beta amylase was not activated.

Method: The plan is to mash 5kgs of pale IMC malt continuously for 3 hours at 73 deg C and draw off 1 litre samples at 30min, 1 Hr, 1.5 Hrs, 2 Hrs and 3 hrs. Using the Braumeister it will be a simple task to heat strike water to about 76 deg C and hold at 73 deg C for the allotted times.
Then boil each sample for 10 mins in an Erlenmeyer flask, cool in an ice bath and transfer to a P.E.T. bottle for fermentation. I plan on getting the 1 litre samples drawn, boiled and cooled in between collecting each sample.
Then I will pitch 3 grams of US-O5 in each sample.
The results will include O.G, F.G. and apparent attenuation.

My Theory: I am assuming that by using a modern well modified malt a protein rest would no be required, to emphasise shorter chained protein or amino acids, even though I am not planning on activating Beta Amylase or Limit dextrinase at all.
My thinking is that Alpha Amylase working randomly on glucose molecules should create some maltose by splitting glucose chains thus converting all the Amylose.

Question 1: While Beta Amylase splits 2 glucose molecules at the non reducing end of a glucose chain, would the above mentioned random activity of Alpha Amylase by chance do the same job? GIVEN ENOUGH TIME? Thus converting some if not all Amylose. This should create enough maltose for the yeast to do its job and make some alcohol in the wort.
And the question I am trying to find the answer to is, given enough time would Alpha Amylase convert enough starch to produce a fermentable beer?
Amylopectin will be delt with by the Alpha Amylase and given enough time this experiment should find out if extended Alpha Amylase activity on the Amylopectin will produce a suitably fermentable wort. Ie, some maltose.

Any thoughts on this would be appreciated. The other way I could go would be to dough in well below gelatinisation temps and raise the temp 1 deg C per min. (in the Braumeister) and going straight to 73 Deg C, this would give Beta Amylase about 5 or 6 minutes to create some maltose.
Thoughts.

 

[QldKev]

It would be a good experiment to test some of the theories in place.

I would go straight for a 73c mash rather than ramping the temp to it. It is an experiment and not trying to create a rounded beer, so the ramping from a lower temp will just add more confusion into the final product, giving it some thin/dryness.

Please record the SG and FG of each batch.

Also if you could do one extra step. After the three hour mash, do another 1hr step at 62c. The theory says the enzymes can survive 80c temps if in the dry malt, but get denatured and will not reactivate in a wet mash. So based on the theory the beer from the 62c step should be no real different from the 3hr.

My guess on the outcomes it all the beers will be similar. 30mins at 73c should see most the conversion completed, with only a minor improvement in efficiency after that point.


QldKev

 

[Thirsty Boy]

of course it will

and how are you going to manage to not activate your beta amylase? I think you'll find that its very active indeed at 73

 

[Nick JD]

The mash will be finished in about ten minutes at 73C.

 

[Helles]

What about the water/grain ratio
Your removing 5 lts of wort
Youll end up with thick mash
How will this effect it ??

 

[manticle]

of course it will

and how are you going to manage to not activate your beta amylase? I think you'll find that its very active indeed at 73

Kind of my thinking. How do you know that only alpha is doing the job when the various enzymes are all active at various temps (just that some temp ranges favour activity of one over the other)? Beta will still be activated at 73, just as alpha will be activated at 62.

The only way to do it would be to isolate the enzyme and observe how it worked with isolated starch chains (I think - my experimental design was just thought of on the spot, right then).

Not an uninteresting concept- to see (not if but.... ) how quickly and efficiently but the experimental desing needs some tweaking I think.

If you do do it just for fun, definitely don't ramp as you'll be giving a range of enzymes their day in the sun. Pick the rest and target it bang on.

Might be interesting as a comparison between 62 rest for 10 and 73 rest for 90 with the same malt rather than trying to specifically pit beta against alpha.

 

[Nick JD]

Use unmalted barley and add the specific enzyme.

