Fermentation Modifier

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Well guys I brewed a wit over a week ago which I dubbed the "half wit" because of the 50% attenuation (FG 1.020).

So I ring the HBS and the dude says sure, I've got this stuff called "fermentation modifier". I bring it home and squirt a few drops in the stuck ferment (less than the recommended dose).

Two days later I took another SG reading and it is well under 1020 (I couldn't say exactly because I was in a hurry and there was a bit of a head on the sample). Furthermore it is beginning to taste very dry. It sounds like the fermentation modifier has done its job too well - I presume by converting starches to sugar which the yeast has gladly gobbled up.

Now I don't really want my homebrewing to turn into industrial chemistry but apart from tasting a little too dry, this wit tastes good and I would like to make it a little sweeter.

So what unfermentable sugars (preferrably not artificial style) can I throw in the cut back on the dryness?
Hi Sosman

The usual thing used to make stouts sweet is lactose as it is a non-fermentable sugar. No idea how it would change the flavour of the wit though. You could probably add 50g to start and see what it does.

Oh dear.

Personally I hate that modifier/dry enzyme/pilsener enzyme stuff which seems to be sold under lots of names. Really does dry out a brew, and in an extract brew removes much of the malt flavour, leaving behind a slightly acrid taste to my palate. But with your dextrinous mash maybe it wont go that far and will stop at a reasonable gravity. I suspect it will end up very dry but I would be reluctant to try to sweeten it.

If you are kegging, then sweetening is easy. Kill the yeast and add some sugar/malt. If bottle conditioning, its a losing battle. The obvious answer is lactose, unfermentable sugar. But actually I hate that stuff as well. Its expensive (at least from a HBS) and what they dont tell you when you buy it is that despite being a sugar, it isnt very sweet. Stick a few grains in your mouth and see. I found an article once which I have now lost which compared lactose to glucose, and it is about a tenth (a third maybe?cant remember exactly) as sweet.

Anyway I once added 1 kg of lactose to 22 l of alcoholic lemonade and it was not at all sweet.

That leaves the non-fermentable artificial sweeteners which puts you squarely on the chemical brewing path. I used Splenda in another lemonade, certainly worked sweetness wise, didnt seem to ferment, didnt add a really nasty aftertaste but there certainly was a chemically taste there.

Another option is to add the sweetening agent to the glass when drinking. That was the final solution for the lemonade.

All those experiments were in lemonades with not much body and flavour to hide aftertastes, could be more successful in a (half) wit.
I guess now it's a dry wit.
If you are kegging, then sweetening is easy. Kill the yeast and add some sugar/malt

Do I kill the yeast with potassium sorbate or something like that?

I am kegging.
I'm not kegging, so I can't say from experience.

But I was interested enough in this topic to save a post from Dave now at Goliaths, in which he said 30 g of potassium sorbate in a 22 l brew would do it. I have heard of people trying to pasteurize as well. Wine makers would know best how its done.
I made the mistake ONCE of using the Dry Enzyme. The resultant brew was virtually undrinkable (IMO) and I couldn't even find anybody else to foist it on.

I don't really understand why anybody would want to add it - sure it means that the beer will have a lower carbo content, good if you're on a diet or the like but otherwise I can't see the use.

Has anybody in the group had success with it?


I really, REally, apolagise. In your original post I thought your wit was stuck at 1.020, way too high for a light, thirst quencher, WIT. All of my wits end at 1.008 - 1.012 max.

Your first all grain, I HATE MYSELF. man, what is the FG after adding the enzyme.

Did I mention to beware as this will lead to a dry beer??? I am sure I did!!! Don't add any sweeteners just keg and serve.
What is the fg, A dry beer is not bad, just VERY drinkable.
Dont feel bad Andrew, you advised the dry enzyme would infact make it dry, and i am sure sosman knew this and hence why he used well less than directions

and sosman whats this thinking of throwing it out ahhhhh never dont be a baby and just have a huge session... pity its not summer as it would be easy to drink that way :)

mine has also stopped dead on 1020, i left mine 7 days to ferment and now its Kegged cold gassed and 'm drinking my third glass, hey its high gravity but in this cold i aint struggling to drink it :) (its also not sweet so maybe this is a recepe issue not brewing?)
Thanks Ben, and your right.
Sosman don't stress, a dry beer is much easier to drink than a sweet one, As I said in the original post, this is not the easiest style to reproduce. I f your brew is drinkable then your on your way. I am sure it will be AAA.


No problemo - I take on board people's advice then make up my own mind.

It was stuck at 1.020 and I just added a few drops of the stuff. Hey its experience, I will know next time. Put it this way, it probably adds some weight to the fact that the mashing schedule wasn't right - still lots of unconverted starch in there and the yeast still healthy.

Once it is cold enough I might try adding a bit of malt to a sample and see how it tastes. I may as well continue the experiment.

