How can I filter the solids out of my homemade pumpkin spice syrup?

Question

I'm a big fan of pumpkin spice lattes, and I've been experimenting with a few recipes for making my own pumpkin spice sauce at home. It's pretty simple; simmer equal parts sugar and water with varying amounts of pumpkin puree, nutmeg, cinnamon, cloves, allspice, ginger, etc. for about 20 minutes or so. The problem is that none of these spices are soluble in water, and I can't seem to strain out the solids enough to where it won't make my coffee "gritty."

I've tried filtering the mixture through a metal sieve used for cold brew, but the grains are much smaller than ground coffee, so it (mostly) passes through the pores. I tried cheesecloth, but it clogs up quickly and turns into a mess. The most success I've had was pouring the mixture through paper coffee filters straight from the stove while it was still boiling hot, but this has a few issues:

1. The mixture forms a "skin" at the bottom of the coffee filter and the flow slows to a few drips at a time as it cools.
2. To hurry things along, I wind up going back and forth between two containers using a clean coffee filter each time, but I wind up wasting a ton of filters this way.
3. Doing it like this takes hours and it still laves a gritty, sludgy mouthfeel in my coffee.

Honestly, this process is making me feel quite stupid. What do I do?

Answer 1

Straining

Use cheesecloth.

You don't describe your process with cheesecloth in much detail, but I would suggest

1. line a colander with a couple of layers of cheesecloth, and place that colander over a bowl to collect your pumpkin spice syrup;

2. pour the mixture of spices, simple syrup, and pumpkin puree through the cheesecloth;

3. let this stand for five or ten minutes;

4. (this is the step you seem to be missing) gather up the cheesecloth into something that resembles a bindle, and squeeze; you should be able to get a good amount of the remaining syrup out of this mass.

As an optional final step, run the resulting syrup through a coffee filter.

Whole Spices

You don't describe the state of the spices that you are using, but it sounds like you might be using ground spices. If so, and especially if you are using pre-ground spices from the grocery, I would suggest not doing this. Use whole (or slightly broken up) cinnamon sticks, use whole (or gently crushed) cloves and allspice, and use (maybe) diced crystalized ginger.

You will likely have to steep these things a bit longer, but the advantage is that the spices will be large enough to mostly strain out with a strainer, and should not clog up a coffee filter or cheesecloth.

Recipe

It might also be worth noting that the "traditional" pumpkin spice latte is made with a pumpkin spice syrup, which contains the flavors of spices which one would use in a pumpkin pie (clove, ginger, cinnamon, etc), but which does not actually contain any pumpkin or pumpkin flavor. If you are looking to reproduce that latte, you might be better off making a simple syrup with those spices, and omitting the pumpkin puree entirely.

Answer 2

Using whole spices is the way to go, as they will filter out with your metal sieve. You may need to cook the mixture or steep the spices in longer if you use whole spices, you'll want to taste as you go to learn how long it needs.

If you must use ground spices I have a few suggestions:

• Use a jam bag, and suspend it above a bowl. The liquid will drip out, you can also squeeze it
• Add the sugar later: the more sugar you put into solution the more solid it will get as it cools, you could cook the spices in pure water, filter and then add the sugar afterwards
• Use a siphon: when you brew beer you end up with a lot of solids on the bottom of the fermentation vessel. One way to get the liquid out is to siphon it off into a different container. This sounds like more trouble than it's worth for your particular application, but worth noting

Answer 3

If the spices sink to the bottom of the container, it may be better to decant the mixture:

Remove the liquid on top without disturbing the sludge at the bottom.

You can attempt to ladle the liquid from the top, pour it out slowly, or use a hose to siphon it off.

I would also be worth noting that ‘pumpkin spice’ doesn’t actually include pumpkin typically. It’s just the spices. If you really want to include pumpkin flavor, you may want to infuse the spices into a syrup, then add that to the pumpkin instead of doing them both at the same time.

Answer 4

Your problem is the viscosity and the sugar does nothing but hinder the extraction process (competing solute). So just extract, filter, and then add sugar and reduce.

Answer 5

For filtering out spices, after a prefilter (with a fine metal sieve) I tend to use coffee filter papers. Ideally you'd set one up in a filter cone, but it is possible to use a funnel instead.

In you case with the pumpkin puree it's a little harder. I'd still use coffee filters, but start with one of the other suggestions: either cheesecloth or sedimentation, to get a rather cloudy liquid that will filter fairly easily

Answer 6

I've no idea if, or how well, this might work, but instead of trying to filter the spices out after simmering, you might try creating a "spice bag" out of cheesecloth (or possibly a coffee filter) so that they never really mix in in the first place. I would imagine you would either need more spices for a given quantity of liquid, and/or to simmer for longer (because the spices wouldn't circulate as much), but it might be worth a shot.

Answer 7

I've found a French Press does a really good job filtering out the spices and just leaving behind a smooth cup.

But to do that, I'm making instant coffee, drip coffee or an Americano with the steamed milk or milk on top. (Not a legit latte).