Polenta - Is It Ready Yet?

[jonocarroll]

It's been a while since I posted a brew-question. Feels good.

I brewed my first CAP on the weekend and it's now happily sitting in a NC-cube. As appropriate for the style, the recipe I was fiddling with called for a large portion of flaked maize, but the LHBS doesn't stock it, so I subbed some polenta, which I've never brewed with before.

Following the cereal mash procedure in Chapter 16 of How to Brew, I used my hooded BBQ as an oven and cooked up the polenta (along with a couple handfulls of grain), then dumped that into the mash. My pre-boil gravity was - as usual - spot on, but I am now wondering whether or not the gelatinization of the polenta would be evidenced by the correct SG... ? This leads me to several questions, an answer to any of which would be most appreciated:

- Is it possible that my efficiency was higher than expected and the polenta does nothing to the SG?
- Is it possible that the polenta would add to the SG regardless of gelatinization?
- Is there a way to tell if the polenta has been gelatinized at all?
- Will I be better able to tell once it's fermented by using a refractometer and figuring out the attenuation?

My mild ale will be brewed this weekend, and I'm also planning to use a bit of maize, but I'm wondering if it might be less stressful to track down some organic corn flakes or pop some corn.

Cheers in advance.

 

[Fourstar]

Polenta will gelatinise and convert in the mash so you will add some SG points to your OG as it is converted to maltose during conversion. Much like any other unmodified adjunct used in the mash.

I'd say the increase in gravity you see is due to conversion of the polenta adding a higher SG.

 

[Bribie G]

Why would you use a hooded BBQ to prepare polenta? All you need is a small stockpot and make up a thin porridge, cooks up in about 10 minutes and add to the mash at your mash temp. Fourstar adds his at strike temp, wouldn't make much difference one degree or another.

I've also been adding it just dry into the mash and it appears to be getting digested ok, however I haven't done any accurate grav. readings yet, I was more interested in seeing if it would give me a starch haze, which it hasn't. So my jury is still out on dry polenta. However cooking it up in a stockpot to gelatinise is dead easy, just one more pot and spoon to wash up. What I do notice is that when using either polenta or rice the wort turns out tasting nicely sweet as opposed to the often 'un sweet' taste of all malt wort, and this is an indication that the adjunct is being digested into fermentable sugars.

 

[jonocarroll]

Why would you use a hooded BBQ to prepare polenta?

How To Brew recommends heating to ~65*C, holding for a while, then heating to boiling before adding to the mash. In order to get even heating without scorching, a 150*C oven is recommended. Rather than warm up the house, I used my BBQ.

As for why all this is needed, well, that's part of my question I guess.

I've also been adding it just dry into the mash and it appears to be getting digested ok

Appears how?

What I do notice is that when using either polenta or rice the wort turns out tasting nicely sweet as opposed to the often 'un sweet' taste of all malt wort, and this is an indication that the adjunct is being digested into fermentable sugars.

Won't the amylase enzymes in your saliva convert the starches anyway? Isn't this why a chewed grain still tastes sweet? Is your wort perhaps just less malty, and therefore the sweetness is more pronounced?

 

[Bribie G]

How To Brew recommends heating to ~65*C, holding for a while, then heating to boiling before adding to the mash. In order to get even heating without scorching, a 150*C oven is recommended. Rather than warm up the house, I used my BBQ.

As for why all this is needed, well, that's part of my question I guess.

Pot works fine, just make porridge.


Appears how?

None left in the spent grain. Using rice I get 'rice ghosts' that collapse as soon as touched, obviously they have been hollowed out during the mash. Don't see anything left at all with Polenta

Won't the amylase enzymes in your saliva convert the starches anyway? Isn't this why a chewed grain still tastes sweet? Is your wort perhaps just less malty, and therefore the sweetness is more pronounced?

I don't chew it, I sip it. With Aussie lagers etc I use 4k of Galaxy and either 500 of Polenta or Rice in the mash and also a touch of sugar in the fermenter. Or alternatively I do just a 4k mash and add more sugars to the fermenter if I'm deliberately aiming for a Carlton style. I notice a big difference in the sweet taste of the wort between the two methods

 

[jonocarroll]

None left in the spent grain. Using rice I get 'rice ghosts' that collapse as soon as touched, obviously they have been hollowed out during the mash. Don't see anything left at all with Polenta

This isn't completely doubting you - I'm trying to learn. Wouldn't the rice starches also dissolve into the wort, leaving a hollow shell? Or are the starches just likely to be left in the husk? If I soaked rice for an hour in the absence of enzymes, wouldn't I make the same observation?

