How hot to filter?

[Jonnyp390]

So here is a quick rundown of what (I think) I Know based on what others on the site are doing.

1) Filtering through a cone filter works best when the syrup is HOT. Based on what I have read as best filtering practices, most people pour off their finished (219 deg) syrup directly into their filtering setup.

2) Any heating of syrup above 190 deg will produce more niter.

So here is the question: If the syrup goes through the filter at 219, isn't the syrup sitting in the bottom of the canner above the 190 thresh-hold, thus creating more niter while waiting to bottle? Or does the niter only develop while actively HEATING the syrup back past the 190 thresh-hold?

I ask because I am trying to figure out my beautifully clear syrup I bottle a few days ago is now developing little specks evenly suspended throughout the bottle. I filter into a coffee urn and I follow what others do. Preheat the urn, allow it to go into the warming cycle, unplug and pour out all the water, give it a quick swipe with a clean towel, place my filter on top, pour in syrup, bottle as many as I can until the syrup coming out dips below 180. The syrup still left in the urn then gets poured into a pan, heated to 185, then bottled individually. My urn has a small heating element in the bottom, so on this last batch I poured a little cold water on it to quench the hot spot before pouring in my finished syrup. I was hoping that hotspot was the culprit, but the syrup is now producing the little specks a couple of days later. Any advice?

[optionguru]

Did you use a hydrometer or just a thermometer. It's possible you overcooked and are starting to get some sugar crystals.

[maple flats]

Not if you aren't adding heat or letting steam much escape. The syrup at 219 has produced the niter it will. That is then a saturation point of the minerals in it. As it cools it could hold slightly more minerals, but if you don't get it near boiling temperature you are fine.
I filter off my finisher and generally I need to add a little sap to get the right density. If it were to test light I'd boil a little longer, but that is usually not the case. Once I get the density right, I get it to 205-215 , verify density again (with an accu-cup/hydrometer) and then I draw to my mixing tank. There I mix in the filter aid and then turn on the filter press (FP). I recirculate it until well mixed, then I send it thru the FP. The filtered syrup flows back into the mixing pot until it is crystal clear, at that point I send it to a barrel or my canner. If you are using a flat or cone filter, just make sure the syrup is correct density and put it thru the filter/prefilters. Protecting it from too much cooling helps a lot. Some sort of enclosed container helps, add the syrup and put the lid on.

[The Bee]

I purchased two 2 gallon jugs with spouts, filled with cooled syrup thru cheese cloth. Let them sit for two days. Poured syrup into pan, heated back to 185 and bottled. You have to tip jug to get all the clean syrup. Pour whatever was left into smaller jar and let settle. I am very happy with outcome, for the low cost and effort involved.
Larry



Gotta figure out how to make pictures look right now ?

[psparr]

You've done your homework.

I'm leaning toward optionguru's theory. However theres a chance its niter. I filter the same way, into a coffee urn.
If its niter heres my guess. 1. Are you squeezing the filter when done to get the last bit out? That would let niter pass through.
2. Did you check the temp of the water in the holding cycle of the urn? Could be holding above 190.
3. The heating element does boil ever so slightly and I'm sure that creates a little niter. But I bottle in glass and dont have a problem with niter.

If it's sugar, some things that would help. When you dump the water just empty the best you can and don't worry about drying it. You lose water through evaporation while filtering and you might be getting heavy. Do you wet your filters before filtering? They should be damp but not dripping. Also try to cover your filter setup to keep condensation in. Hope some of this helps.

[happy thoughts]

I still use sedimentation but was reading about filtering in an old maple producer's manual yesterday and came across an alternate 2 step filtering process. They state that the bulk of niter is formed between 55-60 brix and suggest initial filtering between these densities because the low viscosity makes filtering easier. The boiling point of 55-60 brix is about 4-5*F above the boiling point of water. A second filtering will be needed after finishing but the bulk of the niter will have been removed. I think this explains why I've had pretty good luck with sedimentation as I combine partial batches of near syrup which have usually settled out over a few days time.

[Jonnyp390]

Thanks for the suggestions. I use a hydrometer and get to the right density before I pour into the urn. I am using synthetic filter with 2 prefilters. I am able to get 1 to 1.5 gallons through the filter without much fuss. I steam the filter setup over the finishing pot and I cover immediately after the syrup goes in. I have another hydrometer on order so I can check that avenue. I also think I am going to fill the urn with 190 water from the stove to preheat it rather than turning it on at all. I think the heating element might be reboiling my filtered syrup. I will report back on my next batch.