And yes, dry beer is probably ok - I'm just not sure how dry this one's going to end up.

ok having a look at the style description (while having a wit myself)

Aroma: a sweet occasionally honey like character with prominent citrus, herbal and spice aroma... etc

Flavour: The flavour of unmalted wheat is typically evident. Coriander citrus etc

Body light to med.

as you can see i'm lazy and cant be buggered typing it all out but maybe a med body is ok as is Light :)
Any more witty label ideas ...

Love the label. Here's the recipe as requested. Don't be too worried about this mash scheldule, I have made this recipe with a single infusion mash @64c and it turned out great.

Sub Tropical Wit
Brew Type: All Grain Date: 17/01/2004
Style: Witbier Brewer: Andrew Clark
Batch Size: 24.00 L Assistant Brewer:
Boil Volume: 26.32 L Boil Time: 60 min
Equipment: Andrew's Mash Equipment Brewhouse Efficiency: 72.0 %

This beer tasted and smelt fantastic after4 weeks in the bottle, Fantastic summer beer

Ingredients Amount Item Type % or IBU
0.30 kg Rice Hulls (0 EBC) Adjunct 5.2 %
2.50 kg Pale Ale Malt (4 EBC) Grain 43.1 %
2.00 kg Wheat, Flaked (3 EBC) Grain 34.5 %
1.00 kg Wheat Malt, Ger (4 EBC) Grain 17.2 %
25.00 gm Saaz N.Z [8.5%] (60 min) Hops 21.3 IBU
20.00 gm Coriander Seed (Boil 5.0 min) Misc
25.00 gm Orange Peel, Bitter (Boil 5.0 min) Misc
1 Pkgs Belgian Wit II (White Labs #WLP410) [Starter 500 ml] [Cultured] Yeast-Ale

Beer Profile Estimated Original Gravity: 1.049 SG (1.042-1.055 SG) Measured Original Gravity: 1.047 SG
Estimated Final Gravity: 1.013 SG (1.008-1.012 SG) Measured Final Gravity: 1.010 SG
Estimated Color: 7 EBC (4-8 EBC) Color [Color]
Bitterness: 21.3 IBU (15.0-22.0 IBU) Alpha Acid Units: 1.2 AAU
Estimated Alcohol by Volume: 4.7 % (4.2-5.5 %) Actual Alcohol by Volume: 4.8 %
Actual Calories per 12 oz: 155 cal

Mash Profile Name: Double Infusion, Light Body Mash Tun Weight: 3.50 kg
Mash Grain Weight: 5.80 kg Mash PH: 5.4 PH
Grain Temperature: 22.2 C Sparge Temperature: 75.6 C
Sparge Water: 2.88 L Adjust Temp for Equipment: No

Name Description Step Temp Step Time
Protein Rest Add 10.89 L of water at 55.6 C 50.0 C 30 min
Saccrification Add 9.68 L of water at 86.6 C 65.6 C 30 min
Mash Out Add 9.68 L of water at 99.1 C 75.6 C 10 min

Mash Notes
Double step infusion - for light body beers requiring a protein rest. Used primarily in beers high in unmodified grains or adjuncts.
Witbeers were called that becuz they were "wit" (white) with starch. If there was any starch in your wort the enzyme would have coinverted it: it would also have chopped up any dextrines to simple sugar

I really hate that enzyme and would never put ti in my beer. However, S Nichols of Mash Paddle Comp fame is a diabetic and has to use it. He has to brew it to mximise flavor, while also ensuring the beer will be dry. He then adds the enzyme towards the end. I have tasted some of his beers and they were OK, and he won State Champion at last years State comp.

Pot Sorbate, as I understand it, does not kill the yeast, it just inhibits it from reproducing thus limiting the amount of sugar it can convert. Don't take this as gospel though. Sod Metabisulphite definitely only inhibits yeast and bacteria, it is no sanitiser

Jovial Monk
Andrew thats the recipe I based mine on, altho i ran short on wheat(torified) so i used 1.5Kg and upped the ale malt to 2.7Kg
efficency was good i did the step mash, but for some reason ended up at 1020 also :( i wonder why

Ive done this recipe several times and have always ended around 1.010. What type of yeast did you use? Did you aerate the wort REALLY well.

I can't think of any reason why your batch would stop at 1.020 except that perhaps your sacchrification rest was too hot, or that the yeast just pooped out.

I use a liquid yeast starter of 1 - 1.5 ltr of very actively fermenting slurry and I really wisk the crap out of the wort prior to pitching.

I was going to ask the same question as Ben (we split the ingredients for our batch). I whipped the crap out of my wort. I figure the yeast wasn't pooped out given it kicked in again after adding in the enzyme (that's just wild arse speculation actually).

Yeast was WYeast 3944, Belgian Witbier.

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