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How to salvage a batch with unconverted starch

capo

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I am new to all grain brewing. I did a smash beer for my first AG brew. I noticed that my 1.048 brew worked quickly then stopped at 1.015, going no further. The batch is extremely cloudy. I discovered that my mash temperature probe was reading several degrees low, and likely mashed at too high a temperature. My suspicion is that I have a lot of unconverted starch. Can my batch be saved?

I was thinking of using finings to try to clear it, and possibly pitch some more yeast (is this required?) during bottling to carbonate it. Will this work, or has anyone a better idea to save this batch? Should I just put this one under "lessons learned" and toss it?

Thanks for any replies.
 
I would not dump it. 1.015 is not that bad. mine go down to .008 but I'm not sure if 1.015 would be bad at all. as a mater of fact I have been thinking of trying to mash at a higher temp to do just what you have done.
how long has it been fermenting? what yeast did you use? what's the temps during fermentation? with this info we can better help. 
 
I have to admit, I do not know if the cloudy issues is because of the mash. I know that I get cloudy beer only when using wheat. after 4 weeks I would not think the yeast are making it cloudy.
As for checking if there is enough yeast for bottle conditioning,  what I have done before is to take a sample, about 2 or 3 oz.'s and put it in the fridge for 8 hr.'s  . then if there is yeast on the bottom of the sample it should be ok the bottle condition. well I hope someone else can tell us about the cloudy issues, and if it is from high mash temps.     
 
If it tastes worth drinking, then package/carb and enjoy it. 
 
When I say cloudy, I mean totally opaque, like a coffee with cream. I haven't tasted it but I guess that's the real litmus test. It doesn't look real enticing like that.
 
When I first started all grain brewing one of my rye beers was extremely cloudy (to much hot break getting to the fermenter) but was a really good tasting beer.
 
Capo, What you're describing is too vague for specific answers.

What do you mean by "several degrees" low for your thermometer? Three is probably not that bad but 8 might be.

What kind of beer did you make? SMaSH mean one malt, but which one?

Was 1.048 within range of your intended gravity?

What yeast did you use? You have 70% attenuation, now and maybe the yeast isn't done.

What temperature is this beer being stored at?

How did you oxygenate the beer?

Assuming good sanitation and healthy yeast, there's a wide range of reasons for cloudy beer. Starch haze isn't usually milky. In fact, you'd have seen that kind of haze even before you added yeast. If the beer tastes and smells like beer, but also a little like raw bread dough, then I would tend to think yeast is the cause of the haze.

Once the gravity is the same for three days, you can add Polyclar (pvpp), biofine or gelatin to help the yeast flocculate.
 
I thought I had posted the details, but for some reason aren't here. Smash is Maris Otter with IPA levels of Cascade hops. Yeast was Wyeast 1217 west coast ale, no starter, ambient temps around 18C (64F), internal temp 22 (71). Mash goal was 154F, thermometer was off by about 6F, so I suspect mash was around 160F. SG near goal. Possible I didn't Vorloff enough, first AG batch. Two AG and and two extract batches since, no issue. Primary 2 weeks, secondary 2 weeks. Still milky, smells ok.  This is the only milky batch I've produced in 15 batches. Brew went strong initially, then just appeared to stop dead.
 
Oxygenation was done by pouring from the kettle tap through a screen strainer at the top of the fermentor which causes lots of splashing. Has always been sufficient in other batches.
 
I'm hoping that the final gravity has not dropped for at least three days.  If so, then we can go to the next stage.

So, the only process fault was an unintentionally high mash temperature. That's great, because it can explain the low flocculation from two vectors.

Flocculation is both Calcium and sugar dependent. The attraction that creates flocculation is enhanced with calcium, but inhibited by sugar/carbohydrate presence. We shorthand this relationship by advising proper calcium content and waiting for full attenuation.

The yeast strain you have is noted as a "good" flocculator, meaning it clears >80% once the beer is fully attenuated. I suspect that it also is used to the relatively higher Calcium levels of West Coast water, too.

Basically, the additional dextrin and polysaccharide content of the beer, and perhaps low calcium are at fault, here. Fix one or the other and you would probably have had a normal fermentation.

It appears that finings are definitely in order. Polyclar has the strongest electrical charge for pulling out yeast. It has the side benefit of removing tannins, too. However, my preference would be Biofine Clear. This is a non animal clarifying agent (other Biofine products have isinglass, if that's important to you). 

This is one of the few times I'll suggest a secondary, too. The clear surface area will help the yeast flocculate.  Once racked and fined (sounds torturously medieval, right?), you should crash chill it, if at all possible.

If you're bottling and using priming sugar, I would suggest using gelatin at that time, to help pull yeast clear after carbonation. Otherwise, you may have powdery sediment.
 
Excellent explanation and advice. Calcium is definitely not the issue with my water. Suspended yeast and unfermentables are definitely the issue. I am just about to receive a new fridge for my brew area. I may try cold crashing while I try to get some finings, I never thought to try that.
 
Follow up. I cold crashed the fermentor, then brought it back out into the normal temperatures. Og did drop after that, and finished about 1.011. Bottled it last week, and saw all kinds of white stuff that stuck to sides of the carboy. My guess is that it was unconverted starch. Tried beer today after only one week. Still hazy but actually pretty tasty and not as sweet as I expected. I think with some time will end up to be a decent beer, as it looks like all the excess starch precipitated out or stuck to the glass.
 
The stuff on the carboy is yeast and possible some protein not starch.

I mash >160 pretty regularly for small beers and do not have any problem with conversion.  alpha amylase is still plenty active, very active indeed, up at that temp so conversion was happening. The sugar chains being formed were still quite long but not starch long, still sugar.

I suspect it just wasn't done. you say it dropped another 4 points so I suspect when you moved it to secondary after two weeks you slowed the fermentation way down because you removed much of the yeast, and the most floculant yeast at that.

Some maltsters MO can be a little under modified so there can be some protein haze that is very difficult to shake.
 
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