Convert Starch to Sugar Problem? Potatoes

[snowwake8]

I took 20 lbs. of potatoes and boiled them for one hour. Then I drained the water and mashed the potatoes. Then I added 6 gallons of water and brought the temperature to 150 degrees F. I then added 2 lbs. of crushed 6 row malt and kept the temperature between 150-160 for 2 hours and 15 minutes stirring every 15 minutes. I then let cool to 85 degrees over night. In the morning I strained into my carboy. I pitched wine yeast (put in luke warm water with some sugar for 5 minutes) then threw it in the carboy and mixed it very well. I barely got any action at all through my airlock (maybe 1 bubble every 5 minutes if that) and after 5 days I decided to pitch some more yeast. It's now been 2 more days and from looking at my airlock it still looks like there hasn't been any fermentation. I don't know what I could have done wrong to not convert the potato starch to sugars. Any ideas or help would be great.

 

[WiseEyes]

Potato wine huh. Buy some amylase enzyme form a home brewstore. Throw it in the mash it will help your conversion.

 

[triskelion]

where I'm from, pretty much every farmer distills their own poitin. sounds like that's what you're up to. lol

 

[motorneuron]

Haha, I really like this idea, but you maybe didn't have enough enzymes for all that starch. A rule of thumb is that 6-row can convert itself plus 60% of its weight in adjuncts. I have no idea how that translates from grains (which are pretty dry, like 5% moisture) to potatoes (which are like 80% water), though some crude math suggests that 20 pounds of potatoes @ 15% starch means something like 3 lbs of starch; that's the equivalent of about 6 lbs of dry instant oats (55% starch). So that sounds like not enough 6-row for enzymes, even assuming all the starches are gelatinized and therefore ready for enzymes to work. You'd need maybe more like 5 pounds of 6-row. Or, as suggested above, you could just buy some amylase. Interestingly, sweet potatoes do contain beta amylase (I think), and on the gluten-free forum there's been some discussion about mashing them alone, though no results that I know of. Plantains also have amylase, I think, and I think bananas--the process of their ripening is partly starch being turned into sugar.

The other thing is that when you boil the potatoes, the water definitely leeches out some starch, so dumping that water meant lost fermentables. I have no idea how much, though.

 

[GuldTuborg]

2lbs of malt to 20lbs of boiled potatoes? Sounds like not much conversion happened. I doubt there's much for wine yeasts to eat in there. You could try more enzyme additions, as suggested. I'm not sure what else would work.

Did you boil the potatoes whole, or cut? If cut, you probably lost a whole lot of starch when you drained the water, too.

 

[amandabab]

scrap the batch.

next batch:
boil the 20lbs potatos and reverse the cereal procedure.
boil them, mash (physically) them IN the water don't dump it.
when its cooled to 160-170 add in 4-5lb 6-row. this will start the conversion and the small amount of sugar conversion will keep it from turning to concrete as it cools. let it cool until the enzymes stop working on the cold end.

add a lb of rice hulls to the mash tun then line the mash tun with a biab bag.
add the cereal mash and another 4-5 lbs 6-row to the bag and add strike water.

vourlouf/recirculate this right after strike and then every 15/20 minutes or so for an hour adding heat as necassary lifting the bag when it sticks. even with the bag and rice hulls if you wait until the end you'll have a lot of starch/potato concrete sinking and clogging.

you'e going to ferment this monster with an ale yeast capable of eating maltose, then sir up the cake add o2 and switch to a killer like 1116 to finish it over a month or so then start racking it when ever there is a 1/4 of sediment for however long it takes to go clear and stop dropping sediment..