Otherwise, consult the 100 years of research already done to find the answer. Brewing is not a 16 year old virgin, it's a 95 year old retired wharfside hooker.

 

[SJW]

Also if you could do one extra step. After the three hour mash, do another 1hr step at 62c. The theory says the enzymes can survive 80c temps if in the dry malt, but get denatured and will not reactivate in a wet mash. So based on the theory the beer from the 62c step should be no real different from the 3hr.

Great idea Kev, I will do just that.

As for the Beta Amylase still being active at 73 deg C, I guess we will never know. Info taken from Brewing Science and braukaiser.com state,

The optimal pH range for beta amylase between 5.4 and 5.6 and the optimal temperature range is between 140F (60C) and 150F (65C). Above 160F (70C) beta amylase is quickly deactivated [Narziss, 2005].

I think it just me but I always ask WHY. I have always brewed following these principles that work and we all know. Single infusion mash at 67 deg C, cooler for higher attenuation and warmer for more body. Or the step mashing way with 60 deg C & 70 deg C for varying times.
While in the US recently I was talking with a group of commercial brewers from Oregon who said they do a slow ramp up from 50 deg C to 70 deg C and hold it there for 1 hour then mash out. I only assumed they made good beer this way but I never got time to question him on this method. That’s when this experiment was born.

Steve

 

[Thirsty Boy]

optimal, range, quickly - all very important words from the quote you provide.

experiment away, thats always a good thing - just be aware that the words you used to describe your experiment, about "not activating beta amylase" suggest some underlying assumptions that aren't what's going to actually happen and the results will be influenced by more things than the simple model that would exist if it was.

 

[Mike L'Itorus]

Ask Raven what a beer that has been brewed using a jumpmash technique tastes like....he has experienced it within the last 6 months

 

[QldKev]

[quote name='Mike L'Itorus' post='945635' date='Aug 19 2012, 06:25 AM']Ask Raven what a beer that has been brewed using a jumpmash technique tastes like....he has experienced it within the last 6 months [/quote]


Haven't heard about the jumpmash for a few years. From memory the main difference between that on this, is SJW was not going to mash in cold and ramp up so should not be activating the enzymes on the way through.

QldKev

 

[MHB]

Interesting experiment, but to quote TB Of course it will, the question becomes By How Much
When people add Dry Enzyme to beer they are adding an exogenous Alpha Amylase (amylase but not from the malt made by well trained bacteria) it proceeds to chop up more complex dextrins into simpler sugars many of which are fermentable.

In terms of conducting the experiment as SJW is brewing on a Braumeister it will be quite easy to preheat the water to 73-74oC, when mashing in at a LG of 5-6:1 there is going to be a barely 3oC drop in temperature if you wanted to you could preheat the malt (dry) to strike heat so there would be no temperature adjustment required.

I strongly suspect that there will be some Beta Amylase activity, albeit for a short time and during that time it will be pretty full on.
To give you an example the old way to make Invertase (before GM came along) was to dump a pile of live yeast into sugary water at 65-75oC, the yeast would be killed in a matter of seconds but in that time excreted a massive amount of Invertase, which could be harvested.
I suspect a somewhat similar response regarding Beta Amylase there will be lots of it early and it will be working hard, but that it will be denatured in a matter of minutes
Maybe taking a reference sample earlier (say 10-15 minutes) and testing it for fermentability will give you a base line for the contribution to the fermentability from Beta Amylase later changes to the fermentability could reasonably be ascribed to Alpha activity.

