Fermentation problem, AG molasses, ???

[sailor1]

I recently tried a new molasses for a rum ferment called Mother Earth Sugar Load Heavy Brix Molasses https://www.amazon.com/Mother-Earth-Sug ... B01JAMQCS2. It is designed for use somehow in hydroponics. Ingredients seem to be simple, just molasses and water. However, I had trouble getting it to ferment. i mixed a 2.5 gallon jug with 10 gallons of water, added 5 lbs of brown sugar per my usual recipe and pitched my bakers yeast and....nothing. Well, actually I tested initial specific gravity (1.200) but decided that it was probably elevated because of all of the unfermentable solids in the molasses--as an agricultural product it probably contained a lot of impurities like ash. And it checked pH and found it to be very low 3.5...but I figured the bakers yeast would still tackle it, but no luck. After a few days with no action I diluted a bit of the mash and pitched new yeast--it took off. So I diluted the main wash and pitched new yeast in proportion, but, nothing.
So...I'd appreciate any ideas on the molasses, if anyone has experience with a similar product...
And suggestions about why I couldn't get the ferment going.
My suspicion is that pH was the bigger issue, so any suggestions about how to increase it would be appreciated (calcium carbonate?)
10 gallons of unfermented wash down the toilet...I wonder what the sewage treatment plant thought of that

[Saltbush Bill]

What Temperature were you fermenting at , How did you know that it wasn't fermenting?

[Shine0n]

3.5 is low, try pickling lime in a slurry to raise it. 5.5-5.8 is optimal but mid 4's should do as well.

Get the temp up to 90°f+ so the bread yeast has the sporting chance to thrive.

That molasses is wayyy too expensive imho, there are easier cheaper products that will do the job.

Look at webstaurant.com for molasses, it's cheap and anyone can make an account. I buy 6-8 5 gal pails at the time to make shipping worth it.

Yes the high og was due to the "other" stuff in the molasses, blackstrap and feed grade will have more than the "fancy" molasses but they make a fine rum.

You can use a hydrometer on a rum wash but you'll only get your fg once the ferment is finished. You'll need to take the og-fg and multiply by 131 and that will give you the abv of the wash.

I hope you didn't just toss the wash before getting some feedback but if you did...get yourself some cheaper molasses and try again.

Rum is a very simple wash to make and can make some very good rum so don't give up and keep on gettin on.

[sailor1]

For what it is worth I didn't buy that molasses through Amazon, or pay that much for it--$150 for 10 gal. shipped to me. It was clearly not fermenting...no activity in a closed 100l fusti with airlock. I started it at about 90 degrees and over the first 24 hours it cooled to about 70.
Pickling lime is a good suggestion--I think pH is the bigger issue too. I tasted the molasses and it is really tangy.
I should have looked at webstaurantstore.com--I'm in that business and buy from them all the time, Duh! Prices are way better than the local cash-and-carry restaurant supply place.
Any other suggestions are appreciated!

[Shine0n]

Take the lime and make a slurry with it and add slowly until you have the proper ph. It's a strong base and will go way up if not monitored, if possible keep the temp higher than 70. preferably above 80 and even better at 90.

Sorry the late reply but good luck

[sailor1]

If anyone is interested, I tried another ferment with this molasses yesterday. I added pickling lime as suggested by @Shineon--I tried 8 ounces for a ten gallon ferment (using 2.5 gal. of molasses, ISG of 1.090) which increased pH from 3.7 to 4.1. Added a second 8 ounces which took it from 4.1 to 4.9. So, one pound seemed to do the trick--and the airlock is bubbling away! Morale of the story, get the pH right....

[Shine0n]

Glad it worked out for you, also you can suspend a slab of marble in the ferment and it will buffer the ph and not allow it to drop quickly.
SCD has a thread which I believe he followed another members thread about the marble. He shows on scale the weight differences from start to finish and it's impressive to say the least.

The good thing about marble, shells is that it won't raise the ph, only buffer from sudden crashes.
Lime on the other hand can and will if not monitored raise alot higher than you wanted that's the reasoning behind me saying to add and check rather dumping all in and hoping for the right ph.

Look up some threads on ph buffering and such, quite a few out there, all may not give you the remedy but may show what not to do as well.

[bluefish_dist]

I find that my molasses rums have a lot less issue with ph crashing than regular sugar rums. Looking at the makeup, molasses has calcium in it. But as you found ph is critical. Usually I just try and keep it above 4.0 and they finish well.

Try webrestaurant store for molasses. Pricing is usually not too bad although shipping can be tough.