slow corn/sugar fermentation

[danmiz]

hi all,
im on day 9 of a fermentation and was wondering if its taking longer than usual. i used..

7 lbs flaked maize
13 lbs sugar
1 packet of whisky yeast with ag

the sg was 1090 and its at 1070 now and is bubbling out the airlock about 1 bubble about every 5 seconds. im used to using turbo yeast so thats probably the reason i think it should be done already. how long should a fermentation take with what i used? btw the temp in my aptartment is not to cold.

thanks!

[Almanac]

"7 lbs flaked maize
13 lbs sugar
1 packet of whisky yeast with ag"

What is the volume of the wash and why did you add the Flaked Maize?

AM

[danmiz]

It's a 25 l wash and I added flake maize to try and add corn flavor. I brought it up to strike temp for maize and let it cool to 85 f before I pitched yeast.
Thanks

[Almanac]

Adding flaked maize adds starch which needs Alpha Amylase to convert it so fermentable sugar. The Amyloglucosidase (AG) in the Whiskey Yeast won't do the job as it onlt breaks down some starches that the Alpha can't handle.

The amount of starch introduced by the flaked maize may be interfering with the yeast and has probably sent the pH completely wrong for the wash to ferment properly.

If you do want to use maize throw in a pound of malted barley as well. That will convert all the starch and you'll get some corn flavour too. Even at this stage you should be able to get some liquid Amylase from a HBS that might do the trick.

AM

[danmiz]

Thank you. Another lesson learned from you. I appreciate it

[Capt-Cudellez]

That yeast I believe is for using on all grain washes, sounds more like a nutrient issue to me. Your basically doing a sugar wash with a some grain that wont really do much without the enzymes to convert it (as Aidan said).

When I did grain flavoured sugar washes I found giving it a good hard boil for 60-90 minutes got the best flavour - no chance of converting anything after than, but your letting the sugar provide the alcohol, so no worries there, but you need the nuits for the yeasties
I would also consider cutting the sugar to 11lbs and use unrefined over the white granulated. That gave me the best results.

I only did 5 or 6 runs of these, so far form an expert, but did a little playing about, but your mileage may differ

[danmiz]

thanks for reply! i did add 3 tabs of beano the second day of ferment if that helps. the g went from 1070 yesterday to 1060 today so hopefully i can run it and not have to toss it. not sure if i can get my hands on liquid amylase in the next day or too so should i just like it work and try and run it will it stops bubbling?

[Capt-Cudellez]

My alpha enzymes only work between 152-158F - so need to be added before cooling to pitching temp, which is the same for adding the malt.

[danmiz]

I Understand. Thx

[danmiz]

well ill see where it is in 2 days and then probably just run the wash and see what happens and chalk it up to experience.

[danmiz]

It's still fermenting at about 1 bubble every 5 seconds and sg is not down to 1040. Thus us the 14th day. Any danger on corn going bad in there? It smells fine and doesn't look bad at all.

[chill]

The corn should be fine, but it sounds like the ph may have dropped too low, the nutrients nearly exhausted, or the alcohol level is overpowering your yeast.

ph too low? Try adding a tablespoon or so of baking soda (it will foam like mad)
nutrients nearly exhausted? need to add some
alcohol level is overpowering your yeast? dilute some of the wash and see if it starts fermenting faster

Chuck

[Capt-Cudellez]

It's still fermenting at about 1 bubble every 5 seconds and sg is not down to 1040. Thus us the 14th day. Any danger on corn going bad in there? It smells fine and doesn't look bad at all.

1.040 is still very sweet, if you run it you might get some scorching or it could be fine. The mash is probably about 6%, could still get an infection at that, but I have recently intentionally soured corn using natural bacteria, and it was white with laco infection after 4 days, but once the yeast took hold it completely destroyed it.

at 1.040 I'd be tempted to try adding a little nutrient + b-vit to get it down a bit, or splitting the wash in 2 adding more sugar and repitching.
pH might be an issue, sometimes cereals really acidify the wash, but since you were using the malt yeast, I would think it should be okay with the low pH - but that's just a guess - after souring the corn was about 4pH I dint adjust and a standard ale yeast got it down to 1.014

[danmiz]

thanks for info guys1
STILL GOING. AT 1030 TODAY