 

[Bribie G]

I see what you mean. No, the rice is added when cooked to a soft consistency, more mushy than for eating purposes. At that stage if you prodded one, it would just be a grain of rice, but in the spent grain (I BIAB and the grain is pretty well squeezed and quite dry) you can see what look like rice grains but when you prod them they are really just a very thin skin in the shape of a rice grain - there's no liquid in them, just the 'ghost' shape left over. I haven't used flaked maize but I would imagine you might see something similar. Actually next time I do a rice or polenta brew I'll see how good the old Kodak is and try to get a closeup shot. :icon_cheers:
When I get some more data and some photos together I might even start a brewing with adjuncts thread as lots of members post about adjuncts and we could maybe tie it together. For example I have started using semolina wherever wheat is called for - e.g. Coopers Sparkling clones, etc - and also getting good results, and I was round at a brewday where the bradsbrew used a heap of oats in a stout, I reckon an adjuncts discussion would be excellent.

Not to mention Troydo's potato beer he brought along to the BABBs meeting last Feb h34r:

 

[jonocarroll]

Bump. Just in case anyone else has some answers.

 

[Nick JD]

I'm scared of Rice Ghosts.

I wonder what the compound is that makes rice taste, well, ricey? It comes out in bucket loads when in the mash. I loves me some rice in beer.

Ricetose? You want Won Tons wi dat?

 

[mika]

As the others have mentioned, it will add to your OG. I guess if it didn't convert and you somehow achieve a much higher efficiency, from the other ingredients added, than you usually do, there would be no way of telling if it had actually converted.
Personally I wouldn't sweat it.

 

[Thirsty Boy]

If you hit your expected efficiency - the by far the most probable answer is that your polenta converted and everything happened as expected. Its not like using corn as an adjunct is a chancy affair... its one of the most commonly used adjuncts in brewing.

As people have pointed out - quite a few brewers here are using polenta without a cereal mash and its turned out OK (I personally wouldn't) so if you actualy did a cereal mash, then you are even less likely to have had an issue.

 

[jonocarroll]

If you hit your expected efficiency - the by far the most probable answer is that your polenta converted and everything happened as expected.

My question was just that - does the gravity imply that conversion occurred, or is it possible that the starches are making up some points?

A further question - if people are having no issues adding dry polenta to the mash, why is it recommended to use flaked maize at all?

 

[Thirsty Boy]

yes, it implies conversion occurred.

Dissolved starches might make up some points, but most unconverted/ungelatinised starch would simply stay in your mash tun or sink to the bottom or come out of solution in the boil - and if they dissolved and came through in your wort - then they almost certainly converted anyway, enzymes are very good and very fast at converting starch, the only reason they wouldn't is if it were ungelatinised, inaccessible or you r raised your mash temp so high you denatured the enzymes... but then you managed to access extra starch somehow (admittedly possible with corn as an adjunct.. if you hadn't performed a cereal mash)

Polenta is ungelatinised corn - I personally wouldn't put it in my mash tun. Just because the people who posted here haven't had problems, doesn't mean they can't occur. Its probably fine to use, but why settle for probably? ... if you use instant polenta (pre-cooked), it is fine to use. Thats what I usually use if I want to use corn. Or do the cereal mash.

Flaked maize is pre-gelatinised as part of the flaking process and can be added directly to your mash tun without worrying about whether you do or don't need a cereal mash. You don't.

 

[jonocarroll]

That's more along the lines of the answer I was looking for. A few follow ups though...

yes, it implies conversion occurred.

Dissolved starches might make up some points, but most unconverted/ungelatinised starch would simply stay in your mash tun or sink to the bottom or come out of solution in the boil - and if they dissolved and came through in your wort - then they almost certainly converted anyway, enzymes are very good and very fast at converting starch, the only reason they wouldn't is if it were ungelatinised, inaccessible or you r raised your mash temp so high you denatured the enzymes... but then you managed to access extra starch somehow (admittedly possible with corn as an adjunct.. if you hadn't performed a cereal mash)

I am taking from this that if gelatinization didn't go to plan, the polenta would stay in the mash as a solid, not dissolved in the wort.