The question of samples affecting the experiment is fair, and always a bit of a bugbear in experiment design.
By the time the samples are taken most of the enzymes should be in solution, so each sample is taking enzymes out of the reaction but not taking any of the malt that the enzymes are to act on, effectively every sample reduces the amount of enzymes available to do the job.
The only way I can think of to minimise the effect is to take as small a sample as possible, you really just need enough to ferment and measure the change in S.G.
If you take a 100mL sample, cool it, split off 10mL (store in the fridge) and ferment the remaining 90mL, you could bring the unfermented and fermented samples and use my digital SG meter which only needs about 10 mL (Max dropped in a couple of hundred nice little 100mL amber lab bottles and caps a few weeks ago welcome to as many as you need)

Just a couple of other observations that might help with the experiment design
Alpha Amylase is degraded over time so the amount of activity will be falling as enzymes get fewer, optimising the pH (~5.7pH) and making sure you have plenty (like 250-500ppm) of Calcium will extend the life of the Alpha. The best pH for Alpha is pretty hard on Beta so should reduce the effect from the Beta Amylase.
I think taking a reference sample at 10-15 Minutes is going to be fairly important.
If you need any salts, acids, measuring equipment or the like happy to help, I like seeing brewers do well thought out experiments.
Mark

Nick you need to understand that there is a massive difference between saccrification (Insoluble starch being made soluble) and the end of mashing, that difference is exactly what this experiment is measuring!
It great to see you quoting from text books, better to see you referring other people to well understood brewing science and a dame shame you clearly dont understand what you are referencing.

 

[Nick JD]

Nick – you need to understand that there is a massive difference between saccrification (Insoluble starch being made soluble) and the end of mashing, that difference is exactly what this experiment is measuring!
It great to see you quoting from text books, better to see you referring other people to well understood brewing science – and a dame shame you clearly don’t understand what you are referencing.

Please refer to the table below as to my comment and the experiment's mash length.

 

[punkin]

I would be happy to supply a sample of Hightempase to the experiment. That way you could use un malted barley and throw it in at boiling, cook for a while and then cool at you leisure in the knowledge there is no gluco enzyme there but the alpha has been active. Enzyme works best at 98-105C
I also have some gluco if you wanted to experiment further.

Give me a pm and i'll send you a small bottle. i have half a litre or more in the fridge.

 

[MHB]

Seriously Nick, the table you have posted demonstrates the wrongness of your first post, the mashing wont be over in 10 minutes, for each temperature range in the table there is an increase in both extraction and fermentable extract. Actually its a pretty interesting table and suggests that the rate of increase in fermentability wont be all that high at 73oC, but in an experiment negative results are often just as useful as positive ones.
SJWs experiment (from my reading of his post) is trying to determine if the increased fermentability is down to the activity of Alpha Amylase.
WTF gelatinisation has to do with the subject at hand is beyond my comprehension ( yes I do understand the difference) just not how gelatinisation is relating to the activity of Alpha Amylase on starch at 73oC, that you would need to explain.
Mark

 

[Nick JD]

Actually its a pretty interesting table and suggests that the rate of increase in fermentability wont be all that high at 73oC, but in an experiment negative results are often just as useful as positive ones.

As the table clearly shows, mashing at 73C for 15 minutes or 90 minutes, the ratio of fermentable extract to non-fermentable extract is essentially (and within the limits of the OP's measuring capabilities) the same.

My first post that there will be largely no difference after ten minutes still stands and is a perfectly valid point with regard to the OP's hypothesis.

Time to let it go, Mark.

 

[SJW]

Of course some beta amylase will do some work, even at 72 or 73 deg C, but the aim of this test is not about gelatinisation or Limit dextrins or even beta amylase but the effects of alpha amylase on the fermentability of wort at extended mash times. I think I will go with smaller samples so as not to limit the enzyme activity in the remaining mash. As I mash at 5:1 in the BM, 5 samples of 100 or 200mls will make very little difference to the remaining mash.
Maybe this experiment may show that when using a Braumeister or RIMS system, that a slow increase in mash temp up to 70 deg C for an extended time will produce a good drinking beer.
As I have just emptied a keg I will order a brew now and mash it in at 20 deg C, and ramp it up to 70 deg C for 2 or 3 hours and see how that goes, prior to doing the experiment. Drinable beer comes before any experimental brews.