I am new to the forum and very glad that it exists. Its nice to have an outlet to bounce ideas and opinions off of with like-minded, enthusiastic people in the distilling world. Let's talk rye!
We are getting ready to run a few rye mashes and i'm looking to tighten up the recipe and mashing schedule - rye can be a tough grain to mash and i'd like to minimize the headaches. We have an old school mash tub (250 gal) with an agitator but no grist hydrator and are planning to use 100% rye (raw and malted) without liquid enzymes. The questions I have are:
Does doughing in at cooler temps (86-95F) reduce the formation of dough balls?
How important is a beta-glucan/protein (95-122F) rest to reduce mash gumminess? Can it be skipped with the addition of premalt?
Is a sterilization rest (176-186F) required to kill any bacteria in the grain?
Is 18% (85 lbs.) malted rye enough to convert 374 pounds of raw rye flour?
Any insights, experiences and horror stories dealing with rye are greatly appreciated. Thank you.
Hi Erik. No one appears to want to have a crack at answering your enquires. You may have asked too many questions in one post!
To get the ball rolling I will give you my 2 cents worth then hopefully others will make improvements.
I make 100% rye but I malt my own and use it green at about 25%
18% malted rye should be sufficient. I have heard of large distilleries using 10% barley malt. I beleive rye malt has more DP than barley so 18% should cover it easily.
I have never tried starting at low temperature to reduce balling but I would be fairly certain you would be correct. In my experience add the rye very quickly to reduce balling. If it is added slowly the flour/grist soaks up the water so when the last of the flour is added the water has become a paste and cannot soak into the last addition. I don't know exactly how your agitator works. I found my agitator needs some assistance with breaking up larger balls. I used to use a small garden fork as if it was a kitchen whisk. I have now made very industrial whisk that works a treat breaking up the larger balls that are floating near the surface
The coarser the rye flour/grist the less balling.
I once tried a stepped mash with a protein rest and I did not see any reduction in viscosity. But I am not saying it won't work for you.
I can't heat my mash tun easily so I start with a strike temp of around 90c (194 F) and drop from there. Starting high will kill most nasties in my grain if there are any.
Many people say beta glucans cause the gumminess in rye but I am not so sure. I read somewhere that arabinoxylans are the culprit. Xylanase should help if you can bring yourself to use some.
18% is not enough to convert all the rest of it.
18 percent is more than plenty. 5 percent is enough. Unless you are taking the mash temp up after mashing and killing the enzymes so you get no secondary conversion in the fermenter.
You need to find out the diastatic power, then make sure the diastatic power is high enough to convert the whole grain bill, so if you were to use all malt, then you're going to see if your total malt bill's diastatic power is high enough to convert the starches into smaller peices. If you are malting corn for example, it doesn't have enough to convert itself. I find that strange but its true.
So, if you're using unmalted grains, then you would see if the portion of malted grains have a high enough diastic power to convert the entire grain load. Sometimes rye, wheat, and barley have high values and are used malted to convert other grains. Wheat has a diastatic power of 130-160, it needs much less to convert, so it leaves extra... super bonus for raw wheat. Not sure about rye, plenty of diastic power grain charts. That's the reason for grains with corn.
As to the question on the high temp, that is to stop conversion. To kill enzyme activity, in beer there is a reason, in distillate I'm thinking it won't matter.
Lastly, the rye is like wheat, both have beta glucans in high amounts and need to have the rest or you'll have problems getting it to be less sticky and will be a problem to move in the mash kettle, it literally could potentially turn to concrete, its the damnedest thing, there are kind of cool videos of people doing backyard batches and it spinning around then getting harder and harder until the mixer sticks. Then some enzymes are inserted into the tank and slowly it starts to release. However you are going to have trouble getting good yeilds without getting the enzymes free to break down the betaglucans.
I've also heard that you should add vegetable oil on the fermenter to stop the rye monster. It grows like a mother fucker and explodes out of the fermenters. Dave Pickerall told a funny story at Seibel of a batch he first made at the George Washington Distillery and it basically was on the floor the next morning. He researched some old manuscripts on the old methods, which they used lard, breaking the surface tension I think allowing it to stay put and bubble away. Otherwise he found a mess poured out and hardened and it was a major bummer. Especially if you meet the guy, he's a large guy capable of working the shit out of some big mashes, so if you hand paddled the mash and it fell on the floor OUT of the fermenter, that would suck... I'm not sure I'm into hand working a batch even for historical fun, my props to him and his back. I'm a bit short, taller guys have tall people skills, I have pluggin in the electrical plug on the floor under the fermenter skills or climbing up places skills, haha.
Lastly, the rye is like wheat, both have beta glucans in high amounts and need to have the rest or you'll have problems getting it to be less sticky
15-30 minutes. i'll look in my books in a little while but i usually hold for 30 minutes at 129 farenheit.