I guess the problem is - did the polenta convert, or did I get better efficiency from the mash? h34r:

Polenta is ungelatinised corn - I personally wouldn't put it in my mash tun. Just because the people who posted here haven't had problems, doesn't mean they can't occur. Its probably fine to use, but why settle for probably?

I think I have a lot more research to do before I am willing to put the polenta in dry.

... if you use instant polenta (pre-cooked), it is fine to use. Thats what I usually use if I want to use corn.

I reckon I've seen this at the store. Great idea - might give this a go for the mild.

Flaked maize is pre-gelatinised as part of the flaking process and can be added directly to your mash tun without worrying about whether you do or don't need a cereal mash. You don't.

If it is possible to add maize dry, I guess the only reason you would need flaked maize is when you are doing a kits and bits and using spec grain with no diastatic power... yeah?


Cheers for the reply.

 

[Thirsty Boy]

no - gelatinisation isn't conversion. Gelatinisation happens, then conversion. Corn needs to be mashed every time no matter what.

Conversion occurred in your brew - why on earth wouldn't it??

 

[jonocarroll]

no - gelatinisation isn't conversion. Gelatinisation happens, then conversion. Corn needs to be mashed every time no matter what.

Conversion occurred in your brew - why on earth wouldn't it??

Okay, perhaps I've been a little reckless with my meaning. I do understand the above (my comment on k&b aside).

When I said "did the polenta convert?" I meant that as a proxy for the gelatinisation - it wouldn't (necessarily) convert without the gelatinisation, yeah?

After a little more research, BribieG's answer seems to fit the bill for my original question- gelatinization will render the starches soluble in water. If the polenta (or in his case, rice) 'disappears', then gelatinization occurred, and conversion will surely follow. For very finely ground polenta, the gelatinization may not be necessary at all, and the enzymes could attack the free starches, but I would imagine that rice would be an entirely different matter altogether. I used coarse polenta (no good reason), and next time I will give the cooked polenta a try.

Cheers for the replies all.

 

[Screwtop]

Polenta is ungelatinised corn - I personally wouldn't put it in my mash tun. Just because the people who posted here haven't had problems, doesn't mean they can't occur. Its probably fine to use, but why settle for probably? ... if you use instant polenta (pre-cooked), it is fine to use. Thats what I usually use if I want to use corn. Or do the cereal mash.

Flaked maize is pre-gelatinised as part of the flaking process and can be added directly to your mash tun without worrying about whether you do or don't need a cereal mash. You don't.

TB, it WAS my understanding that corn grits or cracked corn as we call it is ungelatinised corn and that polenta is gelatinised, and that was why polenta only requires heating basically (10 min) in water to soluabilise the starches.

QB adding this corn starch (cooked polents porrige) to the mash (have always wondered why adding cornstarch wouldn't be easier) where enzymes are available for conversion would then mean that your gravity would match estimated gravity if a potential for the corn adjunct was included in the malt bill. The conversion of the starches will produce sugars, the fermentability should be high due to a high percentage of glucose from conversion of the corn starch. This is why adding corn thins body, it's a corny way of adding sugar :lol:

Screwy

 

[Fourstar]

Won't the amylase enzymes in your saliva convert the starches anyway? Isn't this why a chewed grain still tastes sweet? Is your wort perhaps just less malty, and therefore the sweetness is more pronounced?

I'd probably say the increased sweetness is due to the enzymes converting the starches in the corn exclusivly to Maltose (ThirstyBoy could probably chime in/correct on this.)

Polenta is ungelatinised corn - I personally wouldn't put it in my mash tun. Just because the people who posted here haven't had problems, doesn't mean they can't occur. Its probably fine to use, but why settle for probably? ... if you use instant polenta (pre-cooked), it is fine to use. Thats what I usually use if I want to use corn. Or do the cereal mash.
Flaked maize is pre-gelatinised as part of the flaking process and can be added directly to your mash tun without worrying about whether you do or don't need a cereal mash. You don't.

You can put raw polenta into your mash tun directly and it will gelatinise and will convert. Treat it like raw barley or wheat, it will gelatinise at A & B Amylase temperatures and to be safe i would probabaly extend my mash to 90 mins to ensure complete conversion. As an example raw wheat nees to gelatinise and i dont see many people doing a cereal mash to achieve gelatinisation when making witbiers? Saying that, i wouldn't add a high % of raw polenta directly to the mash tun purely due to the coarseness of it compared to barley or wheat.

In this instance i would pregelatinise by holding it at gelatinisation temperatures or in extreme cases go the route of a cereal mash. Whenever i have used polenta it has been the only adjunct which a crapload of high diastatic malt (pils generally) so conversion post gelatinisation hasnt been an issue for me. Maybe fi you where using a low diastatic basemalt you might have conversion issues post gelatinisation.

TB, it WAS my understanding that corn grits or cracked corn as we call it is ungelatinised corn and that polenta is gelatinised, and that was why polenta only requires heating basically (10 min) in water to soluabilise the starches.

Raw Polenta is just highly milled maize/corn. Instant Polenta is pre-cooked/steamed therefore gelatinised. Also the reason why it comes together and is soft so quickly.

 

[Thirsty Boy]

You can put raw polenta into your mash tun directly and it will gelatinise and will convert. Treat it like raw barley or wheat, it will gelatinise at A & B Amylase temperatures and to be safe i would probabaly extend my mash to 90 mins to ensure complete conversion. As an example raw wheat nees to gelatinise and i dont see many people doing a cereal mash to achieve gelatinisation when making witbiers? Saying that, i wouldn't add a high % of raw polenta directly to the mash tun purely due to the coarseness of it compared to barley or wheat.
----
Raw Polenta is just highly milled maize/corn. Instant Polenta is pre-cooked/steamed therefore gelatinised. Also the reason why it comes together and is soft so quickly.

You are correct, polenta is just corn, the starches in corn gelatinise at higher tempertures than in raw barley or raw wheat, or the malted versions of either.

Polenta (uncooked) will probably, mostly, gelatinise at normal mash temperatures, not just plain will. And your mash schedule will make a difference to whether it ends up changing your fermentation profile or not too. Different info sources quote maize gelatinization temperatures at between 60 & 80C ... all cool if your batch is full of starches that gelatinise at 60... but if its 74-80 (which is what most of the texts say) then its only going to partially gelatinise in a normal mash.

The example of raw wheat is a bad one - raw wheat starch does (mostly) gelatinise at mash temperatures

Its my understanding that corn starch hydrolises into roughly the same proportions of glucose, maltose, etc etc as does malted barley, ie mostly maltose ... but it could be rice I'm thinking of. Its one or the other. If people are sure their corn mashes taste sweeter than barley mashes - it probably is corn that gives a higher percentage of glucose though. Glucose is considerably sweeter than maltose.

Uncooked Maize in the form of corn grits, corn flour, polenta ... should be pre-cooked and the best way to do that is with a cereal mash routine. You might be able to get away without it.. but you also might not. There are options to avoid a cereal mash - flaked, torrified or micronised corn (popcorn basically) and pre-cooked or instant polenta.. so there isn't even any need to bother with "might".. why would you when you can have "already done"??

But if normal polenta is working for you -- I ain't telling you to stop or that you're wrong. Its just that I wouldn't use it myself.

 

[jonocarroll]

You are correct, polenta is just corn, the starches in corn gelatinise at higher tempertures than in raw barley or raw wheat, or the malted versions of either.

Polenta (uncooked) will probably, mostly, gelatinise at normal mash temperatures, not just plain will. And your mash schedule will make a difference to whether it ends up changing your fermentation profile or not too. Different info sources quote maize gelatinization temperatures at between 60 & 80C ... all cool if your batch is full of starches that gelatinise at 60... but if its 74-80 (which is what most of the texts say) then its only going to partially gelatinise in a normal mash.

The example of raw wheat is a bad one - raw wheat starch does (mostly) gelatinise at mash temperatures

Awesome post. Cheers!

pre-cooked or instant polenta..

Buying some tonight, will add it to the mash on the weekend. Would you recommend heating it up to the mash temp in some water to prevent heat-loss?